Primer protrusion?

D

Dirtworks5

New member
Hello fello shooters,
I am doing some ladder testing on my new 6brx. It is built with a panda action and bartlein barrel 1-8 twist heavy varmint. I am loading varget from 33 to 34.5 gns with a 107 smk jammed .035. I have as much as .016 protrusion on the cci 450's. I am looking for some advice on what other primer to try. The loads were producing from 2990 to 3070 fps.
Thanks for any help.
Vern
 
HI Vern....are they protruding after fireing?????....or before???? how deep are your primer pokets....have you tried other primers....are these cases allready fire formed...or not.....lots of possibilities.....if they are backing out that far upon fireing you have too much headspace and/or are resizing the brass tooooo far.....you may be creating your own headspace problem, the chamber could be too deep/long so move the die up a lil...if the primer is unsupported by the ctg case/primer poket....things can burst and ruin your trigger whn the gas roars bak thru the bolt and partially re-cocks the trigger!!!!!....what does the outside edge of the primers look like ,are they still radiused like new,or blown out square and sarp,or enlarged because of all the xtra room//sorta like Abe Lincoln's hat???How much hav you shot or reloaded....are you just gettin started,,,,,you are flirting with disaster,,,Roger
 
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Roger,
The primers are protruding back into the firing pin hole in my bolt. The brass has been fireformed and fired a second time before this problem has occurred. The headspace was back .015" before firing. I have not tried any other primers yet. Any suggestions would be great.
Thanks for the help,
Vern
 
oooo.....sounds toooo hot (as Goldie Locks wuld say).....you are close to having a pierced (blanked) primer.....reduce the powder aprox 1 gr....make shure that you are not pushing (resizing)the shoulder of the ctg too far ,and proceed carefully...Roger
 
Roger,
I have not tried any lighter loads, I will try a test from 31 to 33 gns and see if i get different results. I will post any results I find, thanks for the help.
Vern
 
I am sorry I left so much literature out on my questions. I have since seen your post and the shoulder has been bumped .0015". The gun is new I just finished blowing the brass out and was trying to work up some loads for the VHA match in Wabash, IN. I have read several post from the past on 6mmbr and it seems the fellas have been using a 243 or 308 body die to size the base of the case. I had not done that, but I tried it and it solved all of my problems. It shot a .788 today at 300 at our local club with the sizing and primer problem. It seems that this case has the potential if you have the brains to drive it. Thanks for everybody's help.
Vern
 
As you suspected, 34.5 of Varget is a way hot load behind a107 SMK and a hard jam. Back it on down and find the node below. Your brass will thank you.

Greg
 
If you're getting cratering with CCI 450's that load is WAY too hot. I've read and heard that Rem 7½'s have the heaviest or hardest cups, and that might be, but I've recently blanked 6 of 49 of them with a load that showed no cratering in them in an AR (small firing pin hole, small firing pin). With WSR's and the same load primers are flatter than a pancake, but no cratering and never a blanked primer. I've found that CCI's, Winchesters, and Federal primers to be more malleable than 7½'s, but have never had a lick of trouble with 9½'s.
 
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