And a dirty rifle, especially if you have upgraded your barrel to a match chamber, can be a nightmare of malfunctions.
In an Appleseed last week I lent out two of our personal 10/22s to students whose rifles had hopelessly malfunctioned. These were my favorite Sporter and my wife’s iron sight 3-position rifle. Both have had Que tuneups including the chamber, bolt and crown. I normally do not lend these out because with the match chambers they can be finicky about ammo. Also, they have sentimental value. I hadn’t cleaned either after our last range outing, so they had about 100 rounds through them since the previous cleaning.
By Sunday afternoon the rifles were dirty and malfunctioning like crazy. Both had developed a hard carbon ring just ahead of the case mouth. I’m saving up for my own bore scope, but you can see good photos of the typical carbon ring here: Rimfire Research & Development.
Both rifles would fail to fire with light strikes due to the bullet failing to seat all the way leaving the case rim a little bit away from the breech face, and the bolt would not fully close which prevented the hammer from fully striking the firing pin. The firing pin would merely push the cartridge forward rather than crushing the rim. The cartridge would fail to extract about every third round by mid-afternoon. (Yes, I use upgraded extractors, too.) Each time I had to dig the cartridge out of the chamber with a knife, and could feel the resistance as the bullet was stuck in the fouling.A quick cleaning on the firing line helped much, but they still acted up some.
That Sunday night I cleaned both chambers thoroughly as described below, one with Break-Free CLP and the other with Ballistol. Yesterday I took them out for a test. Not a single malfunction in 100 rounds each.
I use solvent and a chamber brush to clean the chamber. An excellent chamber brush is the Gunsmither Tools Brush n’Mop which you can find here: Gunsmither Brush n’Mop. I also use my home-made chamber brush, made from a Dewey No-Harm brass-core brush (or similar one from Pro-Shot) bent at a 90-degree angle. You need solvent to get that carbon ring out of the chamber. A dry brush will not do the job. Spray that solvent into the chamber and let it sit for a minute or two before brushing. Also, a fast-drying solvent, such as Break-Free Powder Blast, is not as good as one that stays liquid longer. My favorite solvents are Ballistol, Hoppe’s #9, and Bore Tech Rimfire Blend. (Note that just as with the best motor oil, one can get into a really entertaining argument about which solvent is best.)
My method is this: spray solvent in the chamber and let it sit while I clean the bolt. Then with the chamber brush wet with solvent, I insert the brush, rotate it back-and-forth to scrub, and remove the brush. Then I pull a dry patch on a Patchworm from the muzzle (the plastic and cotton of a Patchworm will not harm the crown and I don’t want to push that crud all the way through the bore) and then another. Then I do the solvent/brush/patch sequence again. When the last dry patch comes out clean, I test by inserting a round with the muzzle down. In an unmodified OEM barrel, gravity should cause the case rim to fully seat against the breech, and it should be easy and smooth to remove the case by hand. If you have a match chamber, you may have to press the bullet in lightly to seat it fully, as the rifling may slightly engrave the bullet. But it should be easy to seat the case rim firmly against the breech, and easy to remove it. Finally I run a patch damp with Eezox down the bore for protection.
A factory-stock 10/22 is designed with a looser chamber to eat almost any ammo reliably even under “deferred maintenance” conditions. But if you have an aftermarket barrel or your factory barrel has been tuned up, meticulous cleanliness is the key to reliability. Normally I clean these rifles thoroughly after every 200 rounds or so. The Appleseed was a good reminder of why I do that.
Well, now it’s time to go clean these two 10/22s again.