Elkhunter1983
Well-Known Member
What he said. The IT die is a life saver with belted mags.Check out this website
www.larrywillis.com
It will assist in dealing with the brass problems you are having
What he said. The IT die is a life saver with belted mags.Check out this website
www.larrywillis.com
It will assist in dealing with the brass problems you are having
Try Larrywillis.com he makes a collet die for belted magnums when you have this problem. Hope it helps Mike MAs you can see there is a pronounced ring just above the belt. If I adjust the die to remove it the shoulder gets bumped .005-.006. I have read that is way too much. Solutions please? I'm about ready to pull this barrel & replace it with a non belted caliber!!! Thanks. BW
http://www.larrywillis.com/I found the perfect solution from Innovative Technologies. It is a resizer that removes the ring above the belt.
Try adjusting the die per instructions. The Lee FL sizer die will bump the shoulder back to SAAMI specs so a .006 bump would be totally normal. You can't use that die to only bump the shoulder .002 consistently. If you want to only bump the shoulder .002 then get a Redding Body die which is what I use and then the Lee Collet die to size the neck to .002 tension. The neck collet die does not push/pull on the neck like an expander ball die which can cause inconsistencies in shoulder bump.OK They are Lee dies & the mark is being caused by sizing not firing. The press is a Forster Coax so I don't think it needs adjusting. Like I said if I adjust to rid the ring above the belt it pushes the shoulder back too far. I have been using Lee dies on other cartridges for 20 years & never had a problem. I also use RCBS & Forster dies in other calibers. If I need a different die I'll get one but if that does the same thing then what?
BW
Just for comparison, my Remington 7mm RM brass just ahead of the belt, fired out of a Remington factory barrel measured .514" and .513" after sized with the Redding body die.Fired brass is .516-.517. New brass is .513. Looks like oversize chamber. Had this in 6.5 CM with a Mcgowen barrel. Sent it back & they replaced it. All's well.
BW
Some 7mm Remington magnum rifles have long chambers. Since they don't head-space on the shoulder, sometimes they will stretch the brass on the first firing and expand the brass above the belt. (they head-space on the belt) Have a gunsmith check the chamber. Also have him check it just forward of the belt to see if it is possibly too wide at that point, which would allow the brass to swell excessively just in front of the belt. If that is not the problem then try a different set of dies. Also, there is a company out there that makes a die designed just to size belted magnums and remove the bulge that eventually develops in front of the belt. Most commercial dies won't remove said bulge because they won't size far enough down on the casing without bumping the shoulder back too far. I think it used to be sold by E. Arthur Brown Inc. I don't know if they still have it in their inventory. And I won't ask if you're using case lube because if you haven't stuck a case in the sizing die, you're obviously using lube. Keep your powder dry.You've certainly got a problem there but the fact that it's a 7RM is not the cause. I've reloaded a ton of 7RM and never seen that issue.
Seems like there is maybe a finish quality issue with your dies or something leaving a groove like that.