Category Archives: Precision

Feddersen 10/22 Accuracy with Gemtech, CCI, Aguila, SK+

Test Ammo - Gemtech, CCI SV, SK+, AguilaI haven’t been able to find any decisive reviews of Gemtech’s 42gr .22LR subsonic ammunition. I finally picked some up under $4/box and decided to wring it through my Feddersen-barreled 10/22.

Since my last precision testing of 10/22 rifles, I have also refined a testing process capable of higher sample volumes, so I decided to compare the Gemtech to these other subsonic flavors presently abundant in my stockpile. (Of course, since Gemtech’s ammo is supposedly optimized for use with a suppressor, this test was conducted with an AAC Element II screwed to the muzzle of the 16″ Feddersen match barrel.)

Testing

One thing that has made precision testing much easier is this universal machine rest I developed: After every shot it returns the gun to the exact same position (which can be confirmed by the 32x scope on top), so it’s easy to shoot a string quickly and with zero shooter error.

I’ve also become a little more disciplined with respect to fouling the barrel: When shooting a clean barrel, or changing ammunition types on a fouled barrel, I ignore the first five shots. Different rimfire ammo uses different lubricants, and it takes some number of shots before the bore is consistently coated in the new lubricant. Five shots isn’t really adequate to fully stabilize the bore. (A good bolt action rifle will show that ten or twenty shots are required for it to settle in.) But at the level of precision one can get out of an autoloading rimfire, five shots seems “good enough.”

At 50 yards (the test distance shot here), muzzle velocity variance doesn’t really come into play. But it certainly does at 100 yards and beyond. It was easy to prop a chronograph in front of the machine rest and record the velocity of every round fired during the testing.

Analysis

Another thing that helped streamline analysis was OnTarget’s TDS software. It can’t (yet) auto-detect multiple shots on a single target, but it does auto-detect the points of aim, and it makes marking the shots and groups fast and easy.

I took advantage of the latest statistical tools available from ballisticaccuracy.com. The aggregated data and analysis are in this Excel workbook.

Summary results, here linked to TDS-marked targets, show that (in this gun) Gemtech’s ammunition is better than Aguila but worse than CCI SV:

Ammunition CEP Radius (MOA) Average fps fps Standard Deviation
SK Plus 0.37 1045fps   14.7  
CCI SV 0.50 1039fps   15.2  
Gemtech 0.58 1022fps   14.5  
Aguila 0.67 1015fps   10.0  

10/22 Precision Rematch

KIDD 10/22 in Archangel stock, Ruger 10/22 with Feddersen barrel in Vantage stock

These are both Ruger 10/22 style semi-automatic rifles built for shooting .22LR with maximum accuracy. On top is an $860 rifle built entirely by KIDD Innovative Design. The receiver and trigger are milled from aluminum, and the bolt from hardened steel. The single-stage trigger is also a crisply machined assembly that adjusts down to a pull of just 1.5 pounds. The lightweight barrel is guaranteed to group inside of half an inch at 50 yards. The gun here is screwed into a comfortable $100 ProMag Archangel Target stock

Do you have to spend $1000 to get an accurate .22 rifle? Expert barrel maker Fred Feddersen says one of his $170 barrels will turn an off-the-rack Ruger into a gun that can compete with any custom autoloader. So the second gun shown is a standard Ruger 10/22 receiver and bolt onto which I swapped Feddersen’s barrel. Of course I don’t think I can really shoot that well with a standard trigger, so to be fair I bought another $200 KIDD trigger assembly for it. The gun is shown here screwed into a beautiful $175 Tactical Solutions Vantage laminated stock.

I tested these for precision last year. This time, with a few more ammo types, I also tested all ammo both with and without a suppressor.

Testing

Both guns were cleaned and then shot through the following sequence of 40gr subsonic target loads:

  1. 30 rounds SK Plus
  2. 25 rounds SK Match
  3. 15 rounds Eley Match
  4. 40 rounds CCI SV
  5. 40 rounds Aguila SuperExtra

All rounds were fed from the same transparent Ruger 10-round box magazine. This time the KIDD ran with no hiccups whatsoever. The Feddersen-barreled Ruger, shot second, had one failure to feed with the CCI and one with the Aguila.

The raw data and calculations can be downloaded here. The targets are shown at the end of this post. Summary analysis:

Precision of KIDD vs Feddersen rifles on different ammunition
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XCR Short-barrel Precision

XCR equipped with a precision stainless 11

A precision-obsessed friend was lamenting the apparent inability of his Robinson XCR to shoot tight groups. Although it was not designed specifically for precision, I am a fan of the gun’s design. Particularly given its ease of changing barrels, I began to wonder how much we could improve on the standard chrome-lined light-contour barrels. So I sent two Lothar-Walther match-grade 1:8 rifled stainless steel blanks to Robinson and waited (seven months) for them to return as heavy-contour 11″ 5.56mm XCR barrels.

This is not a gun that is easy to shoot precisely: It is light, and its single-stage trigger breaks at over 4 pounds, which I know robs me of accuracy. In order to remove shooter dispersion from the equation I tested various configurations in a custom machine rest. I ran a range of ammunition through two standard 11″ barrels and, sure enough, 10-round groups would typically exhibit a mean radius in the vicinity of 1.5MOA. The standard 16″ light barrel, interestingly, printed 10-round groups with MR just above 1.0MOA shooting light bullets (both XM-193 and Wolf Classic!), but didn’t do as well with heavier bullets in match-grade loads (despite its 1:9 twist).

With the new precision barrels the rifle prints 10-round groups with mean radius consistently below 1.0MOA, like these:

XCR Precision 11

Note that from the short barrel 75gr .223 loads run about 2260fps. On the high end, 55gr 5.56mm clocked 2775fps.

There is some vertical stringing evident, which varies with the upper, and which suggests there is further room to tighten the design. And, as mentioned above, these groups were achieved with a machine rest. When I shoot off of bags 10-round groups open up by roughly another 0.5MOA. Suffice it to say that with a good barrel and shooter this gun is capable of respectable accuracy.

Barrett REC7 Precision

Barrett REC7 with NF-F1 and LAR

We’ve been questioning what sort of precision we can expect from a piston-driven rifle with a chrome-lined bore. Those are both features believed to reduce accuracy (vs direct-impingement and an unchromed bore). We tested our Ruger SR-556 shooting ten-round groups using the same suite of ammo as in our Savage .223 Precision test and got CEP across the board about 1 MOA (with the exception of the bottom-of-the-barrel Wolf Classic, which produced CEP of 1.5 MOA).

This weekend we got a chance to try a little harder with a Barrett REC7, a premium rifle. Shown above, we fitted it for this test with an LRA bipod and NightForce F1 scope. Five shooters took 10 shots each with two different types of ammo. Given the conditions the shooter variation was minimal. The ammo makes the difference, and this gun sets a new precision benchmark for its type:

Load CEP (MOA) 90% Confidence
Interval
Federal Gold Medal Match 77gr 0.50 (0.45, 0.57)
American Eagle XM193 0.96 (0.86, 1.13)

Savage .223 Precision

Savage 10FP in .223 Remington with Nikon Buckmaster 4.5-14x40 scope

Continuing precision testing my guns I took my old Savage 10FP to the range with boxes of six different commercially-available .223 Remington rounds. The rifle has a 24-inch 1:9 heavy barrel installed in a Choate Ultimate Varmint Stock, which makes it a superb bench gun. I mounted the 14x Nikon scope before I had found good Quick-Detach mounts, and before I had concluded 20x is my preferred minimum for precision shooting. But it’s still fine for setting a baseline with commercial ammo:

Load Avg Muzzle
Velocity
CEP (MOA) 90% Confidence
Interval
Black Hills 75gr Match 2620fps 0.23 (0.19, 0.36)
Georgia Arms 69gr Match 2705fps 0.30 (0.24, 0.46)
Wolf Gold 75gr Match 2600fps 0.59 (0.49, 0.87)
American Eagle 55gr 3170fps 0.63 (0.53, 0.93)
Silver Bear 62gr 3000fps 0.80 (0.67, 1.17)
Wolf Classic 55gr 3120fps 0.84 (0.71, 1.25)

The 100-yard target can be reviewed here.

Savage .308 Precision

Savage 10FP in .308 Winchester with Sightron SIII 8-32x56 scope

I had so much fun testing my 10/22s for precision that I decided to run analysis on my .308 Savage 10FP. This has been my benchmark medium rifle for almost a decade now, and has been abused accordingly: I have broken the bolt handle at least once and had to hammer out and even drill out stuck cases. How accurate is it now?

I shot the following two groups of Hornady 168gr OTM handloads at 100 yards. I only had 8 rounds of the first load, which uses Federal GMM cases with 44.4gr Varget. The second group is 10 shots from LC 04 cases with 44.7gr Varget. (This batch of Lake City brass has .2gr more water capacity than the Federal. The LC loads chronograph about 2850fps vs 2840fps for the FC loads. Keep in mind this is a 26″ barrel.) All loads are seated to 2.80″ and use FGM210M primers.

8-shot group 10-shot group

Based on these 18 data points the rifle with these loads has CEP = 0.30″ at 100 yards, or .28MOA. (The 90% confidence interval is .25″-.32″.) This means its 4MR is 1.3MOA — i.e., 96% of shots fired should stay within a 1.3MOA cone.

10/22 Precision Rifles

KIDD 10/22 in Archangel stock, Ruger 10/22 with Feddersen barrel in Vantage stock

These are both Ruger 10/22 style rifles built for shooting .22LR with maximum accuracy. On top is an $860 rifle built entirely by KIDD Innovative Design. The receiver and trigger are milled from aluminum, and the bolt from hardened steel. The single-stage trigger is also a crisply machined assembly that adjusts down to a pull of just 1.5 pounds. The lightweight barrel is guaranteed to group inside of half an inch at 50 yards. The gun here is screwed into a comfortable $100 ProMag Archangel Target stock

Do you have to spend $1000 to get an accurate .22 rifle? Expert barrel maker Fred Feddersen says one of his $170 barrels will turn an off-the-rack Ruger into a gun that can compete with any custom autoloader. So the second gun shown is a standard Ruger 10/22 receiver and bolt onto which I swapped Feddersen’s barrel. Of course I don’t think I can really shoot that well with a standard trigger, so to be fair I bought another $200 KIDD trigger assembly for it. The gun is shown here screwed into a beautiful $175 Tactical Solutions Vantage laminated stock.

Testing

The ammo shortage continues to plague the market for .22LR, so I consider myself lucky to still have four different types of ammo on hand. I screwed an AAC Element suppressor to each barrel, put each rifle in the Archangel stock, mounted the same high-power scope, and shot ten-round groups at 50 yards with the following subsonic 40gr loads:

  • Eley Match
  • SK+
  • CCI HP
  • Aguila SuperExtra

I have plenty of the Aguila on hand, so I used that for sighting and shot two groups with that. The Ruger/Feddersen fired all 50+ shots without any hiccups. The KIDD began to bog down at the end, experiencing a few failures to fire or extract on the Aguila. Cleaning the chamber and bolt face and testing some more showed it’s capable of running smoothly when clean, but evidently it doesn’t like too much of the copious .22LR fouling to build up. Do those tighter tolerances translate to higher precision?
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