Hey all, so as the title suggests I am having a severe leading problem in the barrel of my M&P 22. I was about to just sell the thing but I am not one to give up on one of my guns. When I first got the gun about 6 months ago I put about 300 rounds through it on my first trip, mainly american eagle (lead nose) and winchester superX (copper plated). It performed great and when I got home I went to clean it and my bore brush got stuck in the barrel and had to be hammered out, along with the lead deposits inside of the barrel. After I realized that it was just a lead problem and that I didn't just destroy my barrel I decided it just needed to be broken in.

Fast forward to today and I cannot shoot more than 100 rounds through the thing before large clouds of black smoke exit the barrel after every shot and the lead build up is VERY apparent. I have probably around 1500 rounds through it and I am getting sick and tired of all the cleaning work I have to do after every shooting trip. I try to shoot copper plated ammo whenever I can, but 22lr ammo is very limited where I live so I don't always get to choose.

Can someone talk me out of selling the thing and putting it towards another 22 pistol? I own a Ruger mkIII 22/45 target that eats everything with great accuracy and no leading, so my M&P 22 usually gets left home because I don't want to have to deal with it. Sorry for the long post put any input would be appreciated. Thanks.

Try a couple of different brands of ammo - I have had leading problems in several different guns (including a Lothar-Walther barrel in a subgun) using Winchester 555 bulk pack. If it still happens with a clean barrel and different ammo, call S&W and have them replace the barrel under warranty.

I have tried probably 8-10 different types of ammo through it, all with the same result. Unfortunatly for me, all I have left in my stash is nasty ol' Remington Thunderbolts as I have gone through all my good ammo. I live in a small town so I have to drive 2 hours to shop for ammo, and usually my choices of 22 are none, or very limited. You might be right in calling up Smith & Wesson, I am just not expecting much as I have researched this topic on other sites and people who contacted Smith & Wesson about this problem were told that it was "normal" and to "use better ammo".

does the M&P 22 have polygonal rifling?

I believe it has conventional rifling, and I couldn't find anything in the manual that says not to fire round nose lead tipped ammunition. The lead seems to build up most in the last 1/2 - 1 inch of the barrel near the muzzle, but there are usually smaller but substantial deposits throughout. My Ruger 10/22, Henry 22 Lever action, and Ruger MkIII 22/45 all see the same ammo types as what I feed the M&P 22, but none show this ridiculous amount of leading in the barrel.

I had the same problem with a Beretta 92 conversion kit.  Got the brush stuck in the bore due to lead  build up.  I would call up Smith and Wesson and let them try to fix it first.