How can you tell it you have crimped too much, or not enough?

[stev32k]

I've been trying to decide how to set the seating/crimping die. The seating part is easy, but there is really nothing to measure for the crimp. I've been giving the cartridges the whack test - that is put them in a hammer type bullet puller and see if it takes a hard whack to get the bullet out.

That seems like a pretty crude test, but have not really found anything else to go by. The last rounds I pulled had an indentation around the bullet where the case had been crimped and I wonder if this is normal or indicates too much crimp?

[soundguy]

can i assume you are talking baout a rollcrimp die setup.. like an rcbs might use on a rifle die set?

the brassh will just start to lay over into the cannelure. too much and you are way overflexing and workign the brass and that will lead to early mouth/case failures.

do the push in test to see if the bullet cnnot be pushed in by pressing a dummy cartridge into your workbench. if you can get like 50# on it and no setback.. it's held in good.

excessive crimp isn't desireable.

[ozo]

And too much can cause high pressures.

I use Lee carbide dies [yes, in my Dillon]
and mine are an easy adjust....
Remove the seating adjustment 'pin' or
at least back it way out......
Using an empty case, slowly screw the die
in the tool head, little at a time, checking
the case mouth with a micrometer.
Your instructions that came with the dies
should show you how.

[soundguy]

Originally Posted by ozo

.
Your instructions that came with the dies
should show you how.

^^^^^^ YUP

same with the rcbs roll crimp...

[stev32k]

My die sets (Hornady) don't give a clue as to how much crimp to put on the cartridge. It tells you how it's done, but says nothing about the amount.

[stev32k]

Originally Posted by ozo

And too much can cause high pressures.

I use Lee carbide dies [yes, in my Dillon]
and mine are an easy adjust....
Remove the seating adjustment 'pin' or
at least back it way out......
Using an empty case, slowly screw the die
in the tool head, little at a time, checking
the case mouth with a micrometer.
Your instructions that came with the dies
should show you how.

How much should the crimp reduce the diameter of the case?

[soundguy]

Originally Posted by stev32k

My die sets (Hornady) don't give a clue as to how much crimp to put on the cartridge. It tells you how it's done, but says nothing about the amount.

that's where the reloading manuals come in.

On mine.. I crimp till i just see the leading edge of the brass start to aly over into the cannelure, and they also pass a hard push test. if they do that.. they will be fine for no-setback in a magazine.

[mikld]

Well, what type of crimp are you using on what cartridge? From what is hinted about so far, sepatate the seating from crimping operations (seat all bullets then readjust die and crimp all cartridges).

[stev32k]

Originally Posted by mikld

Well, what type of crimp are you using on what cartridge? From what is hinted about so far, sepatate the seating from crimping operations (seat all bullets then readjust die and crimp all cartridges).

I'm reloading 9mm and using the Hornady seating and crimping die. The Hornady manual says "use little or no crimp". If I don't use any crimp the bullet is loose in the case. So I tried turning the crimp down 1/2 turn after it made contact with the case. That's where my problem is - is 1/2 turn a little crimp or a lot? Maybe it should be 1/4 or 1/8 or 1 full turn for a "little crimp".

[soundguy]

ahh.. pistol, not rifle!

[312shooter]

A 1/2 turn is good. Excessive resistance on the press handle is clear indicator there is too much crimp. A good way to measure a proper crimp is using calipers near the casemouth after bullet seating, compare the measurement to the dimension of the sum of the bullet and case thickness x2 prior to seating.

[mikld]

Originally Posted by stev32k

I'm reloading 9mm and using the Hornady seating and crimping die. The Hornady manual says "use little or no crimp". If I don't use any crimp the bullet is loose in the case. So I tried turning the crimp down 1/2 turn after it made contact with the case. That's where my problem is - is 1/2 turn a little crimp or a lot? Maybe it should be 1/4 or 1/8 or 1 full turn for a "little crimp".

When reloading semi-auto ammo, ferget the term "crimp". You will be using a taper crimp die just to "deflare" the case mouth. All you need is to remove any flare in the case mouth so chambering is easy. Use your gun's barrel (removed) as a gauge. If the bullet is loose in the case prior to "deflaring", there is a problem elsewhere (sizing/expanding/bullet dia.). Again, separate operations; seat, crimp.

[runswiththunder]

I use the Lee Factory Crimp die, so I'm not familiar with the Hornady die. To check my crimp, after seating the bullet I measure the case just at the mouth, then adjust the die to create a crimp of about .005+. To check the tightness, you can place the bullet on the edge of your table and press against the base of the cartridge. If the bullet stays put, with a few pounds of pressure, it's probably crimped sufficiently.

[cpttango30]

too much crimp and your round will fall into the chamber too much. Just check in your barrel.