I gifted my son my Glock 29 10mm and he likes shooting it, but it's a little pricey to feed. I bought him a Wolf .40 conversion barrel and took it to shoot today. We used factory ammo and it would fire fine, but the next round would not feed properly or sometimes feed, but not go fully into battery. It sounds like I need to change the spring as well as the barrel. Do they make a special spring for this conversion or is there a spring for a Glock .40 that fits the model 29? Would I get it from Glock or Wolf?