Running loaded rounds through sizing die

[Hockey7711]

Is it ok to do a final resizing after a cartridge is loaded? One of my 380 pistols has difficulty chambering some of my reloads. My other 380 doesn't have a problem.

 

[The Glockodile]

Hm.

Not sure.

BUT, Lee does make a die which does some last - pass sizing of the cartridge as it (seats and) crimps the assembled round (primer + powder + bullet).

So I guess it would be okay.

 

[Hockey7711]

I think that I belled the case mouth a bit too much prior to seating the bullet, and after the bullet is seated there is a small ridge which may be slightly larger in diameter than the bullet.

 

[The Glockodile]

In that case - there may be an issue with your crimping step.

There shouldn't be any residual "bell" after crimping (I think).

Speculation on my part.

 

[Bob Meyer]

I've done it with no bad consequences.

 

[Bcwitt]

I have done that, & i found it loosens the crimp.

 

[tightgroup tiger]

Are you wanting to resize them with your resizing die? I wouldn't do it with a regular resizing die, you will undersize the bullet to a smaller diameter.

You are looking for Lee's Factory Crimp die. You want the one with two carbide rings. It will resize the completed round while crimping it.
I don't use them myself, but a lot of members here do.

 

[Hockey7711]

Ok, sounds good. I have a lee 3 die set for the 380. It didn't come with a crimp die.
That would probably do the trick.
I do have a 9mm crimp die, would that work?

 

[Charlie98]

Ok, sounds good. I have a lee 3 die set for the 380. It didn't come with a crimp die.
That would probably do the trick.
I do have a 9mm crimp die, would that work?

It most likely has the crimp die built into the seater die... typically with autoloading cartridges, it's a taper crimp, which is what you need. If you still have them, have a look at the instructions that came with the dies.

 

[Hockey7711]

I was able to order a factory crimp die just now.
Thanks

 

[Otto]

^ In 3 die sets, the seater die also crimps....you do not need a FCD. .

 

[CoalTrain49]

^ In 3 die sets, the seater die also crimps....you do not need a FCD. .

It crimps but I think the OP's problem is the size of the finished round won't chamber in one of his pistols. I use range brass so about half of my finished ammo won't pass a gauge test. The FCD takes care of that. It adds a step to the process but it also re-sizes the finished round to be within tolerance. It also crimps and the crimp is easily adjustable. Seater/crimp dies are a PIA to adjust because you have to re-adjust the seating depth when you mess with the crimp. I have FCD's for all my pistol ammo. Never found a use for them with revolver ammo that use roll crimps however.

Seat and crimp in separate operations and save yourself some grief.

 

[MEHavey]

If all you have as an issue is insufficient tapering back to SAAMI mouth spec... NO PROBLEM

Pull the decapping pin out, seat the die maybe only two turns into the Press, and run the loaded round up into it.
You'll just barely feel any engagement, but it will likely be enough to taper the case mouth back in.
Try plunking the round....

There is nothing wrong w/ using the sizing die that way.
In fact I use in on my two 350 Legends as a matter of standard practice.
https://thefiringline.com/forums/showpost.php?p=6807773&postcount=49
Excellent "de-taper" technique.

 

[Hockey7711]

Thanks

 

[Walkalong]

No, do not try to fix a loaded round with the sizer for that round, it will do more damage than good, fix the issue instead.

That said, Lee is ahead of you on this, and makes the FCD for pistols with a “post sizing” carbide ring, which, by the way, has a larger ID than the sizer for that caliber.

 

[kcofohio]

Is it ok to do a final resizing after a cartridge is loaded? One of my 380 pistols has difficulty chambering some of my reloads. My other 380 doesn't have a problem.

Are you checking the cartridge in the chamber doing the plunk test? Do they pass or fail there?

 

[Hockey7711]

New gun haven't checked yet.

 

[ACES&8S]

Always start new weapons with factory ammo, I guess you have done that already.
I have a Lee factory crimp die for every caliber I reload. I use that or no crimp at all.
You are going the right way.

 

[Hockey7711]

It does work fine with factory ammo.

Is there such thing as a break-in period?

 

[kcofohio]

Or it could be different bullet profiles. I'd make up some dummy rounds and adjust seating depth to see what will feed into the chamber.

 

[Hockey7711]

Good idea

 

[ballman6711]

I think that I belled the case mouth a bit too much prior to seating the bullet, and after the bullet is seated there is a small ridge which may be slightly larger in diameter than the bullet.

I did this exact same thing about a week ago in 45acp (instead of 380). Too much bell and after crimping they wouldn't plunk in my barrel. Initially I thought I hadn't crimped enough, and tried adjusting my die and re-crimping. No luck.

I then thought about running them through the sizer again with the de-priming pin removed, but was concerned that would ruin my bullet tension and possibly result in setback when chambering. Decided not to do that.

So this morning I took a clean, used piece of brass and started fresh making a dummy round. Sized it and checked for fit in the barrel. Perfect fit. Next I adjusted my flare die to just barely flare the brass, and made adjustments until the bullet just sat straight. Seated the bullet and checked for bulges. Looked good. Crimped and measured, it was a bit tight on the crimp, but it passed the plunk and spin test. I made two more with minor adjustments and both plunked fine.

Then I made two live rounds, and again both passed the plunk and spin test.

I've decided to to pull the assembled rounds and just chalk it up as a learning experience. Just my recent experience in the last week.

chris

 

[PWC]

Back out the seater and run them thru the die to remove the bell.

 

[9mmepiphany]

I think that I belled the case mouth a bit too much prior to seating the bullet, and after the bullet is seated there is a small ridge which may be slightly larger in diameter than the bullet.

Are you talking about a "ridge" at the case mouth; not crimped enough or are you referring to a "ridge" where the base of the bullet would be inside the case?

 

[jmorris]

I have done that, & i found it loosens the crimp.

Yep. Lead is pretty much dead soft. Brass is much more “springy”. This is why dies to size brass are “under” dimension, to accommodate for spring back.

So you squeeze the case back down, and the bullet inside it and the case springs back larger but the bullet stayed the smaller diameter. Now you are worse off than before.

Even if you roll crimped them so it could “grab” vs using neck tension, you would most certainly have changed the diameter enough to destroy accuracy.

People that know better than to turn out crummy products, sell the damaged projectiles as “pulled” bullets. The marketing department keeps them from calling them, “fell out during post load tumbling”, bullets.



They are a deal because they are as accurate from your firearm as they would be thrown by hand, by the fist full.