I have a custom AR-15 with dedicated 22LR barrel from Green Mountain and a Spikes Tactical Ceiner kit, and have been having FTE issues. I had this issue last year, and after using the usual cleaning methods, and a chamber polisher, I finally had to take it to a local gunsmith, and he ran a chamber reamer in my chamber by hand and cleaned out the built up crud and I was back in business. When you looked in the chamber you could see a noticeable build up of crud at the top of the chamber, likely from the nose of the bullet running down the chamber wall because of the high entry angle before it levels out and fully seats, at least that is my thought. The wax and lead of the rounds rubs off and build up, and then sticks to the case after awhile.

Well after about 1000 rounds and a year later the same issue is happening again, and my local gunsmith is no longer around. So I went to Brownells and ordered a Mason 22LR Match Finish Reamer (513-050-015WB), thinking I could just do what my local guy did and have the tool to keep doing it as I continue to shoot my rifle. Got it and it doesn't fit my chamber. Let me be upfront that I am not a gunsmith, and have never used a chamber reamer before... It looks like the pilot diameter is too large to fit down my bore. The lands have a smaller ID than my chamber, and the pilot on the reamer had the same dia as the chamber, so it didn't fit.

So my question is what do I need, do I need a rougher reamer or a different kind of finish reamer? I am pretty confident I have a Match chamber and not a Sporter chamber.

Update, found a thread over at rimfire central, http://www.rimfirecentral.com/forums/showthread.php?t=276114, that talks about making a chamber scraper out of a used 223 case, which worked ok.



And another reason my gun wasnt working, the firing pin was broken. I had to modify the new firing pin which was for a Gen II Ciener Kit, and I have a Gen I.



Got it all cleaned and replaced the broken and worn parts and just need to test fire it.