Ruger American Rimfire Accuracy

[Ricochet Rabbit]

Back in September of last year, I went out and bought a Ruger American Rimfire, and, intending on shooting an Appleseed, I mounted some Tech Sites on it. I took the new rifle and a variety of ammo to the range and did some accuracy testing. Unfortunately, my eyes just aren't what they used to be, and I was underwhelmed with the performance. Mind you, the accuracy was plenty good enough for Appleseed (I actually scored rifleman on three AQTs earlier this month, using the Tech Sites). I just expected more from the rifle. Those results are shown below:























Fast forward to today. I finally got back to the range with a scope mounted and a similar variety of ammo. The results are below:































Clearly, the rifle was capable of better accuracy than I was with the Tech Sites. In fact, I would wager that a truly good shot could have improved on what I shot with the scope. I went ahead and shot an unofficial AQT after shooting the groups, and managed a 232, even after screwing up stage 1. I'm pretty happy about the perfect score on stage four:













By the way, the scope is a Bushnell 4-12x40 with an adjustable objective and mounted on Weaver bases with Weaver Grand Slam rings (high). This scope has been great so far. So great, I bought a second one to put on my Remington 597. The views at 25 yards on 4 and 12 power are shown below:




















The table below summarizes the data:

[Matt8531]

Your groups look good; slightly better than mine shoots, which I felt was satisfactory for the price-point of the gun.

When you are computing your averages, are you compiling your shot groups to create a composite sample? For example, does your software allow you to overlay 6 groups of 5 shots to create a composite 30-shot sample? The ability to do that will play a significant role in computing hit probability statistics.

I'm not sure how much you like statistics, but here is an excellent resource if you are super-geeky, or just into that kind of thing: http://ballistipedia.com/index.php?title=Describing_Precision

[Ricochet Rabbit]

Your groups look good; slightly better than mine shoots, which I felt was satisfactory for the price-point of the gun.

When you are computing your averages, are you compiling your shot groups to create a composite sample? For example, does your software allow you to overlay 6 groups of 5 shots to create a composite 30-shot sample? The ability to do that will play a significant role in computing hit probability statistics.

I'm not sure how much you like statistics, but here is an excellent resource if you are super-geeky, or just into that kind of thing: http://ballistipedia.com/index.php?title=Describing_Precision

The averages I have here are just the average of extreme spread (group sizes added up and divided by the number of groups). The app I am using for the overlays is free, so it doesn't have a lot of festures. Thanks for the link though. I have never really enjoyed statistics, but this looks interesting. It's going to take some time to digest though. As to the rifle, I am happy with it. I just liked it from the moment I picked it up at the dealer, not really sure why, it just feels right I guess. And it shoots more than adequate for Appleseed.

[Ricochet Rabbit]

I'm not sure how much you like statistics, but here is an excellent resource if you are super-geeky, or just into that kind of thing: http://ballistipedia.com/index.php?title=Describing_Precision

So, I read over the intro page and it provides some great information. In fact, I see that the subject line of this thread is, well, inaccurate    I should have been more precise with my langauge...

I really liked this part: "Note also that precision shooters will often intentionally align their sights so that groups do not center on their aiming point so that their aiming point isn't degraded or "shot out" for subsequent shots." Many times while shooting these groups, the first shot or two knocked out the center and I was left guessing where to aim. Great article so far, thanks again for the link.

[Matt8531]

Looking over your groups, I'm curious if you've considered bullet velocity as a factor in group size. Funny things happen to bullets as they go through trans-sonic speed, that is decelerating from above the speed of sound to below the speed of sound. The result is questionable precision.

Most .22LR target/match loads are subsonic so they never encounter trans-sonic grouping issues. However, most bulk .22LR ammo is loaded to around 1250fps, which is just above the speed of sound. These projectiles, being relatively inefficient aerodynamically, will often slow into the trans-sonic velocity range (which changes with atmospheric conditions) between 25-50m, contributing to larger shot groups.

If you were to chronograph your shots (or reference the data on the carton), I would bet your best groups were subsonic and the worst groups' velocities were just above supersonic muzzle velocity.

[Ricochet Rabbit]

Looking over your groups, I'm curious if you've considered bullet velocity as a factor in group size.

Yes, I have considered velocity in my selection, as well as bullet style and cleanliness, since I also am running a semi auto. Indeed, you may have noticed that most of the ammo above is of the subsonic, target variety, with only one high velocity offering (the Mini Mags). I actually had some Federal Auto Match that I wanted to test as well, but I forgot to add it to my range bag.

Most .22LR target/match loads are subsonic so they never encounter trans-sonic grouping issues. However, most bulk .22LR ammo is loaded to around 1250fps, which is just above the speed of sound. These projectiles, being relatively inefficient aerodynamically, will often slow into the trans-sonic velocity range (which changes with atmospheric conditions) between 25-50m, contributing to larger shot groups.

The CCI Mini Mags are advertised as 1260 fps with the 36gr hollow points. I am not sure about barrel length for that number, but I doubt if I lose much out of my 22" RAR. Whether or not they go subsonic in 25 yds is a question I cannot answer at this point. However, it is, based on my results, the least accurate ammo.

I will say that the CCI's are perfectly adequate for Appleseed. And, they have other desirable features. First, they are copper washed, so I suspect they will be more reliable in my semi auto over a lengthy shoot than the target ammo (i.e., they should produce less lead fouling). Second, they were on sale and much less expensive than the target ammo.

Speaking of cost, I never had any intention of running Lapua ammo in an Appleseed. However, after testing a box of the expensive stuff, I have a better idea of what I am giving up (if anything) for the less expensive options. So, for example, Fed GM Match was on sale at a very reasonable price (alas, that sale has ended), and, based upon my results, I get performance virtually identical to the Lapua. Of course, now that I have seen how good the Eley Target is (it is my next least expensive option), I have picked up 500 rounds for the next Appleseed. So, I'll be running that in the bolt gun, and the CCI's in the semi auto.

If you were to chronograph your shots (or reference the data on the carton), I would bet your best groups were subsonic and the worst groups' velocities were just above supersonic muzzle velocity.

Alas, I do not have a chronograph, but, who knows, I may pick one up some day. It would definitely come in useful in my prep for KD. I have a 16" AR and finding velocity data can be a challenge. I would like to get an idea of trajectory before going to KD in June. I did manage to find some data for my intended load (IMI 77gr SMK) and I plugged it into the free Strelok app to come up with a starting point, but it would be nice to have data from my rifle.

[Matt8531]

Yes, I have considered velocity in my selection, as well as bullet style and cleanliness, since I also am running a semi auto. Indeed, you may have noticed that most of the ammo above is of the subsonic, target variety, with only one high velocity offering (the Mini Mags). I actually had some Federal Auto Match that I wanted to test as well, but I forgot to add it to my range bag...

Speaking of cost, I never had any intention of running Lapua ammo in an Appleseed. However, after testing a box of the expensive stuff, I have a better idea of what I am giving up (if anything) for the less expensive options. So, for example, Fed GM Match was on sale at a very reasonable price (alas, that sale has ended), and, based upon my results, I get performance virtually identical to the Lapua. Of course, now that I have seen how good the Eley Target is (it is my next least expensive option), I have picked up 500 rounds for the next Appleseed. So, I'll be running that in the bolt gun, and the CCI's in the semi auto.

Some lessons learned from my RAR and 10/22:

Federal Automatch would not cycle my 10/22 reliably; having 1-3 failures to eject per magazine. The Automatch prints ~2MOA E.S. 5rd-groups out of my RAR. No fouling issues noted. I had been using this stuff as the cheapest option at $.06/rd.

This past week, I ran a brick of Aquila Super Extra H.V. through the 10/22 with no issues at all. It also groups ~2MOA consistently. I bought the last brick at about $.08/rd, but it recently went on sale at TargetSport USA for $.05/rd., so I picked up a case for just under $250 shipped.