Ran them in the match. My son and I ran close to 180 rds each in 2 different extended mags, worked perfectly. Forgot to add that with 45 rds, the mags are a little hard to seat on a closed bolt. At this point I would download 1 rd if I was going to one for an in stage reload. Maybe they will loosen up a bit with use, the pmags I put them on were brand new.