Do Not Crimp

[Nomes]

I just started to get ready to reload the die set I just got said not to crimp the 9mm I want to reload.
Why?

[Frenchy]

I just started to get ready to reload the die set I just got said not to crimp the 9mm I want to reload.
Why?

9mm is not a crimp load, the shell is actually conical although you would need a good instrument to measure this, and the top of the bottle head, is part of what makes the round stop in the bbl.

[ar15jules]

9mm is not a crimp load, the shell is actually conical although you would need a good instrument to measure this, and the top of the bottle head, is part of what makes the round stop in the bbl.

In other words, the lack of a crimp, roll or taper, is what properly head spaces the round.
Jules

[Steve in PA]

You taper crimp the 9mm, you do not roll crimp.

The taper crimp will hold the bullet in the case. If you do not taper crimp you run the risk of bullet set back which could raise the pressure of the round. Something you do not want.

With a taper crimp you do not loose the edge of the case which is used for proper headspace.

Use a roll crimp and you will loose this edge causing the round to seat deeper in the barrel. Another thing you do not want.

[daschnoz]

If you don't already have it, get the LEE factory crimp die. It not only applies the taper crimp, but it does a final sizing on the OD of the case. I have not had a chambering problem since I started using this die.

You may just want to get the factory crimp die for every caliber you reload for. You will never seat and crimp in one step again.

[Nomes]

I have a
Layman A-A reloading Dies 3 piece set
Will that do the same as the LEE set?

What is the rite way to set the bullet in the case?

[daschnoz]

Nope. The 3 die sets give you:
- decapper/resizer
- case mouth flare
- seating die

The factory crimp is another die entirely.

The seating die also gives you a crimp of some sort to remove the case mouth flare that is added to make bullet seating easier. This is usually a roll type crimp.

{jedi mind trick}
You want the factory crimp die. It is the die you are looking for. Move along.
{/jedi mind trick}

[Frenchy]

Nope. The 3 die sets give you:
- decapper/resizer
- case mouth flare
- seating die

The factory crimp is another die entirely.

The seating die also gives you a crimp of some sort to remove the case mouth flare that is added to make bullet seating easier. This is usually a roll type crimp.

{jedi mind trick}
You want the factory crimp die. It is the die you are looking for. Move along.
{/jedi mind trick}

So this is the Die for crimp eh!... Wonder how many Die to get it...

Wonder if any one gets the jest in my words...

[Jake Mc.]

Agreed, I use a lee factory crimp die on every round I make, and recommend the same to everyone who asks. BTW what die set are you using that said "not to crimp 9mm"?

[notenoughguns]

9mm is not a crimp load, the shell is actually conical although you would need a good instrument to measure this, and the top of the bottle head, is part of what makes the round stop in the bbl.

????????????? /????????
Been loading 9mm for 30+ yrs and have always taper crimped , then again I use cast bullets . So now your going have to show me what I've been doing wrong ( at the next group shoot ) . I'll bring a caliper and a few bullets