Bullet Crimp Questions

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haskins02

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I plan to begin reloading .308 Win (for Browning X-bolt). I plan to load Sierra bullets using the Lee Deluxe Rifle Die set (neck sizing + full sizing + seating dies). The bullets I plan to load do NOT have a crimp groove. I read that such bullets should NEVER be crimped in place using a bullet seating die, and that if crimping is desired, use a separate “factory crimp” die. I will be doing informal target shooting most of the time and occasional hunting.

Questions:

1. Do I really need to crimp these bullets?

2. Is it true I cannot use a bullet seating die to crimp bullets with no crimp groove?

3. Under what circumstances would I need a separate factory crimp die?

4. (on a related matter) If using reloaded rounds for hunting, I read that full case sizing, not neck-only sizing, should be performed. But does this rule still apply if my cartridges will be kept housed and protected in the X-Bolt’s detachable magazine (instead of loose individual rounds being loaded and unloaded from an internal magazine)?

Thanks.

Greg
 
No need to crimp at all for a bolt-action rifle.

Some do crimp for auto-loaders, but I'm not convinced that is necessary either.

I have done limited testing with a Lee FCD crimp on .223 on bullets without a cannelure.
If anything, there was no difference in accuracy.

I see no reason you have to have a Lee FCD die to crimp a non-cannulure bullet. Just use the seating die to crimp very lightly.
But again, I would not ever crimp anyway for a bolt gun.

You want to FL size your hunting ammo to insure they will all chamber, and all chamber easily on follow-up shots.

Neck sized cases can run a little stiff, and cause problems when you least want to have problems on a hunt.

rc
 
I'd also advise against crimping.

Everytime I've tried that Lee FCD on my .308s (all semi-autos), I found my accuracy to be worse with the crimp than on identical loads that weren't crimped.

That might just be me, or maybe I need to develop a "feel" for the crimp die.......................but either way, it's a step that I can live without.
 
In sort of reverse order...

Full length resizing is recommended for hunting ammo because there is less chance of the round failing to fully chamber at a critical moment.

Crimping rifle ammo. You will probably get many, many opinions. There are two reasons for crimping bullets in the case:

One is to keep the bullet from being pushed deeper into the case from either the action itself or from recoil bouncing the rounds back and forth in the magazine.

Two is to keep the bullet in the case a trifle longer so the powder burns well. Slower powders especially need more - encouragement - to burn completely and uniformly.

You asked about crimping with the seating die. Die sets have been made that way for - ever. Most reloaders (me included) find seating and crimping in two operations gives better results. It's not forbidden to seat and crimp all at once, but it's better the other way. However, this involves another step in the process. Most bottle neck rounds are not belled to seat bullets, so one doesn't have to take the bell off, as in handgun rounds. With a proper neck tension (from proper sized resizing dies), a heavy crimp is not so important.

Sierra bullets (excellent bullets, by the way) think crimping is bad for rifle ammo. My own experience tends to show some ammunition is much better with a crimp and some does well without. Lee (who makes the Factory Crimp dies) thinks crimping is a great idea. I have several Factory Crimp Dies in various calibers and use them often. I like the results, over all. I do not crimp on my .22-250 as I don't load them in the magazine hardly ever and the recoil is pretty light.

There is the benefit of my august wisdom. Good luck.
 
Some do crimp for auto-loaders, but I'm not convinced that is necessary either.

I am. Only took once to shove the bullet back into the case on my ar. and I put a very slight crimp on all my .308's now. It got hung on the feed ramp just enough to push the bullet back into the case some.I spotted because the round didn't chamber and I ejected it.

Bolt guns no.
 
Try polishing the expander for a bit more neck tension. Thats what I do for the bullets without groove. Saves a step in the proccess.

peace.
unloaded
 
I never bother crimping bottleneck rifle rounds for use in a bolt rifle. But then again I don't shoot a .338 Lapua, .375 or .460 Weatherby Magnum either.

If neck tension alone isn't enough to hold a bullet secure in a .308win case, then something's not right.
 
If neck tension alone isn't enough to hold a bullet secure in a .308win case, then something's not right.

I would agree on a bolt gun but not on a semi auto.
 
+2

Neck tension alone in a .308 should take at least 60 - 70 pounds of force to move the bullet in the case.

I have to chuckle every time I read the old "push on it with your thumb and see if it moves" advice.
If neck tension is even half right, you will only hurt your thumb!

If you have an autoloader that feeds so poorly it is exceeding 70 pounds force on the bullet tip, you need to work on the rifle or magazine, not the load.

Many die sets come with an expander that is just too big for most case necks.
Reduce it down until you get the correct neck tension with the cases you are using and there is no need to crimp.

rc
 
Many die sets come with an expander that is just too big for most case necks.
Reduce it down until you get the correct neck tension with the cases you are using and there is no need to crimp.

+1. Or, better yet, with bushing dies simply go to a smaller bushing.

Don
 
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