Crimping for Accuracy

[Bigahh]

Would like some expert opinions about crimping. I recently purchased a used Remmy 700 Mountain Rifle in 30-06. It has the little skinny barrel that I hate, but I could not pass up a good deal, and plan on adding a new barrel in the future. I found out this week the rifle shoots wonderful with any load that has a slight crimp from a lee Factory crimp Die crimped on the cannelure. Shooting the same load and not crimping seems to open up the groups by a large margin. I am using all Hornady Bullets at my range session. The question I have is....Can I or should I crimp a bullet that does not have a Cannelure? A good example would be a Nosler Bullet. Is crimping effective on a Bullet like this ? I could never get decent accuracy out of Noslers Like I can with a Hornady, and I believe now it is due to crimping. I tested this out on my BLR today also. I loaded up 5 shells each with and without crimping, and crimping on the Cannelure made my groups much tighter. Just under an inch with crimping to almost 2 inches with no crimp. It must be something to do with initial pressures.

[iceman]

I have crimped bullets out of the crimp groove with the Lee FCD and have had no ill effects. I have pulled and looked at the bullets and there is a small indentation in the jacket. I have never tested with or without crimp because I usually always crimp when I can. Give it a try and let us know.

[Tycer]

Yes, the FCD does crimp well on non cannelured or on bullets where the OAL does not use the factory cannelure.

[J Miller]

I have never crimped bullets w/o a crimp grove in any bolt rifle. Never seen the need. But I do have a very tight neck tension on the bullets.

For lever guns or military bolt guns where the bullets do have a crimp grove and are battered by the magazines I do crimp them.

From what I remember I didn't have that much accuracy variation either.

Joe

[jlchucker]

I always crimp everything I load with the Lee FCD, even those bullets without a cannelure. For bullets (and boolits) used in my leverguns, all have a crimp groove that I use, and these get a moderate, noticeable crimp. If I'm crimping calibers that I use in bolt action rifles, I normally set my crimp die to just "bump" them a little. My thinking here is that it might equalize case tension all the way around the bullet at the case mouth. I don't crimp such ammo really hard enough to create a crimp groove, just to equalize tension. I've not tested this formally, but bullets crimped this way do tend to group well. This has been my own notion--not something I've read about and tried.