Do you recommend crimping the neck on AR15 loads? [Archive] - Glock Talk

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RMTactical
08-25-2012, 18:10
specifically .223.

F106 Fan
08-25-2012, 19:49
If the bullet has a cannelure, sure! If it doesn't, there is no need to crimp as long as the resized brass provides adequate neck tension. I think you will find that most reloaders don't crimp .223 if the bullet doesn't have a cannelure.

We just discussed this a few weeks ago. Perhaps the forum search feature will turn up the thread.

Here's one of the threads:
http://glocktalk.com/forums/showthread.php?t=1364087&highlight=.223+crimp

Be aware that this has been debated endlessly with no real resolution. Some reloaders always crimp, some never crimp and some just crimp bullets with a cannelure.

Richard

PCJim
08-25-2012, 20:57
I'm with F106 on the issue. If there's a cannelure, crimp it. If there isn't, don't.

fredj338
08-25-2012, 21:41
I'm with F106 on the issue. If there's a cannelure, crimp it. If there isn't, don't.
Pretty much how I roll em too. A cannelure bullet gets a mild roll crimp, anything else, nope.

TX Archer
08-25-2012, 22:51
Pretty much how I roll em too. A cannelure bullet gets a mild roll crimp, anything else, nope.
Just curious, Fred. I've recently begun loading .223. Can you quantify a "mild crimp"?

steve4102
08-26-2012, 06:45
I crimp all my semi-auto handloads with the Lee Factory Crimp Die. It helps secure the bullet and increases accuracy. It works on bullets with or without a cannelure.

squirreld
08-26-2012, 07:57
I crimp all my semi-auto handloads with the Lee Factory Crimp Die. It helps secure the bullet and increases accuracy. It works on bullets with or without a cannelure.

Oh no you didn't...........

steve4102
08-26-2012, 08:03
Oh no you didn't...........

I didn't?

Zombie Steve
08-26-2012, 08:29
I generally don't crimp .223 loads for the AR.

If you're going to do it, just barely touch the darn thing. It's really easy to squash the shoulder.

The AR's action tends to yank bullets out a few thousandths when it comes to an abrupt stop in the chamber. If you find yourself re-chambering a round over and over, a light crimp might be a good idea.

F106 Fan
08-26-2012, 08:47
Just curious, Fred. I've recently begun loading .223. Can you quantify a "mild crimp"?

I don't know how Fred is crimping them but my process is pretty simple. First, when I set the bullet at some nominal OAL, the leading edge of the case mouth is almost exactly at the forward edge of the cannelure. I use the Lee FCD to roll a crimp that just barely depresses the case mouth into the cannelure. It is certainly not bottomed out. In fact, I measure about 0.005" change in diameter.

The rifle version of the Lee FCD seems to work pretty well as a crimping die. All of the cases are trimmed during case prep so it is pretty easy to get a uniform crimp.

For no particularly good reason, I set my dies up to reproduce the crimp on the Wally World Federal .223 bulk ammo. Federal is also using a 55 gr bullet with a cannelure so it seemed reasonable to duplicate what they were doing.

I wasn't overly concerned with the bullet moving forward during chambering but I was worried about it setting back from either chambering or recoil. With the forward edge of the case mouth touching the leading edge of the cannelure, setback should be controlled.

The nature of my shooting is that when a round is chambered, it will be going down range. I don't think there is much chance of multiple chamberings.

I also figured that there must be a reason that Montana Gold put the cannelure at that specific location on the bullet. So, I used it.

Richard

Zombie Steve
08-26-2012, 09:26
I'd say see if you can get away with no crimp first. No need to make things more complicated if they don't need to be.

Hoser
08-26-2012, 12:53
As long as your brass is the same length, knock yourself out.

If it is a different length, you will end up with more crimp on some and less on others.

That said, I don't crimp any rifle ammo.

ColoCG
08-26-2012, 13:26
I agree with Hoser. With a few exceptions on ammo for dangerous game, I don't crimp any rifle rounds including .223's for a couple of AR's.

klmmicro
08-26-2012, 13:33
I used to, but after loading some match ammo with a friend I decided to skip the step. I did not find any ill effect from a lack of crimp at all. Course, did not see any great improvement either...

freakshow10mm
08-26-2012, 22:17
I recommend proper bullet tension. There are two methods: crimping into a cannelure and properly sizing. Both work. I prefer properly sizing to control the bullet tension.

F106 Fan
08-27-2012, 06:17
I used to, but after loading some match ammo with a friend I decided to skip the step. I did not find any ill effect from a lack of crimp at all. Course, did not see any great improvement either...

Did you take the opportunity to measure the change in OAL of, say, the 30th round in a magazine to see if any of the bullets set back from recoil? It would also be worth ejecting the last round after chambering and checking the OAL.

I haven't done any of these measurements but perhaps the next time I am out I will do so. Of course since my rounds are lightly crimped into the cannelure. I don't expect any changes. I might see the OAL get a little longer from chambering but setback shouldn't be a problem.

With my original SP1 and an 8 to 10# inconsistent trigger, I don't expect much better than 1-1/2" at 100 yards. I'm not sure better grouping is even worth trying.

Richard

Boxerglocker
08-27-2012, 07:32
Oh no you didn't...........

Yes, yes... he did :upeyes:

I crimp all my target / match 55g stuff. Either Horandy or MG FMJs W/C. I FL size and trim all my brass each and every time though. XL650 with a RT12000B trimmer.

F106 Fan
08-27-2012, 08:53
Yes, yes... he did :upeyes:

I crimp all my target / match 55g stuff. Either Horandy or MG FMJs W/C. I FL size and trim all my brass each and every time though. XL650 with a RT12000B trimmer.

And I copied what you are doing; thanks for the suggestions. The trimmer on a 650 toolhead makes short work out of getting a uniform case length.

With the Federal brass I am using, very little material is actually removed. In some cases, the mark at the case mouth is only part way around. All I am doing is squaring up the case.

Richard