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Having a problem with bullet setback. Using berrys 124 grain 357sig bullets and lee dies including the Lee FCD. After crimping some ,I was able to push the bullet several thousandths back with my finger. Some were ok but others not. I feel like it is a crimp problem but not sure. Been loading 40, 9 and 762x25 with no problem. Any suggestions? Thanks
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measure your neck tension on a just fired case.
if you have about .002 tension already you got enough.
then I would measure the bullets, it wouldn't surprise me to see 355 on the plated bullets.
if you got problems after that I would fully suspect the LEE case squisher die is your issue.
many plated bullets are soft lead and when they enter the die they squish down and the case springs back slightly.
You can over crimp.
I used a Redding taper crimp die when I was loading for the 357 Sig. I was using jacketed bullets though. I did not have a problem with set back after using the taper crimp die.
As Tackleberry said overcrimping will cause bullets to be loose, kind of counter intuitive.
I powder coat the cast bullets used in the 357 SIG and size the bullets to .357. I also use the Lee factory crimp die. The crimp applied to the powder coated bullet is just enough to hold the bullet but not damage the powder coat. A test is made by pulling the bullet with a inertia type bullet puller. When the bullet is pulled the powder coat should still be intact but the bullet is still belt in place with the crimp. It takes a few tries at adjusting the factory crimp die to find the correct crimp amount. The same cast bullet is used for the 38 Special, the reason for sizing to .357.
The bullet mold came from Accurate Molds and is used in an Automated Master Machine.
I designed the bullet and Tom at Accurate made the mold, the cast bullet has a weight of 125 grains. The bullet is plain base and a homemade gas check made from .010 aluminum roof flashing is installed.
Even using the rifle collet type FCD that the OP is using? I've seen rifle jacketed bullets ruined by over crimping using these type of dies but never a report of them being loose, with a regular crimp die sure, experienced that myself, but not with the collet FCD.Quote:
Originally Posted by kayala
That FCD is adjustable, your not crimping hydraulic lines. Just a touch of crimp is all you need. Neck tension is what holds things in place, not the crimp. If it had a crimp groove, fine, but factory ammo doesn't use it. Dont really need more crimp than a 9mm or 40. Those plated bullets are not much different than cast. Yo ucrimp, the brass springs back, the lead doesn't. Now its looser than when you started.
Thanks to all, I will adjust the crimp die further (less) and see how it goes. Great knowledge here.
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Fritoguy, is there a reason you're crimping at all? People are right about the possibility of over crimping. Brass springs back, lead does not.
If you are concerned about setback then you should check neck tension first. Measure the bullet diameter and measure the case neck ID after the sizing operation. .002-.003" tension should be fine. Make sure you clean off any sizing lube that may be in the case neck.
You can test for setback in your pistol just by vigorously cycling loaded ammo, operating the slide manually, and measuring pre and post cartridge lengths. It's my opinion that setback is not necessarily a bad thing so long as it's a reasonable amount, that's repeatable and consistent as not to risk overpressure, cause extremes in velocity or affect the feeding/reliability.
Personally, unless there's a reason for it, I would not bother with the crimp. To the best of my knowledge I've never had an issue requiring a crimper to fix even after 8,000-10,000 rounds of 357sig.
Only reason I use the crimp die w my cast 357 sig, to get rid of the flare I use to get the cast in the neck. They aren't really crimped.
What size are the bullets? I go with 0.356" as a min in plated, lead or coated. A 0.357" is even better, giving you more neck tension. I just use the Dillon TC die to finish. I did polish my powder thru expander down 0.0005" for a bit better neck tension with jacketed. Another oft recommended test for neck tension is nose down on a bath scale. You want 40# min pressure.
My experience loading .357 SIG with several different CB designs is that enough crimp is a must. Some folks use a full case of slow burning powder to counteract set-back, but I prefer to rely solely on neck tension and crimp, and if the powder is helping too, great. With a powder like AA #9 or 800x, it is usually going to prevent set-back on its own, but I crimp until I can push that round against my bench pretty hard (35-40 lbs. pressure) and have the bullet stay put. I also use a .40 sizer followed by a .357 SIG sizer to eliminate the need for case lube. Personally, I have not experienced crimp creating a looser fit...there is some debate as to whether the round headspaces on the shoulder vs. the mouth, but I do not worry about a firm crimp creating problems with this bottle-necked cartridge, and it has not.
-BE
I believe i "May" have solved my problem, first i tried no crimp and could easily push the bullet all the way back. Then i started slowly increasing the crimp until i was no longer able to push it back at all. Actually took quite a bit of crimp to reach that point.
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This is exactly how I set mine up. I absolutely don't want any bullet setback w/ this cartridge. If I can push the bullet in by placing it bullet first on the bench and pushing on the case then I don't have enough crimp. Short bottle necked pistol rounds a whole different animal to load for. Loading jacketed rounds is no different when it comes to crimp. The bullet needs to stay in place.Quote:
Originally Posted by fritoguy
When you find your crimp sweet spot, as a final test make a dummy round and chamber it in your pistol. Load the round into a magazine and chamber it by dropping the locked slide forward. Eject the round, measure and repeat. It can be tough to find the sweet spot with the SIG round. Minimum case flare and not overcrimping are the keys to success.
... so much drama. I've never had an issue, cast or jacketed.
Using the method described by chuck Perry above, I find commercial straight wall cartridges (9mm, .40s&w etc.) still set back some when the projectile's hammered into the feed ramp. The 357Sig is no different to load for in my opinion. Do the due diligence and you'll have no problems.
Fritoguy, I'm glad you got it figured out.
Hold on a sec, you don't really have the problem solved yet. The part I highlighted bold should be a clue that you don't have enough neck tension; fix that first, before trying to band-aid it with crimp. The 357 Sig has so little neck anyway, that you really need to get the neck tension right.Quote:
Originally Posted by fritoguy
Your expander ball is probably a little large, and/or your bullets are too small. I'm betting on a bit of both, and the soft swaged/plated bullets aren't helping. A harder bullet (either cast or jacketed, skip the plated stuff for this round IMO) and adequate neck tension will go a long way toward fixing your problem. Use the crimp as the suspenders to go along with the belt, not as the sole method of holding the bullet in place.
I agree. If i can't solve the neck tension problem, i do not think it is safe to reload
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