I have a 4 digit MK 1 that I just recently shot for the first time. I had a few problems with it on the range. Since I feel its out of character for a 1911 type .45 to function like this heres what I've got. The slide would not hold open after all rounds were expended. I figured with the Detonics spring set up the ammo I was firing was not right for the gun. I fired PMC, American Eagle ( someone told me it's basically Gov't surplus ) and a few Federal Classic. If you agree that this may be the problem, what sort of ammo is reccomended for these. I have also heard that some magazines touted as originals are aftermarket and may cause problems. My magazine has DETONICS .45 AUTO and the loaded mag indicator that pops out of the bottom. Problem #2 the slide would not go all the way forward a few times, could this also be mag related? Any help or info would be appreciated. I enjoyed this weapon alot! Oh and any reccomendations for aftermarket mags, preferably with pinky rests would be appreciated, my little finger is bruised from the mag lip. Once again thanks for any help.

Pat