does anyone know what the head space should be on a marlin 1895 in 45-70 government? the lever keeps popping open, and i have tried the easy fixes. so i was thinking about what could cause it, and my theory is if there is to much head space, it might give the cartridge a "running start" if you will at the bolt, allowing the lever to pop. it never goes any further, but it bothers me. i know when the case swells from pressure it should be enough to keep it in place. my thinking is this happens while the case is still swelling. now that i said that, it makes me wonder if my reloading sizer die is on the small size. i can check that. along with a fired case to see if the chamber is over sized. i know the best way is cerrosafe and make a chamber casting. but money at this time of the year is always tight. and i just found out i am going to have a sizable unplanned expense paying my share of cancer surgery.