By Al Voth
Think about this: Two guns can roll off the assembly line, one after the other, and one will be accurate and next one not. It isn't until a hunter moves into the high-dollar world of custom rifles that performance becomes more predictable. And even then there are degrees of fine accuracy.
However, there are always a few things a fellow can do to wring the most accuracy out of a new .22 LR.
With all rimfire rifles, especially semi-autos, I've found it's often useful to give them a break-in period. Initially, don't worry too much about accuracy; just do a basic sighting-in and then shoot 200 rounds through the gun to get things settled down and functioning in a consistent manner. What that's done, it's time to get serious.
Cleaning Isn’t Cosmetic
Yes, you need to clean rimfires. Although they don't need as much cleaning as center-fires, they do need regular attention. I like to give them a thorough cleaning every 200 rounds or so. And if your rifle is a Ruger 10/22, I always recommend drilling a hole in the back of the receiver so that cleaning can be done from the chamber end. Brownells sells a neat little jig for doing this and all my 10/22s have this modification. In my opinion, it's something Ruger should be doing at the factory.
Finding out what ammo a rifle likes is the next chore, and this simply involves buying a little of everything that's available and shooting it all from a solid rest to see which groups the best. In order to give this test some statistical validity, be sure to use a large sample. I normally shoot one 10-shot group, or three 5-shot groups with each type of ammo. If you've never compared ammo accuracy in a rimfire before, it'll be an eye opener.
Using the most accurate ammo you've found, move on to the next step: action screw torque settings. I think this is the most overlooked trick to getting a rimfire rifle to shoot well. Rimfires seem to be especially sensitive to how tight the action screws are. I'm not sure why, but my best guess says it has something to do with their low velocity and the resultant long barrel time of the projectile. But that's just a guess. All I know for sure is that it really matters and there's no way to predict what the gun likes.
The Ruger 10/22 I've just finished setting up likes its lone action screw tightened to 40-45 inch pounds. An Anschutz 54 Sporter I own has twin action screws and prefers 20 inch-pounds on both. A CZ 452 in .22 WRM will perform best at 35 inch-pounds. I suggest starting at about 20 inch-pounds and working your way up to 45 inch-pounds. Odds are there will be one or two magic settings in there somewhere.
That's it. Nothing expensive there. When you have a new rifle, it’s fun to spend some time with it anyway. So spending that time improving its performance and getting some practice in as well is a great project. A little tweaking can cut group sizes by more than half, just like it did for this 10/22.