There may be a difference in the recoil buffer. Check on https://www.gunpartscorp.com/ to see if they can help. I hate to ask, but is it all nice and clean inside? Not too much grease pasted in there?Found a Glenfield model 60 for $50. (I like the squirrel) Won't cycle with low velocity ammo.jams with CCI minimags, New recoil spring and ejector installed...haven't purchased yet..any Suggestions ?