I have yet to have any problems with LE ammo in the older marlins I have. My 1957 35 rem has had more than 5 boxes of LE ammo shot thru it and has never jammed on it. The '52' 30-30 has had more than one box and the 1980 Glenfield 30-30 has had more than 3 boxes. Not alot, but nary a bobble running them thru. DP