9mm crimp

[ghawk249]

Just started to load 9mm using 124gr fmj rn Precision Delta bullets. I was wondering what crimp everyone used?

[Kentguy]

ghawk249,

I use LEE carbide dies, so I always put a "light" crimp on my 9mm fmj rounds - 1/2 turn on the crimp die.

[F106 Fan]

Straight wall cartridges (yes, the 9mm is tapered) don't get a crimp. All you need to do is close up the case mouth.

The easiest way to do this is with a separate taper crimp die. This die is easier to adjust that a normal crimping die because the normal die wants to roll a crimp.

You should be able to pull a bullet and see that the case mouth did not dig into the surface. This is very important when using plated bullets so as not to damage the very thin plating.

Richard

[unclebob]

Just enough to remove the bell on the case.

[WiskyT]

Seat a bullet on a charged case and don't crimp it. Take the barrel from your field stripped gun and try to put the uncrimped round into the chamber. Likely it won't fit, if it does, it will be hard to get it back out. Now use your seating die to add a tiny bit of crimp and see if it fits. Keep doing this in small increments until the round chambers and falls free easily. Then add a tiny bit more crimp to ensure sufficient crimp on the occasional short piece of brass. Lock the die body down and adjust the seating stem so it firmly touches the completed round you worked with. You should now have a minimally crimped round with the desired OAL every time you seat a bullet.

[unclebob]

Seat a bullet on a charged case and don't crimp it. Take the barrel from your field stripped gun and try to put the uncrimped round into the chamber. Likely it won't fit, if it does, it will be hard to get it back out. Now use your seating die to add a tiny bit of crimp and see if it fits. Keep doing this in small increments until the round chambers and falls free easily. Then add a tiny bit more crimp to ensure sufficient crimp on the occasional short piece of brass. Lock the die body down and adjust the seating stem so it firmly touches the completed round you worked with. You should now have a minimally crimped round with the desired OAL every time you seat a bullet.
So what barrel do you use when you have 7, 9mm and 5, .45? Among others. A case gauge works a lot better.

[cysoto]

Just started to load 9mm using 124gr fmj rn Precision Delta bullets. I was wondering what crimp everyone used?

With 124gr Precision Delta (as well as Montana Gold) FMJ's & JHP's I use a crimp of 0.377".

[WiskyT]

So what barrel do you use when you have 7, 9mm and 5, .45? Among others. A case gauge works a lot better.

All my guns are normal sized, so I have never had a problem with a round fitting one gun and not another.

[tac_driver]

+1 .377