Anyone not use the crimping die on 10mm loads?

[spitboy]

I use only load starline brass in 10 mm if I didn't crimp am I asking for trouble??

Edited March 18, 2015 by spitboy

[Hi-Power Jack]

Eric, I presume you're belling the cartridge case to make it easy

to seat the bullet.

If you don't remove the belling, the cartridge won't fit into your

chamber.

"Crimping" is really the wrong word here - we "crimp" for heavy

revolvers to keep the bullet from working out with heavy recoil,

but with semi-autos we don't really "crimp", we remove the

belling.

Removing the belling seems to be mandatory if the cartridges

are to feed properly.

[jmbaccolyte]

+1. Better than I could say it.

[spitboy]

Eric, I presume you're belling the cartridge case to make it easy

to seat the bullet.

If you don't remove the belling, the cartridge won't fit into your

chamber.

"Crimping" is really the wrong word here - we "crimp" for heavy

revolvers to keep the bullet from working out with heavy recoil,

but with semi-autos we don't really "crimp", we remove the

belling.

Removing the belling seems to be mandatory if the cartridges

are to feed properly.

Yes I guess that is what I'm doing but I thought that was also keeping the bullet from working out under recoil.

Thanks for the response...it's giving me a new perspective

[Hi-Power Jack]

Another misconception is that crimping is necessary to hold the bullet

in place (not pushing back into the brass, or setback).

That's accomplished by the sizing die, believe it or not -

by making the case tight, the case holds onto the bullet and won't

allow it to shorten - called bullet setback.

Setback is dangerous. If you set your OAL at 1.25" and the bullets

get setback to 1.15", you can increase pressure dangerously.

As you're setting your crimp, you should try to push some bullets

back into the case (push very hard) and then measure the new

OAL. It shouldn't be shorter than before you pushed the bullet

back.

If it is, then you have a sizing die problem and the answer is

not to increase the crimp.

[spitboy]

Another misconception is that crimping is necessary to hold the bullet

in place (not pushing back into the brass, or setback).

That's accomplished by the sizing die, believe it or not -

by making the case tight, the case holds onto the bullet and won't

allow it to shorten - called bullet setback.

Setback is dangerous. If you set your OAL at 1.25" and the bullets

get setback to 1.15", you can increase pressure dangerously.

As you're setting your crimp, you should try to push some bullets

back into the case (push very hard) and then measure the new

OAL. It shouldn't be shorter than before you pushed the bullet

back.

If it is, then you have a sizing die problem and the answer is

not to increase the crimp.

Thanks!!

Edited March 19, 2015 by spitboy

[spitboy]

Silly question...If we're not really crimping why is the dillon die stamped "crimp die"?

[gandog56]

Another misconception is that crimping is necessary to hold the bullet

in place (not pushing back into the brass, or setback).

Yes a very LARGE misconception. You do not crimp to increase neck tension. You crimp to equalize neck tension.

[jmbaccolyte]

Silly question...If we're not really crimping why is the dillon die stamped "crimp die"?

I don't know, tradition maybe. I agree with Hi-Power Jack on this though.

Another misconception is that crimping is necessary to hold the bullet

in place (not pushing back into the brass, or setback).

Yes a very LARGE misconception. You do not crimp to increase neck tension. You crimp to equalize neck tension.

Equalizing the case's neck tension may be a significant benefit, but I remove the flare of the case mouth so the cartridge chambers perfectly in semi-auto reloads like my .40S&W and "crimp" heavy .44 magnum revolver loads.

Edited March 31, 2015 by jmbaccolyte

[gandog56]

I had the Lee Dies for 10mm, and was using the Factory crimp die. This was all right for jacketed loads, but not so good when I went to powder coated cast loads. I got a Redding Taper crimp die. This did not put a ring around where the bullet was crimped through the powder coating.

[Forrest Halley]

So if I were to have made a mistake and over crimped my loads...I could essentially remove the decapping element from the sizing die and run that to correct the problem? Why not run a U die as stage one and a stripped regular sizer as the stage after the bullet seating?

I have done this in a pinch before to correct ammo that didn't case check, but I worried apparently unnecessarily about compromised neck tension.

[Daft]

I had some trouble feeding some plated reloads so I recrimped them with more authority. Yes, you could remove the bullet and there was a ring or indentation. Worried, I burn them up at the indoor range. These were light loads and they paper just fine. I think the problem feeding was not the case getting stuck up the ramp but the light recoil spring I put in it right after getting it.

[IATURNKEY]

From my recent experience with plated bullets, I turned my crimp way back and found accuracy to improve greatly. When using a Hornady or hard cast bullet I had the crimp die turned down about 2 more turns and accuracy was never an issue. I am now of the opinion that you only need to remove the bell from the expander die and have the cartridge drop easily into a case gauge.

[Glockenspiel]

Very interesting. Definitely seems to be the case that removing the bell is all that is required.