Barrel Twist and Other Wizardry

Everybody knows about barrel-twist right? The most basic feature that makes a rifle a rifle is often a very overlooked subject, and one that today we will dive into a bit more. But first, are you one of the many shooters out there who is under-twisted?

What is a Twist?

For those following the conversation that may not have a perfect understanding of the concept, lets state it clearly. Lands and grooves are the interior features of a rifle barrel, they are like threads to a screw but they run the length of the barrel. If you’ve ever looked down the bore of a rifle, you’ve seen the long twisted lines that force a bullet to rotate as it accelerates. Barrel twist is specified to dictate a bullets rate of rotation (or spinning). Much like the threads on a screw, the rifling in a barrel are cut to a specific rotational value to stabilize the bullets that will be fired down the bore. For every inch down the bore traveled by a bullet, it is rotated along its axis a certain degree, just how much depends on how aggressive the twist rate is. The twist rate is universally referred to as ONE rotation in every XX.X (numerical denomination), such as one rotation every ten inches (1-10). So if your barrel is a 1-10 (common parlance: “one-in-ten”) twist, and twenty inches long, it will have completed (in theory) two complete rotations by the time it leaves the muzzle.

So Why Are There Different Twist Rates?

The whole reason rifles are better than their ancestral muskets, is because they spin the projectile, which stabilizes It. The centrifugal spinning of the projectile gives it more stable flight, and keeps it more inline with the course it started on. Much like spinning a child’s top to keep it standing on its point, the spinning bullet keeps its point in the same direction from when it was released.

Spinning an egg to get it to stand on point is much easier than spinning a pencil, or a bottle. Mainly because of its short round shape. The longer an object is, the faster it needs to be turned in order to get it to stand on point using only its centrifugal force. The same forces are at play with airborne projectiles.

Two bullets of identical weights (115 gr), but one is obviously much longer. Take a stab at which one is the better performer…

A typical bullet fired from a 5.56 cartridge weighs 55 grains, and since the diameter of the bore cannot change, most 55 grain 5.56 bullets are similar in length. When a larger (heavier) bullet is used, it typically is longer. The diameter cant change, so the only way to make a bullet heavier is to make it longer (or use heavier materials but lets stay on topic). And longer bullets are harder to stabilize without spinning them faster. Whereas a 55 grain bullet will stabilize in an 11 or 12 twist barrel, a 77 grain bullet will not. The longer 77 grain bullet if fired from the too slow a twist barrel will tumble upon leaving the muzzle, which makes for terrible downrange predictability.

When we say fast twist, we refer to the shorter distance traveled to complete a rotation. A 1-8 twist barrel completes a rotation in 8 inches vs. a 1-12 twist takes four more inches to complete a rotation (Fast twist=Lower number and Slow twist=higher number).

The same goes for bullets of every size and weight, they must be spun at the proper rate in order to maintain stable flight.

Why Does it matter?
You might be thinking Why does this matter to me? Gun manufacturers have been making guns for long enough to know the right twist rates right? I buy ammo, load it, and pull the trigger over and over and bullets frequently hit targets if I’m lucky.

The last decade has seen great advances in bullet design and technology, vastly superior to the previous 40-50 years before it. Bullets have grown in performance, and length in many cases. Longer and pointy-er bullets have increased efficiency, making them superior performers in almost every way. These ballistically superior bullets are better at wind deflection, drop over distances, and energy retention. Additional weight and length is generally one element that these bullets share. And as we’ve already discussed, longer and heavier bullets required faster twist rates to stabilize them.

So we find ourselves in the midst of a dilemma; there are both bullets and ammunition available on the market today that require the use of faster twist barrels, and yet many firearm manufacturers still use the same barrel twists they have since the sixties and seventies.

A typical loading for the common 300WM thirty years ago would have featured a 165-180 grain bullet, either of which would be properly stabilized in the common 11-12 inch twist rate. But if you could find a box of ammunition in a store today, it could feature bullets as large as 230 grains, which require a much faster twist like a 1-8 or 1-9. If you were to shoot that ammo in your Dad’s old 300WM with a 12 twist, it would shoot like a wet pool noodle in a hurricane. Heavy loads like that will only do well with a proper twisted barrel.
Tipped bullets are another advancement in bullet technology, read more about them here

In addition to the longer and heavier bullets, there are also some bullets that aren’t heavier, but still require a faster twist than historical bullets of the same weight. For example; sticking with the 300WM, you could shoot a heavy round nosed 180-190 grain bullet from the slower 11-12 inch twist barrels, but today you can find bullets that weigh-in at the same class, but still require a faster twist barrel because they are longer by design. Monolithic copper solid bullets like the PVA Cayuga are much longer than lead cored bullets of the same weight.
The reason it matters to you as the shooter is that you must use the right combination of barrel twist and bullet if you want to do well.


Plan of Attack

To improve your performance you can approach this from two different methods depending on your plans. But before doing so, you should define your purposes (ie hunting, target shooting, long-range, etc.). If you plan to hit steel targets at a mile, then select a bullet in the caliber of your choice that will do the job adequately. If hunting moose at 500 yards is your purpose, then again choose a bullet in the caliber of your choice that will do the job adequately.

Barrel twist should be determined well before a rifle is built, click here for more tips on building your own custom rifle.

If you are building or purchasing a rifle, you can either select a model with the appropriate caliber and twist rate for your planned purpose, or you can specify that caliber and twist on your build sheet. Either way ensures that you have the proper barrel twist rate to suitably stabilize your bullet of choice.
The second method is if you already have your rifle in hand. Changing twist rates requires changing the whole barrel, so the only way to adapt is to select a bullet that best performs in the twist rate you already have. There are a surprising amount of new and better bullets that can increase your rifles performance, just make sure that you choose a bullet that fits the twist rate of your rifle.

Conclusion
Armed with the proper knowledge about bullets and twist rates, you can increase your range and performance when shooting. Some manufacturers are ahead of the curve, and already produce rifles with more aggressive twist rates. Using these barrels with appropriate twist rates to shoot the most advanced and high performing bullets available will take your shooting to the next level, and make sure you aren’t under-twisted.

-CBM

Optics: First Focal Plane vs Second Focal Plane

I may certainly be biased in my thinking, but I think that first focal plane riflescopes are perhaps the best development of the last couple decades. Sure they existed before then, but they have only become prevalent to the general shooting public over the last ten or fifteen years. Before we get too deep into the subject, lets make sure we both understand what this subject is about. So we are on the same plane so to speak.

Focal Planes
No I’m not talking about an aluminum lifting body flying through the atmosphere, I’m talking about a point of focus used in your shooting. When you look through a scope and see the magnified image of the target, you are looking through several lenses inside the scope. A first focal plane scope (often called a front focal plane) has the reticle placed effectively before the magnification. A second focal plane riflescope as you might imagine has the reticle placed after the magnification feature of the scope. These two different construction techniques allow for two differing functions. Most of us have likely used the more traditional second focal plane scope. When the magnification ring is turned and the scope zooms in or out, the reticle remains unchanged. For most of the past, with simple duplex or crosshair reticles this wasn’t a big deal as the only relevant point on the reticle was the tiny intersecting point at the middle.


As reticle technology has grown over the years, additional points (subtensions) of hold have been added to our reticles. These additional reticle markings are for measuring hits and misses as well as holding wind corrections and holdovers. This is only relevant to the discussion in that the values of these additional points can change when used in a second focal plane optic. In a first focal plane scope, the reticle is magnified with the image. As the scope zooms in, both the target and the reticle increase in perceived size. The advantage to this lens configuration is that the reticle values stay the same regardless of what magnification the scope is set to. Second focal plane reticles typically register full value when they are at their maximum magnification.

Which is Better?
Despite a revolutionary change towards front focal plane scopes, one is not necessarily better than the other. Its simply based on the user’s preference or purpose. Both types of riflescopes have their pros and cons, so better is not the way to look at it. For example, if you are shooting extreme long range (ELR) competitions then you likely would prefer the finer size of a second focal plane reticle on a target that is three-thousand yards away. And on the other hand, if you are shooting a PRS Match where you have to quickly call your own shots and make corrections at varying ranges it helps to have your subtensions uniform regardless of magnification setting. So while some folks will try to convince you that one is better, keep in mind what you plan to do with the scope.


Pros and Cons
To help you better make a choice between these two scope configurations, I’ll discuss a few of the pros and cons of either selection. First focal plane scopes as I mentioned keep the reticle values intact regardless of what magnification setting you use, this comes at an additional expense. Many manufacturers offer near identical scopes in both FFP and SFP, with the latter being the more affordable option. If reticle usage isn’t part of your routine then this may not be a justified expense. Whereas if you use reticles frequently, it is well worth the added cost.

As I mentioned above, reticle thickness can be a downside to FFP scopes depending on the reticle design. As the reticle increases in size with magnification it can obscure the target or aiming point. Second focal plane scopes don’t have this issue as the reticle is always the same size. They also don’t become so fine as to become illegible at lower power. If you have poor eyesight or other issues related to reticle size, you may be better off with a SFP scope.

If you are looking for a very high magnification optic like a 5-50X, you will find that nearly all of them are SFP, their reticles would otherwise disappear at low power, or cover up a truck at maximum power.
If you do use your reticle for measuring hits, misses, and range features with a second focal plane reticle, you may need to refresh your math skills. Using a SFP reticle to measure things at any magnification besides its calibrated setting will require you to calculate the actual value based off the magnification setting and the measurement with the reticle. Some people like math but they should not be trusted.

Conclusion
There is no wrong or right answer when it comes to focal planes, there is only an evaluation of their applications. Things such as engagement distances and moving targets should surely be considered when deciding which way to go. I have fully embraced the FFP revolution that has occurred these past years, and I think the huge increase in FFP market share tells that I am not alone. The rapid expansion of long-range shooting and related competition has likely driven the trend.

Whether you are a competitive shooter, a military or law enforcement sniper, or just a redneck hunter with serious intentions, the FFP scopes of today can give you an edge that shooters of the past would lust after. But that’s not to say SFP scopes are inferior, as the brilliant shooters of the past have shown us.

-CBM

Savage 110 6.5 Creedmoor

One of my first loves was an old savage 10FP in 308. It had all the simplicity a guy could want, and it just plain shot. I have had a bunch of Savages over the years, and I have typically had a pretty good experience with them. So when the opportunity to shoot a newer version of the model 10/110 I was eager to see how it compared to the old FP I loved so much.

My old Savage 10FP from almost twenty years ago

Savage has been around for a long time, and they have made quite a few guns in that time. One of my initial concerns with this rifle in particular was if it stood up to the classic Savages that I’ve shot over the years, I would find out soon enough.

The Model 110

The 110 action has changed through several different generations over the decades, but this current 6.5 Creedmoor model is not too different from those of the past. Like most Savage actions, is is machined from round stock with a front and rear ring. The two lug bolt rotates the floating head into the front ring of the action, and the twenty-four inch eight-twist barrel is threaded into the front of the action. The recoil lug is sandwiched there, and the whole assembly held together with a barrel nut. At the rear of the action the safety and Accu-Trigger are attached, and the whole thing is set into the polymer stock. I’ve never been a big fan of the cheap plastic stocks on economy priced rifles, but some of the few that were despicable in my eyes have been Savages such as this one. On the bottom of the polymer stock, there is a detachable box magazine that holds three cartridges.
This model is obviously marketed as a hunting rifle, it’s weight and profile features are optimized for a hunter. That being the case I wasn’t surprised by some of the features, or a lack of others. I guess you could say that in my estimation this was a basic no-frills hunting rifle.

Outfitting

Being a hunting rifle, I wanted to setup the rifle the way I would use it. The open Rocky Mountains where I hunt are full of big spaces, and shots can be had from archery range to as far as you’d dare pull a trigger. I decided to mount my Gen 1 Vortex PST 4-16, perhaps a little old school for todays market, but these older scopes always worked great for me. I actually got one of the very first ones that came out, serial number four. I mounted the scope in a pair of Warne rings, and bore-sighted it on my kitchen counter. I attached a bipod for convenience and accuracy testing, and lubed up the action before heading out to shoot.

I wanted to give the Savage a few different ammunition options to see how it performed. Some rifles are pretty picky when it comes to shooting accurately with any given ammo, so I wanted to have as many options for success as possible. The current situation at the ammo isle is pretty sad still, I have managed to find a bunch of stuff lately but the 6.5CM is still not as common as it once was. That being the case I decide to shoot a few of the factory options I had available, as well as some of my most common handloads that have done well in my other 6.5’s. Continue Reading Here…

an average five shot group from the Savage 110

Conclusion

CGS Group Hyperion K suppressor

You cant swing a dead cat in my house without hitting a good suppressor, I suppose you could say I am a bit of an addict. No it isn’t because I like to keep ATF agents employed, nor do I enjoy collecting stamps, I just love shooting suppressed. My rights were first violated over twenty years ago now, and it has only gotten worse with time, both the violation and the addiction to cans.
Today I wanted to tell you all about the latest suppressor I was able to get hands on, the CGS Group Hyperion K. I have seen them all over on social media and gun-tubers channels, but I had yet to put any ammo through one. As you might imagine I jumped at the chance.


The Hyperion
According to CGS, the Hyperion utilizes a proprietary technology to manufacture and heat treat this all grade 5 titanium suppressor. It is the product of 3D printing using the direct metal laser sintered (DMLS) process, using a laser fired into a bed of titanium powder to melt it into the pattern of their design. This alone sounds like an amazingly complicated and expensive process, but I’m just a dummy who swings hammers and gets greasy. What I can tell you, is that the result of this process has created one of the cleanest looking cans I’ve seen. The curious design and textures of this suppressor make it aesthetically pleasing and more importantly extremely light. The Hyperion senior weighs in at fifteen ounces, and this K model is even lighter at 10.5 ounces.
The back of the can is threaded 5/8-24, and also features a tapered opening to use CGS’s proprietary mounts. I would also assume that if you had a tapered muzzle to the same angle it would help there as well. The technology with which these suppressors are manufactured make them very durable according to the manufacturer, with higher ratings than expected, and increased durability rating as well. The Hyperion K has special boron nitride coating inside that helps reduce fouling inside the suppressor, and the outside has very attractive and durable DLC coating.

The Hyperion K (rear) shown next to a comparable titanium suppressor

Welcome to the Fam
I tucked the Hyperion K into my bag with a few other suppressors, and I retreated to my mountain hide. I planned on shooting the Hyperion on rifles I was already very familiar with, as well as how they react to suppressors. The first rifle and the primary one I was to introduce to the Hyperion was my Desert Tech SRS M2, the SRS is a multi-caliber precision rifle. There are untold possibilities as far as custom calibers, but at the moment I probably have over a dozen different caliber conversions for this rifle. Today on this particular range trip I had installed my 6mm GT conversion kit, which has become one of my favorites. Seeing as how the Hyperion is rated for much larger calibers, I expected it to work very well on this configuration. I have shot this same barrel with half a dozen other suppressors, so I was prepared to feel and hear something different.
Upon installing the Hyperion I did notice one little thing that concerned me. The tapered breech of the threads resulted in the threads starting approximately two to three tenths of an inch farther into the suppressor. The result obviously is that there is less thread engagement than a non-tapered thread cap. I suppose this could be a much bigger concern if you were running the suppressor on a larger rifle such as the 300RUM it is max rated for. But I felt there was enough thread engagement to be safe, so I started sending rounds.

The Hyperion K mounted on my Desert Tech SRS M2 6mm GT

The Sound
When I first broke the trigger, I was more focused on making sure the can was still there, something that comes when trying a new can on most any host. The second shot I was definitely paying more attention, and I did notice the difference from what I usually hear. The Hyperion does an excellent job at suppressing the noise, and it almost seems to have a lower tone than many of my other cans. I guess you could say its not as “hissy” as most cans, and has a bit deeper tone.
After a couple rounds I decided to start burning through some ammo, mainly because I love that damn GT and hitting things with it. The Hyperion stayed right where I’d put it, and after about twenty rounds fired over the course of a few minutes as far away as twelve-hundred yards it was definitely warm to the touch. But as titanium does, it cooled down very quickly, especially in the cold Rocky Mountain breeze.

The Hyperion K performed flawlessly, with very pleasing results on various firearms

In a very short time the can was easily handled, so I removed it and swapped it over to my Bergara BMP 6.5 Creedmoor. Certainly not a huge step up in case volume and powder charge, but it was a step up. The Hyperion sounded very nice on the twenty-four inch Bergara as well, I have shot a couple other comparable titanium suppressors on these rifles and I just like the sound the Hyperion makes a little more. It became quite apparent that would need some serious firepower in order to make this suppressor really sweat, something I wasn’t real keen to do, but I figured you guys wouldn’t be happy if I didn’t.
I would have loved to try out CGS’s vented low profile front cap, it has additional ports to allow more gas to bypass. This would have been ideal to use on a semi-auto rifle, as it would likely reduce the gas backpressure coming at the shooter.

The breech of the Hyperion K, note taper

I figured I’d so a couple good twenty round mag dumps with a 308 to get it hot, and see how the Hyperion reacts. The semi-auto rating of the Hyperion made me quite confident that nothing I was about to do was going to hurt it. After forty-rounds of 308 Winchester the can was smoking hot, so I figured one more was in order. A whole lot of heat could be seen, but the sound still sounded about the same. I have to assume it began to lose some of its effectiveness as the can got hotter and hotter, but it still was very pleasing to my ears.

Thoughts
I prefer shooting precision rifles over high volume fighting guns, so keep that in mind as I write this. The Hyperion K offers a shorter length than most full size rifle cans, and yet it seems to be quieter. I have both brake mounted and direct thread cans, I typically prefer the later so it should come as no surprise that this Hyperion fits squarely in my near perfect solution. It has lightweight, short length, and superior suppression power over most. Durability with full-auto ratings is nice to have, and I’m sure to many people that is important, but to me not so much. I am fine with the Hyperion not being full-auto rated.
The only thing about this can I didn’t like was the shorter threads, something I think I could easily overcome. I don’t like shooting big bastard magnums that often anyways, so it is of little concern. The back of the threads spun up snug and perfectly square to all my barrels.

I am mystified by the special technology they are weaving over at CGS Group, but it sure seems like they are onto something. If this Hyperion is any indicator, I think I may need to look into additional offerings to see if I’ve been missing out on anything else. I know I may be just a nobody, but the CGS Group Hyperion K is definitely worth looking at if you are in the market.

-CBM

Bergara BMP 6.5 Creedmoor

The Remington 700 rifle has been for many years a prominent stalwart in the precision rifle world. The strong aftermarket support that has accompanied the 700’s time in the sunshine has also made it a very desirable platform for custom rifle building, and the 700 footprint has been copied and cloned by many in order to take advantage of that aftermarket.
One of the many companies that has done exactly that is Bergara, and today we are talking about one of the rifles they manufacture.


The Bergara BMP 6.5 Creedmoor

The Bergara Match Precision (BMP) is a short action rifle designed and built for competition. There are all kinds of accessories and features that make a good match gun, and Bergara certainly included many of them here.
At the core of the rifle is Bergara’s B-14 two lug action, it uses a sliding front extractor and a traditional plunger ejector. The bolt nose and breech is tapered, and the assembly slides very smoothly in the action. The front of the action has a very cunning cutout to capture the recoil lug, and keep it centered. In front of that is a twenty-four inch match grade barrel made by Bergara, and threaded 5/8-24 at the muzzle. The model I tested here came with a very nice user indexable muzzle brake, which works very well to reduce recoil. The B-14 utilizes Remington 700 accessories like scope-base rails, which made mounting my scope easy.

Details: Captured recoil lug, bolt catch, trigger adjustments, chassis detail

The second half of the rifle is the BMP chassis. We live in a chassis world now, almost every manufacturer has their own version of a chassis gun. I think Bergara did pretty good with theirs, it incorporates most of the important features a shooter would want.
Built from aluminum, the BMP chassis is not particularly light at 10.4 pounds, but most match guns aren’t light so that’s fine by me. Let’s start at the butt of the chassis and move forward.
The recoil pad is made of hard rubber, and is quickly indexed by loosening a thumbscrew just in front of it. There is very rough rubber like surface between the butt-pad and the rear face of the stock, this allows the butt-pad to be easily fit to the shooter and maintain solid lockup with minimal torque. Just in front of that is the length of pull adjustment, which is easily done by loosening a wingnut on the butt-stock to adjust to your liking. Then it is easily snugged back up for a solid feel. The adjustable cheek-piece is adjusted the same way using an identical wingnut to release the cheek-piece to be adjusted to your scope height. The whole process of fitting the chassis to my taste took only a few moments and zero trips to the owners manual.

Moving forward on the chassis is the pistol-grip, the model I have came with a vertical MDT adjustable grip. Many people don’t care for the vertical grip, but they are wrong in my opinion. The precise adjustability of the MDT allows for perfect trigger finger placement and pull.
The adjustable trigger of the BMP felt perfect just the way it came, I felt no need to adjust it any lighter, even though that is what I usually do. At the front of the trigger guard is the wide magazine release for dropping free the AICS type magazines, the rifle came with the Magpul version which I quite like. The slippery polymer seems to allow smoother feeding than some metal magazines. The fit of the magazines seemed just a bit looser than I would expect, but at no time during my testing did they malfunction or fall out, so I guess they are perfectly fine.
The forearm of the chassis features MLok slots on all the right spots, which allows users to add and adjust any accessories they feel necessary. There are also steel insert flush cups to quickly install and remove your sling, there are correlating flush cups on the rear of the butt-stock as well. The top of the forearm seems to be drilled and tapped for a night vision optics bridge, which I was unfortunately unable to use.

Like a Glove
There were few things I felt needed to add to the BMP, but I did have to install one of my favorite accessories which is the Area419 ARCALock rail on the bottom of the forearm. On top of the rifle I mounted up one of my nicer scopes, deserving of a ride on the BMP was the Kahles 3-18X56. It was a perfect fit for the rifle, and after sliding on my Atlas Bipod I grabbed some ammo and headed for the hills.

Continue Reading Here…

First Round Pop – Why The First Shot Is The Loudest Using A Suppressor

The whole reason you bought a suppressor was to get rid of the noise involved with shooting right? Today we are going to discuss one of the phenomenon that comes with suppressors, and one not everybody is familiar with. First Round pop (FRP) as it is most commonly known, is the additional sound that comes when the first shot of a string is fired from a suppressed firearm. But is it something you need to worry about?

What Causes FRP?

FRP is caused by the presence of unburned oxygen in the suppressor when a shot is fired. The available oxygen inside the suppressor is ignited by the burning gasses and pressure from the muzzle. Subsequent shots are typically less volatile due to the combustion of the oxygen during the first shot. As you continue to fire cartridges, the suppressor body is filled with burnt gas from previous shots, eliminating secondary combustion inside the suppressor. Obviously, if your shots are spaced out enough, the gasses can leave the suppressor and be replaced by fresh air, allowing the cycle to start anew.

What Effects FRP?

FRP varies between suppressor type, cartridges, velocity and other variables. A larger suppressor can house more oxygen, and higher pressure cartridges can cause additional pop volume. You could also experience additional pop from using a suppressor of a larger bore than necessary, as it allows faster ventilation of the suppressor body. The size of the cartridge and the powder charge inside it can also effect the significance of FRP.

Sub-sonic vs. Supersonic

Subsonic shooting is the apex of suppressed shooting, movie-quiet suppression is the goal with sub-sonic suppressed weapons. So as you might imagine, FRP is the adversary of sub-sonic shooters. Some folks even go as far as purging their suppressor with inert gasses prior to shooting to avoid it. Other things such as suppressor wipes can also help keep oxygen from entering the suppressor body and causing FRP.

Supersonic cartridges are already quite noisy, so it is less likely as big a concern for those shooters. Personally I don’t worry too much about it, and for the most part I rarely even notice.

Living with FRP

If your like me, you probably don’t worry much about a few extra decibels when you start a shot string. But if you are one of those who like to play sniper in the back 40 with raccoons or hogs, then you may go to extremes to avoid this pesky pop. Make sure you have the best suppressor for the host you intend to shoot with, some are much better matched to your host than others. The right suppressor can produce less FRP, and if you use some of the other practices to reduce it you can get some very unsuspicious results. There are suppressor gels that you can squirt into the suppressor prior to your first shot that will aid in suppressing FRP. You could also purge your can with inert gas before heading out, and cover the muzzle to keep it inert. You could also do something as simple as adding a touch of water to the inside of your suppressor prior to shooting to help keep down the FRP. Just make sure that whatever practice you use is approved by the suppressor manufacturer, this will help you avoid costly repairs and additional wasteful NFA taxes.

Final Pop

First round pop is simply a biproduct of suppressor design, it can be a problem if you are a CIA spook or suburban hunter. But in the end it is mostly a manageable problem for some, and very minor inconvenience for others. Fuss with it if you must, and enjoy the pleasant sound of silence when it seems least likely.

-CBM

SAI Optics 1-6X24 LVPO Riflescope

The only thing I like more than rifles, is riflescopes. If I could I would probably have two or three scopes for every rifle, each of my different purposes would utilize a different optic. I often make the comparison to women’s shoe collections; this scope might go well for a sunny day and a pair of jeans, and this other scope might be better for a dimly lit walk on the cabin porch.
But to stay on topic, today I want to focus on another great little optic that scope addicts like myself will enjoy. And that scope is the SAI 1-6X24 from Armament Technology Inc. (ATI), the same people that bring you the Elcan Specter and Tangent Theta.
With a heritage like that, I expected the SAI 6 to be a home run optic for a battle rifle type sight.

The SAI 6 is a one to six low power variable optic (LVPO), the one power setting is to be used much like iron sights or a red dot sight. The six power maximum is designed to be utilized in a longer range engagement, with the rest of the power spectrum to be utilized at the shooter’s discretion as needed. The scope features a calibrated drop compensating reticle called the RAF (Rapid Aiming Feature), it is available with drop curves for both 5.56 and 7.62 ammunition. The reticle is mounted in the first focal plane of the riflescope, this allows the reticle values to stay constant regardless of magnification setting. All this is mounted inside the thirty-millimeter tube, and MRAD erector housing.
The SAI 6 has many features very similar to other LVPO riflescopes, such as an adjustable diopter on the eyepiece, and a twenty-four millimeter objective lens. But it also has some features that set it apart, such as an included anti-reflection device that threads to the front of the scope. And seeing as how Armament Technologies Inc. also owns Tenebraex scope flipcaps, they also include the highest quality flipcaps to protect the SAI 6 from getting damaged or dirty. Another very welcome add-on was the tethered scope caps, a soft rubber-like tether captures both the elevation and windage turret caps. This is very handy when zeroing the rifle, as the turret caps never leave the riflescope, avoiding loss or damage.

The SAI 6 has set parallax at one-hundred yards, which is a good compromise for up close as well as distant aiming. The left turret houses the rheostat and battery that controls the illumination settings for the illuminated reticle, with ten power settings with an off setting in between. The scope’s finish is a very tasteful shade of FDE, adding yet another shade of FDE to mismatch your already multicolored rifles.

First impressions

As I lifted the scope from its box and straight to my eye, I was floored with how clean it looked. The apparent true 1X made looking through the scope completely effortless at one power, using both eyes open there was no aberration nor forcing the eyes to focus together. With the scope zoomed in to six power, the reticle detail became much more apparent, as did everything behind it. The clarity and quality of the image in this little scope is immaculate.
At six power I looked at the reticle to evaluate its utility. Off to the left of center is a range bracket series, which allows the shooter to quickly estimate the distance to a thirty-inch target or full-size IPSC target which silhouettes a human torso and head. Below the center of the reticle there is a familiar “Christmas Tree” type drop grid with accompanying windage holds that are progressively wider as distance increases. In addition to the windage marks on the horizontal posts there is a curious “X” shape surrounding the center of the reticle, I found this design to be very handy particularly with the reticle illuminated. The X tapers to the center of the reticle and reminds me of a twentieth century space sci-fi film heads up display, like the image of young Skywalker’s X-wing being targeted by a Tie-fighter. It does so without blocking out much of the target like some of the Chevron or horseshoe reticles do.

Mounting the SAI 6
Enough about the reticle for now, it was time to get this Canadian beauty into a set of rings so I could shoot with it. I chose an ADM 30mm scope mount for this scope, as it would easily facilitate rapid movement between the several rifles I intended on shooting. With the scope plumb and torqued, I mounted it up on my Desert Tech MDRX and headed to my Rocky Mountain hide.
I bore-sighted the rifle and fired a few shots. It was then that I first removed the tethered turrets from the scope, underneath I found some very clean a solid looking adjustments.

Shooting with the SAI 6
The turrets were easily adjusted using just my fingers, and after a few corrections I was zeroed. My MDRX was chambered in 223 that day, so I set to shooting with the SAI 6 to see how the drop corrections lined up. I’m not a huge fan of calibrated reticles, inasmuch as they are only calibrated for a specific ammunition and atmosphere. That said, they can be very close in many occasions, and even if they are not one need only figure out the true value of the drop points. For example the SAI 6 has drop points for three, five, seven, and eight hundred yards. While they may not be perfect, the three-hundred might actually be two-hundred and eighty yards. And the seven hundred may not be exactly seven-hundred, but more like seven-fifty. The important part is that you figure this out using the ammunition you use most frequently, and keep the atmosphere in mind.
The drop points on the RAF reticle were very useful, and not so thick as to obscure the target area. I was able to use them for engaging targets out to six-hundred yards, and the wind hold-off’s were also very handy to counter the effects of wind downrange.

I also mounted the scope on a typical AR-15 type rifle, where I was able to repeat the process of zeroing the scope, and engaging a bunch of different targets. One thing that stood out as I shot was the outstanding view through the SAI 6. Regardless of power setting it has a beautiful image that is very useful for identifying targets and seeing hits and misses. ATI manufactures at throw lever or “cat-tail” as many call them that gives the user more purchase for quickly adjusting the magnification setting of the scope. Also while speaking of accessories, the ARD shade that came with the scope is very handy at keeping sun out of your scope, and protecting the objective lens. But like most honeycomb type ARD’s, it also robs the scope of some light, and reduces the image somewhat. This is not a big deal, but something you should know if you plan on using it.

Conclusion

The SAI 6 has an MSRP of $1290.00 which sure seems like an easier sale than its closest two competitors. I have used both the Vortex Razor 1-6 and the Sig Sauer Tango 6, and I really like both of them. But the SAI 6 comes in at a lower price and for me the reticle seals the deal.
If you are looking for an LVPO or battle rifle sight like this, you would be foolish not to look into the SAI 6. The only thing I would change if I had a wish was to make it into a 1-8, as I like to have a few more X’s in case things get far away. Or even better, if ATI is listening, how about a 34mm version 1-10x? Then I would be happy to have both of them.

-CBM

The US Optics Foundation 17X

I love a good riflescope, one of the great things about having so many guns is getting riflescopes to go with them. The challenging optics market continues to push for the perfect scope, the one that has everything. Despite their best efforts, there are just too many eyes to please which leaves consumers to pick and choose the features that they find most useful. I say most useful, but there is also an associated cost with all these features. It is not uncommon to spend two to three times the cost of a rifle on the scope that goes with it. So there is a great deal of settling for when it comes to general consumers, for example choosing scopes in the 1000-1500 dollar range with similar features to a scope that costs twice that much.
I find myself lucky to live and work in a world that can help justify some of the best equipment available. And being a bit of a scope junkie, one place I enjoy some of the finest products is on the glass that sits on my rifles. I have used many of the best brands, but today as you might have guessed from the title we are looking at my latest purchase from US Optics.

The Foundation 17X
The Foundation series of riflescopes is US Optics premier line of US made sights. I’ve had several US Optics scopes over the years, last year was my first dip into the Foundation series with my Foundation 25X. And after running that scope hard for over a year now, swapping it between multiple rifles, and packing it all over the Rocky Mountains from here to nearly Canada. It has hit the top of my list, always keeping zero, and precise adjustments have kept me always on target. I’ve used it hunting everything from antelope on the plains of Wyoming, to the dark bears of Montana’s Kootenai Forest, and the elusive elk of the Uinta Mountains.
I’ve also been running 5-25’s for some years now, and I wanted to try something different. Particularly because I rarely use them on maximum power for anything other than inspecting potential targets, so the next obvious choice for me was the Foundation 17X.

The FDN17x uses the same 34mm tube as the other Foundation scopes, and at its heart is the ER3K turret above the erector. The third generation of the EREK system allows the erector to be adjusted with a center screw to the rifles zero, without moving the turret itself from its zero. This allows full turret rotation, and it also keeps all turret movement in the up direction from its stop. Unless of course I’m lost and barmy, in which case someone will be along to correct me in a few seconds.
The objective lens on the FDN17x is a modest 50mm, slightly smaller than its bigger sibling. The windage is controlled with a capped US #1 windage knob, and it stays capped for the most part as I rarely dial any wind once I have a zero. Another standard feature of the Foundation series is the illumination, using a simple and single button to power up and select brightness settings. I can count on my fingers the times I’ve really needed illumination, but I can also tell you I never would have made those shots without it. Everybody has red illumination, so last time I ordered my FDN25X I selected green illumination. And this time around just to be different, I chose the blue illumination. I’ve yet to decide which of the three colors I like the best, but its nice to be given the choice. Other improvements of the Foundation line is a shorter throw on the magnification ring, where one-hundred-eighty degrees of rotation takes you from minimum to maximum magnification.
Another great option I added on to both of my Foundation scopes was the internal bubble level. It is cunningly placed in the eyepiece just out of the way enough that you need to look for it to see it. From the shooting position you can simply adjust the focus of your eye and see the bubble and its markings to ensure your rifle is level without ever breaking your eye from the target in the scope.

Perhaps one of my favorite options with the Foundation series is the reticle choices, and I usually choose the JVCR. It is a Christmas tree style reticle, with just enough going on to not distract my brain from doing its thing. Subtensions as small as .1 MRAD are part of the reticle, but much more prevalent are the .2 and .5 subtensions.
The JVCR like most modern reticles gives the user a superior ability to spot misses and correct for them. The FDN17X and its siblings are first focal plane scopes, which I prefer over the alternative. The reticle always reads true regardless of the magnification setting, which allows you to easily measure and correct for a miss. Whether you dial or hold for that miss depends entirely on your preference, depending on the size of the correction I will often do either. Good reticles like the JVCR allow you to do exactly that without getting so much information in front of your eye that you can’t focus, or worse yet you lose your impact in the noise around the reticle.
Before mounting the scope to an actual rifle, I ran it through a few scope tracking tests to double check turret values and repeatability.

Mounted up!
I mounted the FDN17X into one of my 34mm scope-mounts, and leveled everything up. Bubble levels aren’t perfect, but they certainly can give you a very close to level mark. I carefully torqued down the scope rings checking the internal bubble level on the scope to see that it matched the bubble on the scope-mount, and triple checked them both against another level.

adjusting the zero of the ER3K turret

Then it was time to get it mounted up on a rifle, or a series of rifles better said. This scope was likely going to be one of my switch-around scopes, jumping from one rifle to another (I go through a lot of rifles). The first rifle I mounted the scope to was a Ruger RPR 6.5 Creedmoor, a great little rifle to wring out this scope and ensure it functions properly. Using the provided tools, I adjusted the ER3K knob to zero using my bore-sighting method. And after firing a few shots to confirm, I reset the zero according to impacts. Aside from this very convenient method, there are other things to like about the ER3K turret. I love the firm stop at zero, unlike the mushy stops from cheaper scopes achieved by shims, this thing stops on a dime. The large size of the knob gives you a very precise grip, and as you turn the turret to zero it stops hard. The turret has twelve MRAD per rotation, which for most of my rifles will take them out to their usable limits.
Today I was only able to take this little Ruger out to nine-hundred and fifty-yards, plenty far for sure, but not even into the second rotation of the FDN17X. As I am accustomed, I made corrections using the JVCR reticle, and using it to measure target sizes.
The clarity and brightness of this scope is superb, watching leaves flutter on the distant ridge made wind estimating more simple. Even at nine-hundred and fifty-yards picking out the soil rolling downhill from my misses was visible, as was the occasional snow flurry floating between my target and I.

Another day brought another rifle, the FDN17X was destined to end up on one of my MDRX rifles. This one has just received the 6.5 Creedmoor conversion kit in it, with a twenty-inch barrel and the new Blk Lbl Bipod twenty-inch handguard installed. The beautiful Tungsten Cerakote of this scope didn’t exactly match the black of the rifle, but I’m okay with that.
I quickly reset the zero on the ER3K turret using the Allen wrenches, and in no time I was ready to go. The 6.5CM MDRX is not quite as accurate as the RPR was, but still plenty accurate for many purposes. In the snowy and cold desert of the Great basin, I picked out a small white rock across a long draw. It was five-hundred and fifty yards according to my rangefinder, so after consulting my drop chart for this rifle I dialed 3.7 MRAD elevation and began evaluating the cold wind. My estimates put my wind-hold right at .6 MRAD, which is real convenient to hold with the JVCR. To me there are few things more satisfying than first round hits, and watching that first round pulverize the rock into a bright dust-cloud was exactly that. I spent an entire afternoon picking out little targets at varying distances out to seven-hundred forty-five and nine-hundred yards. I find the offset two-tenths sub tensions of the JVCR very handy and quick to make sense, this is particularly handy when you shoot in wide open spaces and mountains where the wind switches direction faster than a politician.

note bubble level at bottom of scope

Am I wrong?
As I said in the beginning, its hard to make a perfect scope that fits everyone’s needs. But I’ve found that for my purposes, these Foundation scopes seem to fit me perfectly. I don’t know if that means US Optics just nailed it, or if I’m past my prime and simply content with what I’m used to. The ease of use with the ER3K elevation turret, the clear and bright clean images through the glass, and no need for an external anti-cant level make this scope very user friendly. And though I haven’t abused this one just yet other than smacking it into a few rocks, I have no doubt it will be as robust as the other USO scopes that I have abused thoroughly.

another custom Remington used with the FDN17X

This scope is already lined up to go on several other rifles, I look forward to a bright future shooting with it. The moderate magnification and size will fit perfectly into a well used portion of my gun collection, and more than likely it will see some killing come this fall.

-CBM