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should a pulled 9mm bullet have a ring around it?


ProGunGuy

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I have been loading 9mm for many years and 10 of thousands of rounds with little problem. this is with lee dies and FCD.

I got a rcbs dies set recently and have been playing around with it. I just use the crimp/seat die as crimp die only in place of the FCD.

Now playing with the dies, the only way to make round that drop free is to adjust the dies till it has, what it seems, a light roll crimp. when i pull the bullet, it leaves a ring around the bullet. Is this normal?? my FCD does not do this.

bullets used are BC 147gr. I measured, as best as i can the crimp at .378-.379.

so am i doing it right??

Edited by ProGunGuy
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To much crimp can affect accuracy and may cause a bullet to keyhole, tumble. Mike the bullet in the case subtract .002,.003 for crimp setting. .380 crimp would set at .298.

I have used and recommend Lee Dies. Like Lee's first stage sizer and seating die if I'm using the FCD I back it up a little and use it as a crimp die.

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It's been a while since used a rcbs 3 die set,

But I seem to remember the combo seater/crimp die has a roll crimp, and if you wanted a tamper crimp,

You had to buy a separate taper crimp die

I would use the rcbs die to seat & your FCD to taper crimp

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i need to crimp it this much or it will drop freely from the chambers of my 9's.

your rounds should drop freely out of your chamber, if you crimp this much there is a big chance a case will get stuck in your riflings, and when this happens you get excessive pressure in your case, and it will blow up your gun.

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i need to crimp it this much or it will drop freely from the chambers of my 9's.

your rounds should drop freely out of your chamber, if you crimp this much there is a big chance a case will get stuck in your riflings, and when this happens you get excessive pressure in your case, and it will blow up your gun.

How's that gonna happen??? Just curious what you think is happening when a roll crimped cartridge is chambered.

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i need to crimp it this much or it will drop freely from the chambers of my 9's.

your rounds should drop freely out of your chamber, if you crimp this much there is a big chance a case will get stuck in your riflings, and when this happens you get excessive pressure in your case, and it will blow up your gun.

How's that gonna happen??? Just curious what you think is happening when a roll crimped cartridge is chambered.

9mm are supposed to head space on the mouth of the brass. If you crimp it that much- there is possibility that the case could essentially go into the barrel. That isn't desirable for a lot of reason. Don't know if it would blow up but I wouldn't want to try.

When you roll crimp a round it's usually for revolvers... which don't headspace on the case mouth!

Edited by lugnut
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Excessively crimping a coated bullet (or plated) can tear the coating. Causing any number of issues from accuracy to bore fouling. The only thing the taper crimp die is supposed to do is remove the flair from the expanding step.

If your reloads aren’t passing the plunk test with a normal crimp, something else is going on.

It could be your resizing die is not set right.

It could be your expander plug is slightly oversized.

It could be your case walls are to thick.

It could be your chamber is cut to tight.

Using an excessive crimp (or a magic crimp die) is not the solution, it’s covering up another issue.

Jeff

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i need to crimp it this much or it will drop freely from the chambers of my 9's.

your rounds should drop freely out of your chamber, if you crimp this much there is a big chance a case will get stuck in your riflings, and when this happens you get excessive pressure in your case, and it will blow up your gun.

How's that gonna happen??? Just curious what you think is happening when a roll crimped cartridge is chambered.

Don't know if it would blow up but I wouldn't want to try.

believe me it will, and hopefully it will only be the gun that is damaged

How's that gonna happen??? Just curious what you think is happening when a roll crimped cartridge is chambered.

comparing rolcrimped cartridges with taper crimped certridges, is like comparing apples to chestnuts.

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FCD one looks good to my old eyes... I would back the RCBS one off a quarter turn. A lot of this is purely academic - unless you are shooting PPC at 50 yards. If they both chamber OK and hold the X-ring of a Bianchi target at 25 yards then you are good to go for just about any action shooting.

I learnt long ago that if you can't hold the X-ring of a Bianchi target, then don't expect the ammo to. YMMV

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Being as you now have both a Lee set and a RCBS set. Run a case through both sizing dies and measure the sized case. Are they close to the same? They should both be just below .380 at the mouth and around .390 at the base above the extractor groove. If the mouth dimension is BELOW .380 you should be OK, if not then you have a problem with your sizing die. Then run the case through the powder drop/ bell die. What is the mouth dimension now? It should be at or just above .380 which is just enough for the bullet to sit on top of the case and not strip off the outer layer as you seat the bullet. Then crimp the cartridge leaving the top of the case where the mouth is at at around .378. It should drop into your chamber freely.

A quick test of the sizing and belling of a case is to try and force the bullet into the case by hand. IF you can slide the bullet into the case by hand then the cases are not being sized properly.

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