So I've been a long time lurker; just checking out people's gear. I finally got an AR built and picked up some gear (BFG Plateminus & D3CR) but running into some slight problems.

I got the Boonie Packer Better Mag adapter but I'm getting a lot of failures (failed to fire, extract, feed). I've only gotten a chance to use Remington Thunderbolt but my M&P 22 handgun had no problem gobbling that up.

I'm running a Taccom RF BCG, pressure plug and Taccom M4 profile barrel. Magazines are the S&W 15-22 mags. Do you think its the ammo?

Also, the bolt will close with a firm knock against the stock and sometimes when I insert the magazine. Thoughts?

Thanks in advance.

Try asking in the Rimfire AR15 section if no luck here:
http://www.ar15.com/forums/f_3/15_Rimfire_and_Pistol_Calibers.html