Does this crimp look ok to you?

[Matabele]

Hi all,

Tried my hand at loading up some 44Mag cast boolits for the first time, and had a range session with my SBH. The chrono was showing velocities were dropping with every shot, and It seems bullets were jumping the crimp.

So I have put a heavier crimp on the second batch of rounds This is what they look like, does that look ok to you?

From what Ive read the crimp shouldnt be too heavy as it can damage the bullet, and reduce neck tension leading to jumping the crimp. So does this crimp look ok?

http://i152.photobucket.com/albums/s194/Tamboti/Crimp.jpg

Any input appreciated, thanks!

[MtGun44]

Looks good to me. You must be using a taper crimp die, it looks a bit more tapered, less
abrupt than what most die sets do for revolver cartridges. Should be fine.

Bill

[Mohavedog]

I agree, looks like a taper crimp. I believe a roll crimp is more effective on revolver cartridges. You can put heavier or lighter roll crimp according to how hot you load. IMO roll crimp fits into the crimp groove better without damaging the boolit.....Mohavedog

[Iron Mike Golf]

I recommend a Redding Profile Crimp die.

[44man]

Taper crimp to be sure and way too much. You are lacking case tension big time. Boolit too soft? Or bad dies? You should see the boolit base and indications of the GG's through the brass.
CRIMP WILL NOT SAVE YOU!
That crimp is ruining the boolit below it. All that is needed is a roll crimp to the bottom of the crimp groove without digging into the boolit or moving brass.
Excuse my cheap camera but this is what a load should look like.

[44man]

One other thing I forgot, get rid of the magnum primers. They move boolits before ignition and give you all kinds of case capacities in the small .44 mag case.

[Matabele]

Thanks for the replies everyone. Im using RCBS dies, Im guessing from your comments they will only taper crimp then? What dies would you reccomend to get a good roll crimp and produce an accurate round?

Iron Mike what is a profile crimp, is it different from a roll crimp?

Thanks again, learning a bunch!

[MBTcustom]

lee collet crimp dies are awesome.

[williamwaco]

[QUOTE=Matabele;1334249]Hi all,

Tried my hand at loading up some 44Mag cast boolits for the first time, and had a range session with my SBH. The chrono was showing velocities were dropping with every shot, and It seems bullets were jumping the crimp.

QUOTE]


This is not rocket science. Don't over analyze it and don't spend more money on dies until you can't make it work. Don't ask a chronograph to tell you if you are jumping the crimp. Load up six cartridges. Fire five. Remove the sixth and see if it jumped the crimp. If it didn't your crimp is fine. I had exactly the same issue when I graduated from the .357 Mag to the .44 mag. The level of crimp I was accustomed to was significantly too light. By the fourth or fifth shot the unfired bullets had moved forward enough to lock the cylinder.

The crimp on the left looks inadequate to me. The crimp on the right looks marginal. Looks are not the way to judge it. Judge it by firing and use the lightest crimp that will hold the bullet in the case.

This is my test procedure for determining the crimp amount:

Load a half a box, 25 rounds with the hottest load you will be using. Select one and color the primer with a bright red marker. Load up six including the red primer. Align the red primer so it will be the sixth cartridge. Fire five. Do not fire the red one. Remove the red cartridge and check it. If the bullet hasn't moved, reload five more and fire them. Remove the red one and check the bullet. If it hasn't moved, fire five more. If it still hasn't moved, you have a reliable crimp.

Remember less crimp = more loads. Don't crimp more than necessary.

Also remember, your .44 special loads do not need that heavy crimp, save your brass.

[lancojames]

Your crimp as it is will cause your cases to end split in five or six reloads, maybe less.

[Matabele]

Thanks for the input guys, I'll fire these off using your test William and see where we are. I agree only crimp as much as necessary.

[44man]

I have used every die made for the .44. RCBS has too large of an expander and made the most inaccurate loads until the expander was polished down.
I had BR dies made with collars and they work but are a real pain.
I found Hornady New Dimension dies equal the BR dies.
The Lee FCD can ruin brass and boolits.
The Redding profile crimp die is great unless boolits are too large to pass through the die because you are matching throats.
Without case tension, making the crimp harder and harder just makes things worse.
I never seen an RCBS die make the crimp shown, most have a regular roll crimp. Are they CA dies?

[Matabele]

44man, if you mean are they carbide then yes they are. They came in a grey box, and are about 3 years old. I wonder if they are a short run by RCBS before they changed back to roll crimping?

[44man]

44man, if you mean are they carbide then yes they are. They came in a grey box, and are about 3 years old. I wonder if they are a short run by RCBS before they changed back to roll crimping?
The carbide size die is good. It is only the expander that was too long and large in diameter.
I have no idea what they have done with crimp dies. There seems to be nothing set in stone. I have Hornady crimp dies labeled "taper crimp" that only roll crimp.
Lyman is in the dark ages with soft lead. The "M" die can be a disaster in a revolver. I bought a Lyman neck size die for the 45-70 BPCR and over size boolits fall in the necks without expanding.
It gets very confusing.
The only thing I have found is that the dies can make or break accuracy real fast.

[oscarflytyer]

With cast, my RCBS Carbide dies roll crimp fine. The case expander, OTOH... I stopped using the RCBS case mouth expander and went to the Lee die. The taper plugs are much more gradual than the RCBS taper plug.

As mentioned, with cast, you want good case tension. Mine got much better when I went to the Lee expander die.

[subsonic]

If you have a dial caliper, slide it down the cartridge holding light pressure against the case and watch the dial. If the case gets larger right before where the crimp rolls in, you have buckled the case with too much crimp. The case should be larger where the boolit is seated, but be the same size from the bottom of the boolit right up to the crimp.