I have a pretty new nm m1a from springfield. I hand load 185 berger hpbt for 600 yd use. I use the lee cutter and lock stud to trim cases after each reload. I ream all primer pockets. I tumble cases, then put in ultra sonic cleaner afterwards to get as clean as possible. I put a little brasso in the media, and use vinagar and water to wet clean. I put the cases in the oven at 210 degress, which is just below normal water boiling temp to dry them. I use an rcbs hand priming tool, and seat the primer below flush. I size with an rcbs full length die, but also have sb die if need be. I have an rcbs rock chucker press. I own two shell holders for 30 cal rounds, an rcbs, and a lyman. I use one shell holder on the press, and one on the priming tool. I've had a few misfires, where the firing pin strikes the primer and nothing happens. I suspect it could be the mix of shell holders not match up with the press or priming tool. The other issue I have concerns me the most. once yesterday and twice today, the action never cycled. The weapon fired, the bullet left the barrel, normal recoil, and the bolt maybe just barely moved out of batter. When that happens, I usuall have to come out of position and chop it open with my none firing hand that has the glove to get it to unlock, extract and eject. Im shooting 41.5 grains of varget. I dont think its a hold load, and I trim every case every time, even if it doesnt need it. The brass I been using is cbc once fired from a bolt gun. My biggest fear is this is an issue with the gas system not being lined up right. Ive had a fellow m14 shooter tell my my chamber could be rough, what ever that means, and ar15 shooters suggest I have a hot load.(those same shooters say "see, your primer should look like this, you can speed it up a bit" when refering to my .223 loads) I use 42.5 gr. of varget. 42.5 is about half way between safe max and safe minimum. Could the cases be getting stuck because of the mix in shell holder brands? Should I small base size instead of full lenth? If im pushing the shoulder too far back, will small base make this problem worse? This never happens with my .223 loads in my AR. I know AR's and M14's are like cats and dogs, as well as the shooters. I guess I'm a cat dog. I like my AR xtc, and my m14 at 600.