I have a Springfield WWll style 1911A1 (made in Brazil) that has become a dedicated host to a Marvel Unit 2 .22lr conversion. It is one of my favorite pistols to shoot and has been a great project for me to learn about 1911's. So far I have changed the main and sear springs and installed a flat housing and some wood grips. The trigger still needs work. Are there any modifications to the gun that would improve it's reliability with the Marvel conversion? It runs fairly well with certain ammo but I cannot use anything match grade and overall things could be better. I realize that many of the variables are within the Marvel unit itself (such as the recoil spring), but I thought it might be advantageous to alter some things on the host gun. Note that this pistol will never again be used to fire .45acp Therefore I am not concerned about compromising it's functionality as a "real" 1911 if I can gain some more reliability with the Marvel. One possibility would be to go with a very light mainspring, thereby reducing the resistance to the slide moving rearwards. This assumes (perhaps incorrectly) that .22lr needs less hammer impact for ignition than .45acp Anyway, I would appreciate any suggestions or thoughts about this. Thanks!