Most Secure Crimp for .223

Fiddler 5.56 · March 24, 2007, 04:54 PM

I assembled a handful of Dummy rounds, with the sole intention, of trying to destroy them , with a "worst case scenerio" failure to feed/ Rifle malfunction.

The reason : Observation of a friends AR15, not ejecting and the follow up xm193 Federal round having the bullet pushed back into it's case.

In this case, I don't see how that particular round could have posed a problem as the Rifle had to be cleared and the round condition observed.---But--you never know.

So far, I can push , against a hard surface, all the bullets crimped with the LEE Factory crimp die----IF they have a canalure and they move . Those without a canalure, I cannot push back.
Slamming a round from a magazine into the back of a chambered round (DUMMY ROUNDS), as expected, pushes the bullet in and the case mouth deforms around the circumference of the crimp line.

Roll Crimp : Cannot push back against a hard surface but it does push back when a round is slammed into the back of it. Case could probably be resized and reused, unlike the LEE crimped one, which essentially collapsed around it's circumference.
What I'm doing is possibly meaningless in the real world and I really do not want to roll crimp. How tight, I wonder must I squeeze on the Lee die to make it hold.

Or, am I just being a little to Paranoid or Anal , about the crimping thing.
Appreciate your views.

swmike · March 24, 2007, 05:13 PM

You can take the best crimped round and destroy it if you try hard enough. In reality, using a LEE FCD die, crimping to the max (when the three slits in the collet are totally closed, just closed and no more) you have as good a crimp as you need for an autoloader. If the mouth of the case is crimped into the cannelure that's enough. If no cannelure, crimp enough cause the case mouth to press into to jacket.

Then go shoot.

Fiddler 5.56 · March 24, 2007, 07:41 PM

Yes, good point, most things can destroyed.
Only had exposure to the Lee crimp die for a few weeks so I need to build myself more ammo and more confidence I suppose. As you say, then go shoot !

Abstract · March 24, 2007, 08:04 PM

Quote:

What I'm doing is possibly meaningless in the real world

Yep, totally worthless!

Edward429451 · March 29, 2007, 06:19 PM

A lot of guys don't crimp for AR's at all and say no problemo. Ruger Mini-14's sre supposed to be crimped for. I settled on a light crimp and use them interchangably for both rifles.

Overcrimping should be your concern I think. I've heard those horror stories too. I only use a 1/4 turn crimp and have had no problems. I used two pc's of 2X4 to check mine on a bathroom scale before I got the feel for the crimps on 5.56. Drilled a small hole in one that fit the base of a round and put the other one on the wood on the scale and went point down to 30, then 50 LBS and rechecked for OAL until I was satisfied .

Tim R · March 30, 2007, 07:28 PM

Repeated chambering with a autoloader is going to set the bullet back no matter how good your cimp is at some point in time. I would recommend getting action proving rounds availble from Brownells. These are dummies made for the task you require.

Now. If a guy knows at some point the bullet will set back, I would replace the home made ones when required.

Another thing to think about is you can add too much crimp and it will expand the neck making the bullet looser than tighter, if it will chamber at all.

RERICK · March 30, 2007, 08:12 PM

I've been using a Lee FDC for on all my AR rounds and have had no problems to date. Are you loading bullets that have a cannelure ?

March 24, 2007, 04:54 PM	#1
Fiddler 5.56 Member Join Date: March 5, 2007 Posts: 27	Most Secure Crimp for .223 I assembled a handful of Dummy rounds, with the sole intention, of trying to destroy them , with a "worst case scenerio" failure to feed/ Rifle malfunction. The reason : Observation of a friends AR15, not ejecting and the follow up xm193 Federal round having the bullet pushed back into it's case. In this case, I don't see how that particular round could have posed a problem as the Rifle had to be cleared and the round condition observed.---But--you never know. So far, I can push , against a hard surface, all the bullets crimped with the LEE Factory crimp die----IF they have a canalure and they move . Those without a canalure, I cannot push back. Slamming a round from a magazine into the back of a chambered round (DUMMY ROUNDS), as expected, pushes the bullet in and the case mouth deforms around the circumference of the crimp line. Roll Crimp : Cannot push back against a hard surface but it does push back when a round is slammed into the back of it. Case could probably be resized and reused, unlike the LEE crimped one, which essentially collapsed around it's circumference. What I'm doing is possibly meaningless in the real world and I really do not want to roll crimp. How tight, I wonder must I squeeze on the Lee die to make it hold. Or, am I just being a little to Paranoid or Anal , about the crimping thing. Appreciate your views.

March 24, 2007, 05:13 PM	#2
swmike Senior Member Join Date: June 25, 2005 Location: Marysville, WA Posts: 670	You can take the best crimped round and destroy it if you try hard enough. In reality, using a LEE FCD die, crimping to the max (when the three slits in the collet are totally closed, just closed and no more) you have as good a crimp as you need for an autoloader. If the mouth of the case is crimped into the cannelure that's enough. If no cannelure, crimp enough cause the case mouth to press into to jacket. Then go shoot. __________________ My definition of Gun Control--- A steady grip and hitting your target. "In God we trust, all others are suspects." "If I shoot all the ammo I am carrying, either I won't need any more, or more won't be of any help". ____________________________________________

March 30, 2007, 07:28 PM	#6
Tim R Senior Member Join Date: November 30, 2004 Location: God's side of Washington State Posts: 1,601	Repeated chambering with a autoloader is going to set the bullet back no matter how good your cimp is at some point in time. I would recommend getting action proving rounds availble from Brownells. These are dummies made for the task you require. Now. If a guy knows at some point the bullet will set back, I would replace the home made ones when required. Another thing to think about is you can add too much crimp and it will expand the neck making the bullet looser than tighter, if it will chamber at all. __________________ God Bless our Troops especially our Snipers.

March 24, 2007, 07:41 PM	#3
Fiddler 5.56 Member Join Date: March 5, 2007 Posts: 27	Yes, good point, most things can destroyed. Only had exposure to the Lee crimp die for a few weeks so I need to build myself more ammo and more confidence I suppose. As you say, then go shoot !

March 29, 2007, 06:19 PM	#5
Edward429451 Junior member Join Date: November 12, 2000 Location: Colorado Springs, Colorado Posts: 9,494	A lot of guys don't crimp for AR's at all and say no problemo. Ruger Mini-14's sre supposed to be crimped for. I settled on a light crimp and use them interchangably for both rifles. Overcrimping should be your concern I think. I've heard those horror stories too. I only use a 1/4 turn crimp and have had no problems. I used two pc's of 2X4 to check mine on a bathroom scale before I got the feel for the crimps on 5.56. Drilled a small hole in one that fit the base of a round and put the other one on the wood on the scale and went point down to 30, then 50 LBS and rechecked for OAL until I was satisfied .

March 30, 2007, 08:12 PM	#7
RERICK Junior member Join Date: July 9, 2005 Posts: 369	I've been using a Lee FDC for on all my AR rounds and have had no problems to date. Are you loading bullets that have a cannelure ?