30-06 COAL issue/question

[Michael in California]

Thanks J-Cat.

Unfortunately, its too wet to go shooting, so it will be next week at the earliest before I get results. I might be putting a clutch in my car next weekend, ending other activities.

I guess I'll just look at the shiny brass all week.

[maxx03]

Measuring coal at the ogive is the way to go, especially on spitzer type bullets.

[milotrain]

I've pulled bullets that were crimped, the jacket is absolutely deformed in all cases (some more, some less, Lee FCD, and Dillon crimp die). I don't suspect it would be detrimental to accuracy but with a thin jacket like the Amax or J4 I wouldn't risk it. Like everything with reloading for accuracy you try to reduce variables to maximize consistency. I wouldn't crimp even if I suspected that my crimp was uniformly deforming bullets.

I've shot hundreds of 69 grain Nosler Custom Competition HPBT through 2 AR-15s.

You may not know but 790 has the ugly bear trophy for service rifle, a distinguished badge, and a P100 tab. That doesn't mean he's always right but you wouldn't go far wrong just doing everything he tells you to.

[Grunt81]

I'm not familiar with that award or the competitions in which it's earned, but I love the M-16 platform. Thankfully, it's hell of a lot more inherently accurate than an AK-47. A head shot from the standing position at 200 yards with iron sights is not hard at all, from experienced hands. A high magnification optic makes 600 yard shots no problem at all with a .223 from an AR-15.....But still, no semi-automatic, mass issued service rifle was designed to be a precision weapon. They are designed to be combat weapons where reliability reigns supreme. Some people might call a head shot precision, but to me, precision is an eyeball shot at 200 yards.

The violent action of the bolt jamming into the buffer spring, scooping up a new round from the magazine, then slamming into the chamber faster than you can blink, imparts a lot of inertia on the bullet from the sudden stop. Without a crimp, your banking on neck tension alone to overcome this inertia and maintain the bullet in the neck. If it doesn't, then you'll end up with a bullet stuck in the lands and a chamber full of powder.

Good for him if it's been working out, but I'd urge you to measure an uncrimpt round and put it second from the top of the magazine, fire the first shot, eject the second round, and measure again to see if it grew at all. The crimp, regardless of the line it leaves in the jacket, ensures head space is the same for each round after the violence of cycling .

If the OP is loading for a bolt action, I don't see a need to crimp at all, whether there's a cannelure or not. Chambering a round in a bolt action is a relatively delicate operation compared to the above. Neck tension alone, is fine.

[milotrain]

I'm not familiar with that award or the competitions in which it's earned, but I love the M-16 platform.

• Ugly Bear, is the California State trophy. He won it in service rifle across the course. (Irons at 200,300,600)
• Distinguished marksman
• P100

Good for him if it's been working out, but I'd urge you to measure an uncrimpt round and put it second from the top of the magazine, fire the first shot, eject the second round, and measure again to see if it grew at all. The crimp, regardless of the line it leaves in the jacket, ensures head space is the same for each round after the violence of cycling .

Don't have to. I've done it, it's not a problem, even in a rapid fire stage. Proper neck tension does the same thing.

If it doesn't, then you'll end up with a bullet stuck in the lands and a chamber full of powder.

No reasonable AR(556) load should become unreasonable transitioning from jump to jam. If you are running loads that close to the edge then I'd question why. Even the crazy guys who run hot loads don't see a problem jamming them. I ran a hot load for a wylde chamber in jump, moved it to a tight .223 match chamber in jam and the only difference was cratering on the primer. If your neck tension is such that bullet moves enough under recoil to move in the case neck then it's not swaging itself into the lands as much as it's just slipping back in the case. That's not a good situation to be in, but proper neck tension is an important part of reloading. I know a few excellent shooters who crimp their 556 match loads, and they do fine with them but I strongly suspect that this is a personal choice thing, and not any kind of problem either way.