double check your crimp,if you case mouth expanded,and didn't resize the flare it will give you fits,been there done that,i had a thousand 38's that i had to re-run with a tighter crimp to remove the flare,my wife shoots them and couldnt understand at first why only some would chamber,case length plays a big part in the expanding crimping process,you may have some longer than the case you set up with,good luck,adker