Crimping 9mm

All bullets don't need to be crimped, but 9mm's should have a taper crimp applied. The only real reason for them to have a crimp is to hold the bullet in place better as it hits the loading ramp....it keeps the bullet from getting shoved back further into the case.
 
Crimping 9mm (DUNITALL)

I use a slight crimp on my 9mm loads. It tends to chamber a little better for me , but it may also keep the bullet in place.
 
I use a taper crimp on all of my semi auto pistol loads,roll crimp on all of my revolver loads.
Not only does it keep the bullet seated during recoil and loading it also removes any neck flare that I add when expanding the case mouth.
 
One taper crimps(only) 9mm to keep the bullet in place and aid feeding. Even with light cast bullet loads the crimp will aid feeding.
Like Old Stony says, 9mm cartridges get pretty roughly handled while being fed into the chamber.
 
I agree, taper crimp 9MM.

FWIW, years ago a coworker showed me a fired 9MM case with a primer that was so flat it looked like a melted silver metal had been poured into and filled the primer hole edge to edge. Turned out he had been ROLL crimping his 9MM reloads, resulting in grossly excessive headspace. Ugly!
 
pappadoer asked:
Do you have to crimp "any" bullet.
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No.

On straight-walled cases (and even though it has a slight taper, we treat 9mm as straight-wall) it is generally necessary to slightly "expand" or "bell" the mouth to let the bullet seat. But since rimless straight-wall cartridges headspace on the mouth, crimping is generally not desirable and the seater die should be adjusted with just enough crimp to remove the "bell" imparted by the expander.

Remember, on straight-wall rimless cases, neck tension should be sufficient to hold the bullet in place. The crimp is not a substitute for properly sized brass with adequate neck tension.
 
I would be afraid of bullet setback without taper crimping 9mm,regardless of neck tension.
There is no logical reason not to.
 
No.

On straight-walled cases (and even though it has a slight taper, we treat 9mm as straight-wall) it is generally necessary to slightly "expand" or "bell" the mouth to let the bullet seat. But since rimless straight-wall cartridges headspace on the mouth, crimping is generally not desirable and the seater die should be adjusted with just enough crimp to remove the "bell" imparted by the expander.

Remember, on straight-wall rimless cases, neck tension should be sufficient to hold the bullet in place. The crimp is not a substitute for properly sized brass with adequate neck tension.
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Bingo...well said sir!!

Generally, the less "crimp" you can get away without bullet set back or in the case of a revolver load, forward movement, the better off you are accuracy wise. Testing for a secure bullet can be done by pressing the loaded round against your bench or even a bathroom scale and getting 40 lbs. of pressure. This procedure was recommended by none other than NRA's Ed Harris at one point in his career there.

In my personal use, I employ a minimal taper crimp with my 9mm, .38 Super, .380, and .45 ACP loads to remove the belling necessary to seat bullets straight and without shaving in the case of lead alloy. I've not had any 'set-back' issues with my handloads. HTH's Rod
 
FWIW, years ago a coworker showed me a fired 9MM case with a primer that was so flat it looked like a melted silver metal had been poured into and filled the primer hole edge to edge. Turned out he had been ROLL crimping his 9MM reloads, resulting in grossly excessive headspace. Ugly!
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That begs the question: What brand of 9mm dies comes with a roll crimp feature?
 
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I do not crimp any of my semi-auto handloads. I simply use a taper crimp die to remove any flare placed in the case mouth for easier bullet seating. I use as little as will allow good plunk testing. Neck tension has been sufficient for my 2, 45 ACPs and my 3, 9mms...
 
I do not crimp any of my semi-auto handloads. I simply use a taper crimp die to remove any flare placed in the case mouth for easier bullet seating. I use as little as will allow good plunk testing. Neck tension has been sufficient for my 2, 45 ACPs and my 3, 9mms...
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This!
 
crimp 9mm

hi, I too am getting into reloading for 9mm. Do you recommend the 3 or 4 die set for pistols, like the Lee dies with the extra factory crimp die?
reason I'm asking is that I purchased 1000 reloaded ammo from a dealer and about 10% would not feed in my pistol. would the FCD eliminate this problem?
Couldn't I just resize the loaded round to make sure it chambered?
 
danny 1, all my die sets are 4 die carbide Lee sets. It's always good to have the extra die, and more expensive to buy later . I do use them all.
 
You don't want to push the lip of an auto cartridge into the bullet. The 9mm, 10mm, 40 cal, etc headspace off of the lip You do want them to hold the bullet in place during recoil and also feed properly so a taper crimp is not a bad idea and may be necessary if you flared the mouth of the case to seat the bullet.
Rimmed cartridges like the 357 Magnum, 44 magnum, 38 spc, etc headspace off of the rim and you can crimp the crap out of those.
As a general rule you crimp the rimmed cartridges and do not crimp the auto cartridges.
 
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