There is a slight variance in frames, and I have seen many that are just a'bit tight... First thing to do is take a MEC-GAR mag and see if it fits and drops free correctly.. They are a few thousands under on all dimensions and can be definitively used as a go gauge... after that, you need to dig out the old dial calipers and start checking magazine dimensions... If the mags are super clean, you can probably expect them to fit, but much use and deformity.. whether one or four, will probably cause you trouble... If you have the frame with the grips off and the hold open out.. and the mags stripped (I don't recommend!) they would drop straight through.... Anyway, this info should help you a'bit... best to you, til...lat'r...GT
