Home Forums Hunting & Shooting AR and Tactical Rifles Crimping

How many crimp their bullets when reloading? I realize there's not much recoil ... just curious.

Never have. Run neck tension as needed plus mostly 100% case volume charges...

YMMV.

Though I"ve only probably gone through around 200,000 rounds give or take in the ARs.

I use the Lee crimp die cause its cheap insurance and doesn't hurt a thing.

Rost, what powder are you running that fills 100% case capacity?

Ditto. I've also used the Dillon taper crimp die.

Me too

Varget, N540 typically do with what I shoot. I don't recall RE RL15 but it seemed close for loads with 75 bthp seated to mag depth of 2.240 oal.

Mind you I may not have been full 100 percent but pretty close.

I"ve run probably 5000 give or take, 75s with TAC and no crimp and shot them in combat matches and never had an issue. I dont' think that was near 100%.

I do IE did when I was still shooting, run moly so that ups your powder charge a bit. FWIW

One of the questions never posed on this subject, many do it just because, but of those, how many have run many thousands of rounds uncrimped vs crimped and ever ran into a problem?

I don't like work hardening my brass any more than I Have to, to start with. And though I've not done any testing, if crimps were to have zero effect on accuracy each shell casing would have to be trimmed to the same exact length each time to get the same release tension from shot to shot.

If I were shooting BR, then I could see it. But not the number of rounds we shot... often give or take 20,000 a year in the later years.

No proof mind you. But then I use the same theory y'all do on it doesn't hurt but I am not sure if I need it.... BR shooters don't crimp, and I"m after accuracy....

I hope my last comment.... brain is running on for some reason...

Those that crimp for ammo thats for SHTF kind of thing, IMHO, if you are not also sealing the primer and the bullet, then you are not doing all you need to.
I'd much rather deal with a setback bullet and a jam, than have powder or primer compromised when I would need it the most.

FWIW I have a bunch of 69 bthp, and 75 bthps loaded up no crimp or sealant and I'd personally risk my life on them performing as is if ever needed.

As I said in another thread, I had 2 357 Sig bullets setback in a Glock but have never had one in an AR.

We have seen accuracy tests posted here where crimped ammo was more accurate. I saw standard deviation go down in my own loads, though that doesn't always equal better accuracy.

It's all about neck tension no matter how you get it.

Neck tension no doubt.

I can't comment on the accuracy with crimped, as noted I've never crimped a 223 round. I've never needed more accuracy than I was already getting.
Though that is kinda a dumb statement but .5 moa or less sufficed.

And I still lean back to the fact if crimps were needed for accuracy, BR shooters would, as a whole.

Wouldn't bother me to shoot crimped ammo or to have to crimp mine though. Just never have crimped any other than revolver loads and taper crimp the ACP..

I know this is correct using a taper crimp die. I've read that is not the case with the Lee FCD, I dunno.

The trim issue is another reason to have a 650 or 1050 toolhead setup with a Dillon carbide size die, a Dillon power trimmer, and a Lyman 22cal M die. This eliminates that worry, 'cause it IS trimmed everytime.

I have run thousands of both. For my 77 gr match loads, I do not, and have never had a problem. For my 55 gr "whatever" loads, I do. Accuracy is apples and oranges, since I take a lot more care in my match loads in other areas than my whatever loads, so I cannot compare the two. As for the Lee FCD, I do not bother trimming those until loads 3-4, since trim length is not critical with them.

The only cartridges I crimp are those used in tubular magazine rifles.

I've got a brand new Lee FCD in .375 H&H. I've never used it in over 600 rounds because I found I didn't need it.

If I need more neck tension, I polish the neck expander ball down a couple of thousands.

Bullet setback, so it doesn't blow up in your face.

Though I haven't run nearly as many rounds through AR's as rost495, I've still run a pile through various AR's without a problem--and never crimped one.

I"ve asked folks to explain, HOW can case length not be critical with a FCD? The longer cases run further into the crimp die, and as a result HAVE to crimp with more pressure? How can a steel fixed die compensate for varying case lengths?

IT may well because I"m not an engineer, but no one has ever been able to explain to me how.

Just like the die that sizes without allowing case growth... it has to push that brass back somewhere, so even if it isn't allowing growth, its not allowing it by pushing it back hence it did grow, and growth equals work hardening and or eventual case seperation.

And how long have you been reloading?

I jumped out of airplanes for 20yrs, something short of 200 jumps. I have a friend who has probably made that many freefalls while too drunk to drive, often without an altimeter. He's still alive.

An AR doesn't have an escape path for gas like a modern bolt-action. It just blows the [bleep] up, usually out the right side of the upper. There is one such upper laying on a table where I work now. We had eight of them grenade all the same time last year, though that was from a bad lot of ammo.

Don't drive like Jeff Gordon...unless you can. I'll crimp my loads.

He has been reloading longer than I, I'd bet.

But the AR is something my wife and I almost slept with for around 15 years straight, as noted up to 20,000 rounds or even more a year depending.

I"ve never seen an AR blow up yet. Doesn't mean they dont. But to say they will when you admit the 8 you reference were from bad ammo, doesn't tell me much.

If you think that controlling neck tension and loading close to 100% density doesn't prevent things, then I offer, how long have you been reloading? And what quality of ARs are you working with?

Me.... I haven't reloaded very long actually. IIRC I started around 1976.

And I"ve been around a LOT of ARs fired in matches, has to be millions of rounds... especially when you have 250 firing points at Perry, and up to 7 relays shooting on a given day at times... not to mention that we shot almost every weekend, and sometimes twice... and I doubt that I"ve ever shot an 88 shot match that had less than 15 competitors in it....
I still have not seen an AR blown up.

But it could be because of the quality of the guns, the knowledge of the reloaders. And knowing what I do, I'd venture a guess that probably 10% of that ammo was crimped.

I can say though, on your side, that I don't really see what a crimp can hurt, unless you are after the last accuracy.

But to me they are just like weighted bolt carriers. If you build the gun right, you use a standard carrier. If you don't, you have to put a bandaid(weight) in there.

Much the same as my opinion of crimps.

My point Rost is that you and MD are proven commodities as reloaders and shooters. Most shooters are not. I'll wager close to a million dudes are gearing up to reload, as we speak, most of 'em for an AR. A few read our rants. Advising not to crimp is akin to my drunken skydiver buddy saying that altimeters are optional.

I am a drunken sky diver and I crimp my loads!

Jeff, I never crimp a barnes bullet but I do crimp traditional bullets. All my cases are trimmed to length. Interesting to me is that it does not seem to effect my accuracy, but I don't shoot at 600 yards.