.223 for AR - Crimp or no crimp?

[EddieCoyle]

I was wondering what everybody does. I'm about to load some .223 for my Bushmaster AR with 55gr Hornady FMJBT bullets with a cannelure.

I picked up a Lee collet-type crimp die to try out. I intend to load a few of each and then chrono and test for accuracy.

My question is:

Do you guys crimp your rounds or not? Do you notice a difference between crimped and uncrimped reloads??

 

[doobie]

I was told not to crimp rifle by the person who showed me the basics... I don't recall his reasoning.

 

[bpm990d]

I've read that in some applications that crimping can improve accuracy slightly. I think this article has some interesting things in it.

I however do not crimp and probably will not ever. I can change the neck tension with a bushing die if I think it needs more. I'd never consider it on a match bullet without a cannelure though.

B

 

[Adam_MA]

For an auto loader, and plinking rounds I crimp. I don't crimp the rounds that I load for accuracy out of a bolt action, but I do crimp hunting loads.

My reason for this is simple. I loaded up a couple of rounds measured and recorded the exact COL and did not crimp. I put them into the mag, and let the bolt fly to chamber the round. I then checked the COL of the round in the chamber, and the others in the magazine. The round in the chamber had set back noticeably, the second round in the mag had set back slightly, and the third round in the mag was the same. I then chambered the second round that had already been set back slightly, and checked. The COL had changed again, and the bullet had set back even more than the first round, but to a greater margin than the first slight set back, plus the chambering set back of the first round added up.

My conclusion was to crimp auto rounds.

 

[PatMcD]

For an auto loader, and plinking rounds I crimp. I don't crimp the rounds that I load for accuracy out of a bolt action, but I do crimp hunting loads.

My reason for this is simple. I loaded up a couple of rounds measured and recorded the exact COL and did not crimp. I put them into the mag, and let the bolt fly to chamber the round. I then checked the COL of the round in the chamber, and the others in the magazine. The round in the chamber had set back noticeably, the second round in the mag had set back slightly, and the third round in the mag was the same. I then chambered the second round that had already been set back slightly, and checked. The COL had changed again, and the bullet had set back even more than the first round, but to a greater margin than the first slight set back, plus the chambering set back of the first round added up.

My conclusion was to crimp auto rounds.

If simply chambering a round in your rifle (assuming we are talking about an AR here?) sets the bullet back in the case, something isn't right here.

Assuming .223 loaded to mag length with no crimp:
You should be able to take one of your rounds, and push the tip against something hard and immovable (with a moderate amount of force) and not move that bullet in the case. If you can, I think the expander button in your sizing die might be too big or something, resulting in a loose fit.
If the loaded rounds are fine, I would check that chamber/throat before firing another round. I can't imagine the throat would be short-chambered enough that it would effect a mag-length round, but stranger things have left factories before.


I don't crimp.

 

[Lugnut]

I just started the same set up. I don't crimp because there is no belling to remove... and it seemed like most folks don't crimp.

 

[EddieCoyle]

I just started the same set up. I don't crimp because there is no belling to remove... and it seemed like most folks don't crimp.

I was asking because my bullets have a cannelure. Why put one in if there's no need to crimp? I'm going to try it both ways and see what happens.

 

[xstickfightx]

I personally crimp my .223 reloads using the Lee collet die. These are being shot out of my Ar15.

 

[RKG]

I have never crimpled .223.

 

[Lugnut]

I was asking because my bullets have a cannelure. Why put one in if there's no need to crimp? I'm going to try it both ways and see what happens.

I'm no expert but I assume it's there if you want to crimp. I just don't. My bullets have the same cannelure. I'd also assume that unless you were very precise about keeping your cartridges trimmed to the same length- it would be a challenge to get a good consistent crimp. 1.750" is my trim length but they can go up to 1.760" before needing to be trimmed again according to my Speers manual.

 

[EddieCoyle]

I'm no expert but I assume it's there if you want to crimp. I just don't. My bullets have the same cannelure. I'd also assume that unless you were very precise about keeping your cartridges trimmed to the same length- it would be a challenge to get a good consistent crimp. 1.750" is my trim length but they can go up to 1.760" before needing to be trimmed again according to my Speers manual.

I trimmed all of my cases to 1.740. I'm using the RCBS small base X-dies. They instruct you to trim the cases .020" short of max length, then you never have to trim again.

 

[Lugnut]

I trimmed all of my cases to 1.740. I'm using the RCBS small base X-dies. They instruct you to trim the cases .020" short of max length, then you never have to trim again.

I have heard nothing but great things about those dies. Please let me know how they work for you as... well... trimming just plain sucks.

 

[bpm990d]

your going to squeeze the crap out of your cases with a small base die and won't get that many reloads out of them. Make sure to use a regular die or X die for subsequent loads.

B

 

[Gammon]

I have read that you should only crimp when using bullets with a cannelure which give the brass somewhere to go. Crimping on bullets without a cannelure may deform the bullet.

 

[Adam_MA]

I have read that you should only crimp when using bullets with a cannelure which give the brass somewhere to go. Crimping on bullets without a cannelure may deform the bullet.

Not true. The Lee FCD will actually add the cannelure to the bullet while crimping. Says it in the instructions, and I tried it to see if it were true.

 

[Cledus J. Crabb]

If simply chambering a round in your rifle (assuming we are talking about an AR here?) sets the bullet back in the case, something isn't right here.

Assuming .223 loaded to mag length with no crimp:
You should be able to take one of your rounds, and push the tip against something hard and immovable (with a moderate amount of force) and not move that bullet in the case. If you can, I think the expander button in your sizing die might be too big or something, resulting in a loose fit.
If the loaded rounds are fine, I would check that chamber/throat before firing another round. I can't imagine the throat would be short-chambered enough that it would effect a mag-length round, but stranger things have left factories before.


I don't crimp.

I've put thousands of rounds thru my AR and never crimped. Never used a bullet w/ a cannelure. With the effort it takes to pull a bullet from the case, using either a inertia hammer or press mounted puller, I can't imagine a bullet ever moving thru normal handling or cycling through a magazine.

 

[GTOShootr]

I buy into the not crimping thinking too. I couldn't push my non-crimped bullets in when I tried with force. However, on the rounds with the cannelure (Hornady) that had a space between the brass and bullet at the cannelure, I used the Dillon taper crimp die to lightly close it (that's all I ever use the crimp die for). Some other rounds (Winchester), I seated to right below the cannelure and was still under mag length and left it. I still learning the rifle stuff.

 

[EddieCoyle]

With the effort it takes to pull a bullet from the case, using either a inertia hammer or press mounted puller, I can't imagine a bullet ever moving thru normal handling or cycling through a magazine.

Exactly what I found when I pulled a couple last night. I can get crimped .500 S&W Mag bullets out easier.

However, on the rounds with the cannelure (Hornady) that had a space between the brass and bullet at the cannelure, I used the Dillon taper crimp die to lightly close it..

This was my thinking too (I should probably "close the gap"). I loaded up 100 rounds last night and lightly crimped half of them with a Lee collet type crimp die. I'm going out in about an hour to try out each type. I'll post back later on with the results.

 

[Cledus J. Crabb]

I'd be curious to see how you make out, accuracy wise.

 

[EddieCoyle]

OK. Here's the results - The crimped rounds seemed to be slightly more accurate than the uncrimped rounds. The difference was slight, so it could have been shooter error.

I shot my Bushmaster A2M4 with a C-More 4moa 1X red dot sight. The red dot was sighted in so that the S&B factory ammo that I had been shooting hit to point-of-aim at 100 yards.

Today, at 50 yards, there was no discernible difference in 5-shot group size - they were both about 2-1/2", and 4" below point-of-aim. At 100 yards, the crimped rounds' 20-shot group was about 5", and 2" below point-of-aim. The uncrimped rounds group was a little over 6", and 4" below point-of-aim.

The battery in my chrono turned out to be dead so I don't have any velocity info. I was shooting 55gr Hornady FMJBT w/Cannelure over 24 grains of H335.

 

[Adam_MA]

Thanks for the report.

As for my, I will continue to crimp, as I strive to mimic milsurp ammo. I have a ton of milsurp ammo that I don't want to shoot, but love the way it works through my rifles, thus I want to be as close to that as possible.

 

[Finalygotabeltfed]

I always crimp rifle ammo unless the bullet doesn't have a cannelure and those are only for bolt gun use here.
I load to mil spec or just short of it and put a slight taper crimp using the Dillon crimp die. No problems with accuracy. Billions of military rounds can't be wrong.

 

[Lugnut]

That's the exact same starting load I used. I have a batch made at 24.5 gr I'm going to test later. Are you staying at 24gr? I had no problem with the 24gr load but wanted to get somewhere in the middle range as recommended for that bullet.

The battery in my chrono turned out to be dead so I don't have any velocity info. I was shooting 55gr Hornady FMJBT w/Cannelure over 24 grains of H335.

 

[EddieCoyle]

That's the exact same starting load I used. I have a batch made at 24.5 gr I'm going to test later. Are you staying at 24gr? I had no problem with the 24gr load but wanted to get somewhere in the middle range as recommended for that bullet.

That's actually above max (23.6 I think) for that bullet per the Hornady Manual.

 

[Lugnut]

That's actually above max (23.6 I think) for that bullet per the Hornady Manual.

Strange. I'll have to check my manuals again when I get home ( I have Hornady 13? and Lyman relaoding manuals) and I'd swear that Hornady had the same 55gr bullet with a starting range of 24.0 and a max of 26.0gr!


EDIT: Here' some of the data I used- this is what I have in my spreadsheet:

223 Rem Hornady FMJ-BT H335 WSR 2.215" 24.0 Shot 5 rounds… no issues at all. Range for this is 24-26gr.

 

[Steve_P]

That's actually above max (23.6 I think) for that bullet per the Hornady Manual.

At what OAL is that charge specified at?

 

[EddieCoyle]

Strange. I'll have to check my manuals again when I get home ( I have Hornady 13? and Lyman relaoding manuals) and I'd swear that Hornady had the same 55gr bullet with a starting range of 24.0 and a max of 26.0gr!

I think that's what the Speer manual had (plus they want you to use a magnum primer). I'm pretty sure Hornady was a lot lower.

The Lee is somewhere near the Speer, and the Hodgdon website only gives ~1060 fps handgun powder loads for that bullet! (They give higher ones using rifle powders for the Speer 55gr though).

I wonder if that is due to the fact that the bullet has exposed lead on the base.

At what OAL is that charge specified at?

C.O.A.L. = 2.200"

 

[Steve_P]

Ok, thanks. I am starting to load 223.
I started at 24.3gr or H335, 2.210 OAL with the same Hornady 55gr. Haven't had a chance to test the loads out yet, though.

Glad to know there are others out there doing the same.
Steve

 

[EddieCoyle]

Ok, thanks. I am starting to load 223.
I started at 24.3gr or H335, 2.210 OAL with the same Hornady 55gr. Haven't had a chance to test the loads out yet, though.

Glad to know there are others out there doing the same.
Steve

All of the manuals recommend a 2.200" C.O.A.L. for this bullet, but I don't see how this is attainable with standard length (1.750") cases. I trimmed mine to 1.740" per the instructions that came with my RCBS X dies and the top of the case ended up at the very top of the cannelure when I loaded them to 2.200".

 

[Steve_P]

I noticed the same. I am also using the x-die.