Rio jamming at end of cycle

[chickenmcnasty]

also,

It is with the winchester silver box ammo. I haven't used any reloads or tried any other manufacturer of ammo.

[Tuco Ramirez]

It sounds like the overall length of the round may be the problem. Do you have a pair of calipers to measure those rounds? I would also try another brand of ammo if you can find it. In my experience and I am not any type of expert on the matter is when the lever will not fully engage one of the first thing to look at is overall length.