Shoulder Bump

[Jcalloway8603]

So we not to hijack another thread, I figured I would start my own. I've been loading for several years now, but mostly dealt with new or once fired in my gun. I bought some once fired for my 7mag that I'm going to be loading soon. I had a thought. I've always bumped the shoulder with a full length die .001 when loading shells fired out of my gun. But what if with this new batch that is once fired, but not out of my gun, I find the shortest shoulder that fits my gun and bump lol of this new brass with that length? Does it make sense on what I'm saying? I would think with the full length die, it would work. But never tried it and didn't want to waste a bunch of time on the brass only to go back and redo it. Thanks in advance.

 

[Mikecr]

Never default to the wrong of anything.
I would fully fire form the brass in MY chamber, creating a case that represents MY chamber, and then size to MY plan.

 

[sedancowboy]

I am just thinking out loud here. If your die is set to bump the shoulder back .001 then it would stand to reason that all of the once fired brass would either be bumped back to your dimension or you would not reach the shoulder. Either way they would fit in your chamber and after firing they would be fireformed to your chamber. It could not be longer provided that your die is locked, you use the same shell holder and it is hard against the die at the top of the stroke. I would check over all length after I sized them to make sure some were not too long. In other words all cases would be sized to your die setting or they may be shorter. They could not be longer at the base to datum line.

 

[Rich Coyle]

Once you full length size them, run EVERY one through the action before you go any further.

 

[Mikecr]

Always measure the actual bump.

 

[Jcalloway8603]

That's kind of what I was getting at. They would be either right where I need them, or maybe a bit shorter depending on the gun they came out of. I hate to waste powder and Bullets further fireforming especially because of the powder shortage for my 7 mag around here. Also I don't have a annealer and I don't want the brass getting to hard which is even further more inaccurate.

 

[Jcalloway8603]

I also thought about measuring everyone of them and finding the shortest, and bump everyone down to match that one for now and load testing.

 

[Mikecr]

No matter where from or what your brass is, you'll have to burn the powder to form it as stable & consistent in your chamber. Sooner, or later.

 

[Rich Coyle]

I also thought about measuring everyone of them and finding the shortest, and bump everyone down to match that one for now and load testing.

Why!? Run them through your present setup and fire away.

 

[Jcalloway8603]

Why!? Run them through your present setup and fire away.

True!

 

[Jcalloway8603]

I guess I could use some cheap Bullets.

 

[Jcalloway8603]

When fireforming, do ya'll just use a minimum charge or is it important to get it hot so the brass gets a good seal?

 

[Hondo64d]

So we not to hijack another thread, I figured I would start my own. I've been loading for several years now, but mostly dealt with new or once fired in my gun. I bought some once fired for my 7mag that I'm going to be loading soon. I had a thought. I've always bumped the shoulder with a full length die .001 when loading shells fired out of my gun. But what if with this new batch that is once fired, but not out of my gun, I find the shortest shoulder that fits my gun and bump lol of this new brass with that length? Does it make sense on what I'm saying? I would think with the full length die, it would work. But never tried it and didn't want to waste a bunch of time on the brass only to go back and redo it. Thanks in advance.

I would resize the brass so that it measures .001 to .002" less than the brass you normally use in that chamber and then make sure they chamber ok.

If they won't chamber with a headspace measurement .001 to .002" less than brass fired in your chamber, then it is possible your die is not sizing the case small enough immediately in front of the belt to chamber in your rifle. Should that happen, you might squeeze it down by screwing your die down farther but that will increase the headspace and weaken the brass further on firing in your chamber. Better solution would be the Willis Collet die or a small base die if anyone makes one for a 7 Mag. Another option that I have used was to have the top of a die cut off so it doesn't push the shoulder back at all but sizes the body above the belt.

Were it me, rather than go to the additional expense of a Willis die or modifying a conventional FL die, I'd size them to .001 to .002" shorter than brass fired in your chamber and if they don't chamber well, trash them or sell them.

If you absolutely want to use this brass I have a Willis Collet die I'd let go very reasonably, as I'm not shooting any belted mags any more.

John

 

[Jcalloway8603]

Thanks sir. I will let you know.