Bullet Seating Oddity

[Bradley]

I'm using an RCBS Pro 2000 to load 44 Magnum rounds. Been using this set up for years. Today something odd happened. The cast bullet loads suddenly got longer, about 0.040 inches longer. And the cases were a little buckled. They would still chamber but they were clearly buckled.

I figured out why the buckling occurred. The crimp was no longer going into the crimp grove. And this was also why the cases buckled. Lower the seating stem just a little and the problem went away. What I can not figure out is why the bullets were being seated farther out.

There was no change in brass length. The only change was the cartridge overall length.

There was no grease buildup in the die. Besides if there had been the rounds would have been shorter. I checked everything. Found nothing wrong. And the seating stem wasn't loose. It clearly hadn't moved. And this is NOT worn out brass.

So what could have possibly caused this?

[303Guy]

Well, being inquisitive, I'm waiting to hear what could have happened.

[captaint]

It could be that this happened when you were seating the boolits, not crimping. Somehow, either the boolits are bigger, or the brass opening is smaller ?? That's all I got... enjoy Mike

[44man]

Check for some wear in the press linkage. One of the pins might have wear on one side and turned on you.

[kenyerian]

Check OAL of case. Might need trimmed back to 1.285. Oops you said that the lenght had not changed. Sorry.

[edler7]

A burr or piece of foreign material under the lock ring on the die, perhaps ?

[OLPDon]

+1 on 44man. I was not familiar with the press so did a search (have included below) and found a article, half way down the page it goes into details of problems with press. Now it doesn't list your problem but most of his problems are do to wear.

Don

http://www.handloads.com/articles/default.asp?id=26

[pt4u2nv]

Not sure if it is the same situation or not but when loading cast boolits in my 357 SIG they actually crept out a few thousandths after they were seated , before the crimp. Went from .358 boolits to .357 and the problem went away.

[RobS]

I don't know what you were reloading in the past for bullets but Were the ones you seated lately a larger diameter than in the past? A fired case/unsized case can be shorter than a sized case due to the larger diameter of the brass so with that in mind a larger diameter boolit could have slightly changed the length of the brass for crimping.

As an example- The same 45 Colt Starline case:
1.265 colt overall lenth after firing from a Ruger BH before sizing
1.283 after sizing
1.276 after running it through a Lyman M-die with a .4525 spud

I have no idea if this is an issue or not but could be a possiblity.

[RobS]

Not sure if it is the same situation or not but when loading cast boolits in my 357 SIG they actually crept out a few thousandths after they were seated , before the crimp. Went from .358 boolits to .357 and the problem went away.

I've also seen this before, especially with softer bullets where the case swages down on the very bottom edge of base band. The case can acutally squeeze down hard enough to make a plain base sort of like a bevel base and in the process push the boolit up a bit in the process.

[Bradley]

Been using the same bullets and press for years. The bullets were FIRMLY held in the cases. I measured just about everything and could find nothing wrong. I check the dies. Couldn't find a problem. I'm really at a loss to explain this. The solution was simple and easy but I have no idea what was going on.

[RobS]

Bradley:

Sure is strange especially since you've been reloading the same components and using the same press and dies. I suspect that if it were the press you'd see issues when reloading other rounds as well.

[Cadillo]

I'm not familiar with the press youe are using, but having started out with RCBS dies some forty years ago, I know that some sets utilize a die that seats and crimps in one step. If you are seating and crimping in separate steps, then disregard what I am about to write.

If you are seating and crimping in one step, it's possible that that your seating stem locknut lost its purchase allowing the bullet to be seated less deeply thus causing your case mouth to be crimped into the bullet below the crimping groove. This would likely cause the case to buckle under the force of crimping as the mouth has no recess into which it can yield to crimping pressure.

Let us know what you have found out once you get it sorted out!

[44man]

I'm not familiar with the press youe are using, but having started out with RCBS dies some forty years ago, I know that some sets utilize a die that seats and crimps in one step. If you are seating and crimping in separate steps, then disregard what I am about to write.

If you are seating and crimping in one step, it's possible that that your seating stem locknut lost its purchase allowing the bullet to be seated less deeply thus causing your case mouth to be crimped into the bullet below the crimping groove. This would likely cause the case to buckle under the force of crimping as the mouth has no recess into which it can yield to crimping pressure.

Let us know what you have found out once you get it sorted out!
That is a good answer. :drinks:
Easy to just adjust the die again and relax.

[Bradley]

Separate seating and crimping dies. And the actual seating stem in REALLY tight. Could not possibly have moved.

This problem makes absolutely no sense but it happened anyway.

[Cadillo]

Is there any possibility that the die lock ring moved from its previous position? That has happened to the best of us, and to me on more than one occasion, depending on the type of lock ring used. There are only so many possibilities.

I would try loading a few more rounds and stop and look carefully at each completed cartridge hoping to find the gremlin.