Last night I installed the Franklin Armory BFS III in my M&P 15-22 Pistol, took it to the range, and OMG the "Kool Aid" smile I had. Thank goodness I bought several mags. The only modification I had to do is file down the lower on both sides. (there is a protrusion that blocks the binary mode). There was some minor FTF and FTE (was excepted with rimfire), I noticed when I loaded the magazine to the max (25) there was issues, So I loaded to 24 and it ran much better. I was considering running the BFS on my 10/22, but I came across a really good deal on a BFSIII for the AR, and decided to pick up the M&P 15-22 Pistol, No regrets, a little pricey, but well worth it. CCI Stingers worked the best and Federal bulk pack ran just fine. If anybody is considering building this, DO IT ! I was having so much fun I didn't record anything, but I will on my next trip (soon). Everybody thought I was running "full auto".
