AR15 CRIMP ???

[x_wrench]

I have reloaded thousands of rounds, But doing so for an AR15 is stressing me out. all of the bullets I have purchased for this gun have a cannelure in them. I have loaded some without, but they were ones purchased for a single shot (without a canalure), so the bullets moving was never an issue. I was crimping the bullets that I am firing in the AR with a light crimp with a Lee Factory Crimp die. the issue I'm having with the bullets with a canalure, is the canalure is not in the place where 2.250" (magazine length) happens to be. in order to crimp in the groove, I have to seat the (55 grain Hornady BTSP) in the neighborhood of 2.185". while that's easily accomplished, I'm not sure how that will effect accuracy. typically I have found that longer oal contributes to better accuracy. I am not the type of person to do mag dumps until every round is laying smoking in the dirt, and the gun barrel is smoking hot. I specifically purchased a heavy barrel target type of gun. as accuracy is king in my mind. but I wanted an ar15 rifle for a long time. so that is what I bought. do I NEED to crimp? if so do I forget about the canalure and continue doing a light crimp at 2.250 despite the canalure location? I know that I could load up a bunch of each, and go shooting. but with components so tough to find, I would like to get some input before doing a bunch of shooting to learn something I might get an answer to without firing a shot.

 

[entropy]

Your bullet choice was not optimal for your expected use. Try 77 gr. SMK's if you want accuracy, and seat them at 2.25" if it works for you.

 

[Blue68f100]

As long as you have good neck tension so the bullet does not move when chambering, your good without crimping. I run 0.003"-0.004" neck tension on my AR-15 blasting ammo and do not crimp. I do not crimp any of my rifle rounds. Neck tension is the key. Like you found out the cannalure is hardly in the place you need it to be.

 

[AJC1]

Neck tension is vastly superior to any crimp. Unless your using a tube mag. Polish down your expander ball a little and test....

 

[Artg56]

I’m loading the 55g Hornady FMJBT cases trimmed to 1.760 seating the bullet exactly at the cannelure midpoint for a finished length of 2.210

The 62g Hornady FMJBT is finishing at 2.230

Lee crimping die, very light crimp

The 62g over 22g of IMR 4064 is proving my more accurate round

I am not expanding my case mouth (0.004) and can just set the bt into the case, I’m sure I don’t have to crimp at all but am currently loading a batch of Sierra 55g SBT no cannelure to test

 

[EricBu]

The cannelure is not critical. You can seat to the length you prefer and crimp with the FCD and just ignore the cannelure, it won't impact anything other than bugging you when you look at it;-). If I'm not mistaken, the FCD for .223 is a collet type, and does not need a cannelure anyway. If you aren't belling (flaring) the brass, the crimp is optional anyway.

 

[Skeptic13]

Hornady makes a 60 gr spire point that does not have a cannelure. I have loaded it a lot without crimping and find it to be fairly accurate. With the 55 gr with the cannelure I always load it to the depth of the cannelure and then do a light crimp. You should at least try it both ways and see what kind of performance you are getting.

 

[x_wrench]

man, you guys are on the ball! thanks! i seldom crimp most of my rifle rounds, except 300 win mag Hunting rounds, and of course the lever guns. but being my first semi auto, I knew there would be some learning to do. thanks for the help.
"The 62g over 22g of IMR 4064 is proving my more accurate round"
I have never had any luck with IMR 4064. I ran it thru all of my rifles that I could find a load for it. and mediocre was as good as it got. except for denting the shoulders of every round I shot using it. but thanks for the input. I can not say I have tried that load. but I will not buy another bottle of that powder again.

 

[Varminterror]

If your AR feeds poorly so it crushes bullets back into the case, fix the problem - fix the feeding - don’t use a bandaid and crimp.

 

[Ifishsum]

I load and shoot a lot of .223 for the AR mainly for highpower/service rifle so our accuracy goals would be similar. What I've learned both on my own and from shared information from other competitors is that almost nobody bothers to crimp in any fashion. Most of us probably tried it at some point, if for no other reason than to learn for ourselves if it does or doesn't make a difference. Also, with many bullets seating depth just does not make a lot of difference in accuracy, just load to mag length and go - I don't see cannelured bullets on the line much but if so the cannelure would be generally ignored I am sure. As long as you can verify your bullet is not jammed into the lands at magazine length (and a few can be, like the 52/53gr Match King).

Most shooters use long single loaded bullets for 600+ yards, often seated close to the lands (but not always). I have come to believe that how the round is chambered can affect that seating depth in the other direction; most of us use a sled which makes it easy to just drop the round on top and hit the bolt release, which can make the bullet creep forward when the bolt slams to a close (with no resistance from a magazine) just like a kinetic bullet puller. Nobody is going to crimp a 40 cent Berger (and it probably wouldn't even help IMO) I just make sure the round is at least halfway started into the chamber before releasing the bolt. Some of those hybrids shoot much better at .030 or more away from the lands.

 

[Mark_Mark]

The cannelure is not critical. You can seat to the length you prefer and crimp with the FCD and just ignore the cannelure, it won't impact anything other than bugging you when you look at it;-). If I'm not mistaken, the FCD for .223 is a collet type, and does not need a cannelure anyway. If you aren't belling (flaring) the brass, the crimp is optional anyway.

so the dotted line is a suggestion not a rule!

My ADD won’t let me

 

[Charlie98]

I have that same issue with the 150grn Hornady FMJ… the cannelure is way too high, so I just seat to my length and ignore it, or I will use a light tap with a taper crimp die if I want some insurance (for blasting ammo.)

 

[AK Hunter]

I crimp all of my reloads for my semi auto but not for my bolt action guns.
I have seen way to many rounds in the dud buckets at our range with the bullet pushed back from shooters that reload & don't believe that crimp is needed. If they want to keep giving me brass, bullets & primers I'm all for it.
I don't pay any attention to the cannelure line, just load to the OAL depth & crimp. The crimp will create it's own cannelure in the sides of the bullet.

 

[DMW1116]

I intend to crimp but I keep forgetting. My last test batch I forgot to crimp and they shot fine. The only thing I don’t crimp are 308 rounds with 175 grain SMKs for my PA-10. I tried and the accuracy went all to pieces. I made a dummy round and ran it through the action a couple times and measured it. The COAL actually got longer by about 0.001” per cycle.

 

[Charlie98]

It took me a long time to trust neck tension…

 

[edwardware]

. . . do I NEED to crimp?

No.

And if it's accuracy you're interested in, you generally shouldn't. Achieve adequate neck tension, ~0.002"+ expansion on seating, and skip crimping. I aim for 0.003-4".

 

[Bfh_auto]

man, you guys are on the ball! thanks! i seldom crimp most of my rifle rounds, except 300 win mag Hunting rounds, and of course the lever guns. but being my first semi auto, I knew there would be some learning to do. thanks for the help.
"The 62g over 22g of IMR 4064 is proving my more accurate round"
I have never had any luck with IMR 4064. I ran it thru all of my rifles that I could find a load for it. and mediocre was as good as it got. except for denting the shoulders of every round I shot using it. but thanks for the input. I can not say I have tried that load. but I will not buy another bottle of that powder again.

I to load IMR 4064 in 223. But it's because it is the powder that would push 77s to 2680 in my AR with
If you see h4895, 8208xbr, or AR Comp.

so the dotted line is a suggestion not a rule!

My ADD won’t let me

I found the cannelure in .224 bullets usually worked well in my AR. I just started using it without crimping.

 

[cfullgraf]

I do not crimp any of my AR-15 ammunition and that includes 17 Remington, 204 Ruger, 223 Remington, 22 Nosler, 6x45, 6.5 Grendel, 6.8 SPC, and 300 Blackout.

Also, no crimps on my M1 (30-06) and M1A (308 Win) ammunition.

I make sure I have adequate neck tension for then task.

M1 Carbine gets a taper crimp primarily to remove any flare from the loading process.

Bolt action rifles do not get any crimp either but I do not have any shoulder busting rounds (something like 458 Winchester) that might dislodge a bullet from a round in the magazine that gets jostled by the rifle's recoil.

Tubular magazine rifles generally get a crimp. All of mine are pistol cartridge carbines which generally get a roll crimp anyway. I'm sure if I had any bottleneck cartridges used in a tubular magazine rifle, I'd probably add a crimp to them as well.

 

[Varminterror]

I have seen way to many rounds in the dud buckets at our range with the bullet pushed back from shooters that…own AR’s which don’t feed worth a damn and don’t realize they should fix it.

Fixed it for you.

 

[rdnktrkr]

I also have measured unfired rounds after chambering in my ARs and have noticed a slight lengthening (I don't know if it was enough to affect accuracy or safety), I didn't notice this with factory ammo, therefore I put a light crimp on my semiautomatic rifle rounds, for my bolt actions I depend on neck tension. I bought some 62gr sp bullets and found they were more accurate loaded longer than the cannelure, so I loaded them to mag length and called them GTG, now I don't look for 224 bullets with a cannelure.