Crimp for 9mm?

[ronas]

How can you if you have sufficient crimp on 9mm round?

I'm using a dillon taper crimp die, 115 grain FMJ, and will be used in Berrata 92.

[J-cat]

The crimp is sufficient when you remove the bell from the case mouth.

[Sheldon]

Your casemouth tension should be what's holding the bullet in the case. As mentioned the crimp in semi-auto calibers usually is to remove any belling on the casemouth.

[new cal shooter]

Remove your pistol barrel and drop your finished round in it if they go in slick and smooth, your almost there, just turn the die down until you see a slight mark on the end of your cases, like it wants to start to "roll" the case, as long as it fits easy and does not roll the end of your brass into a roll crimp, you brass should have a flat surface when it touches the chamber / barrle area, at least this is how I do it, others may vary,

Get a Wilson chamber guage, excellent tool! acts like a chambe saves you time.

[Revoman]

I usually start with a light crimp, measure that OAL, then use the side of my wooden bench to put pressure on the base of the round while the bullet is against the wood. I'd guess around 10 lbs of force with my thumb.
Then re-measure the OAL, if it is shorter than the first measurement, then the bullet slipped into the case a bit, sometimes you can actually see it slip. Try it again with another round or use a bullet puller and reuse the same round. Do this same test until the bullet does not slip into the case anymore, using small adjustments on the crimp die. You want the crimp to be just enough to hold the bullet in place.
Seems so work for me.
The real danger in the bullet not having enough hold is that the recoil can push the bullets in the magazine deeper into the case, just like you are doing with your thumb, which carries higher pressure, which is not a good thing.

[J-cat]

Adjusting the crimp until the bullet stops slipping has never stopped the bullet from slipping in my experience. It is case tension that stos the slippage. You adjust case tension by reducing the diameter of the expander plug.

[new cal shooter]

As J-cat Said

"You adjust case tension by reducing the diameter of the expander plug"

Excellent advice, most plugs are way too Fat for jacketed bullets, take some 1000 grit sand paper and try and put the plug in a drill, spend a few seconds sanding it down a few rotations like 50 or so, give you much smoother operation also.

I had a Lee die for .38 that was very ruff, after sanding it was smooth and easy to bell my cases for lead cast boolits which take a slightly larger bell.

Good luck.