Bulging Shoulder Problem

victorj19

This is my first attempt at reloading the 243 Win. but not my first attempt at reloading bottle neck cartridges. The cases were cleaned, sized, trimmed and primed. Previously, I loaded a couple of dummy rounds as I always do (no primer or powder) with some Hornady 80 gr bullets (dia .242"/6.16mm) without any issues and adjusted the die for the proper OAL.

Today my attempt to load some with Sierra 100gr bullets (.241"/6.13mm) resulted in bulged case shoulders. The die is set to the top of the shell holder in an old rock chucker. I had turned the out side of the necks. Then I tried to create another dummy round case with an unturned neck and the 100 gr bullets with the same result. The powder level is below the case neck so that doesn't seem to be the problem.

There isn't an obstruction inside the die. It was a no go trying the dummy round with the 100gr in the rifle. I tried to resize the dummy round without luck.

I would reload the 80 gr bullets but do not have the recommended powder.

What's going on here? Should I just back the die out a 1/8 turn and re-adjust the seater plug? I can pull the bullets & powder but hate the idea of losing more brass and primers.

Edit: I re-checked the trim length of the brass. Those with the turned necks measured 2.045" (used one of the cheaper Lee trimmers), those with the unturned necks were 2.035". I may have only checked the length and didn't trim them since they were already at the min. My Hornady reloading manual states a max of 2.045 and min of 2.035". The longer unloaded brass would not easily allow the bolt handle to be turned down. So, these must be trimmed some more with my manual Lyman trimmer (hope I have a pilot on hand). However, since both case lengths resulted in bulged necks, case length doesn't appear to be the issue.

Edit #2: I did find one problem I made. I used the Lee instructions for adjusting the seater die against the shell holder. I am using RCBS dies and their instructions say to leave a 1/32" gap. I have to go to work soon but will report back on another attempt.

62fuelie

On your last edit, when I use RCBS dies in my Rock Chucker I screw sizing die in until it contacts the shell holder and then lower the ram and screw it in an additional 1/4 turn. Are you getting the shoulder bulges when seating the bullet? If so, check the depth of the distance the case goes into the seating die. If the round is hitting the crimping shoulder while you are still pushing the bullet in it may be causing the bulge. Back the die off until you can run the case in without hitting the crimp point then set the bullet seating rod to put the bullet at the desired depth. If you want to crimp the bullet in place do it as a separate operation. One more step, but results is a more uniform load. The Sierra 100 grain bullets I have used do not have a crimping cannelure and one should not be forced into them.

Mobuck

You've set the seater die too close to the shell holder. Leave more gap and re-set your seating stem.
I also question your comment about a case length within the acceptable dimension "would not easily allow the bolt handle to be turned down".
It would have to be an out of spec chamber neck/throat that wouldn't allow an empty case of max trim length to chamber readily.
My experience with the 243 shows considerable variance in chamber dimensions and headspace. We have a couple of Savage rifles that are quite snug even with fresh out of the box factory loads and I have to use small base dies with one 243 to get any handload to chamber. Even with these, overall case length isn't the issue.

victorj19

Thanks guys. A gap between the die and shell holder was the problem.

Mobuck, perhaps this had something to with the long brass not chambering. I bought a used 243 barrel to replace the pitted 7mm barrel on an a Brazilian Mauser. While the gunsmith checked the head space and test fired it, the chamber might be a bit on the tighter side. Perhaps not. My reloads chamber easily now.

Jim

noylj

So, you had the seating die turned down to contact the shell holder and you were over crimping by a huge amount. Is this what happened?
For bottleneck cases, I don't flare or crimp.
I place a case in the shell holder, raise the ram up all the way, screw down the seating die body until I feel contact and screw the die body back UP 2 full turns. I place a bullet in the case, raise it up into the die, screw the seating stem down until it contacts the bullet, lower the case and bullet slightly, lower the seating stem 1 full turn, and raise the ram. This seats the bullet and with that tension on the seating stem, I lock the die body down.

victorj19

quote:Originally posted by noylj
So, you had the seating die turned down to contact the shell holder and you were over crimping by a huge amount. Is this what happened?


That's exactly what I did and the problem has been solved.