Cannelure for AR-10 reloading or not?

[guns1869]

Hey guys.
I'm a newbie with forum chat so school me if I'm messing up the protocol here...
I reload pistol and .223/5.56 and am now delving into the world of long(er) range shooting.
I bought an Armalite SuperSASS and will be shooting handloads. I have Lapua brass and I bought a bunch of 168gr Hornady A-Max only to notice later that there is no callelure. I've been told that not having a cannelure when shooting semi-auto is bad but it seems that many of the knowlegable shooters are doing just that.
BL: Is it OK to handload without a cannelure for AR-10?
Any advice/experience shared is geatly appreciated!
Vr,
Pete L.

 

[BCP]

Re: Cannelure for AR-10 reloading or not?

I thought a cannelure was put on a bullet for crimping purposes.

I don't crimp anything and haven't had any problems.

 

[guns1869]

Re: Cannelure for AR-10 reloading or not?

Thanks BCP. The way it was explained to me is that the recoil jolts the ammo in the magazine and in accordance with newton's third law of motion could undesireably seat the bullets further in the casings, affecting accuracy or worse, increase pressures... I've been told that this is the reason you want to crimp ammo in semi-auto weapons and like you said, use the cannelure on the bullet to seat the crimp.

 

[Victor N TN]

Re: Cannelure for AR-10 reloading or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Guns1869</div><div class="ubbcode-body">Thanks BCP. The way it was explained to me is that the recoil jolts the ammo in the magazine and in accordance with newton's third law of motion could undesireably seat the bullets further in the casings, affecting accuracy or worse, increase pressures... I've been told that this is the reason you want to crimp ammo in semi-auto weapons and like you said, use the cannelure on the bullet to seat the crimp. </div></div>

The things you mention above are all what we are told in basic handloading school. (Where ever that magical place is). While MOST of my loads for semi auto rifle are crimped w/ cannelure, the long range loads for my M1-A ARE NOT. But in all honesty I have a pretty tight neck tension on the 175 Bergers.

When I was in your shoes, I tried a few with and a few without crimping. Load them in your magazine and cycle them 5 or 6 times and then measure them. If there is a significant difference, stop and rethink. Cycle them, shoot them, record your targets, see if it makes a difference in YOUR rifle.

You'll probably get at least 10 replies on here and at least 10 different answers. The match grade AR-15 I used to have actually LIKED a little crimp.

 

[guns1869]

Re: Cannelure for AR-10 reloading or not?

Thanks Victor! Good stuff. What about a slight crimp on a bullet without a cannelure? Suggested? Possible? (understanding that for accuracy reasons it will depend on the rifle)

 

[BobinNC]

Re: Cannelure for AR-10 reloading or not?

Guns,

You can use a Lee Factory Crimp Die. It will cleanly crimp on bullets with no cannelure.

 

[BCP]

Re: Cannelure for AR-10 reloading or not?

I found that even with a lee crimp 175 SMK's would "jump" forward a few thousandths when chambered. Amax don't move though. Rifle is more accurate than I am with either bullet.

Try whatever dies you already have, if they don't work then buy whatever you feel that you need.

 

[Victor N TN]

Re: Cannelure for AR-10 reloading or not?

In the case of using the crimp die for neck tension, that's an unknown that you can enter into the ammo equation. I know others that do it. But it is usually a question mark on that ammo, or ammo loaded like that.

While I don't at this time own a Lee Factory crimp die, I agree with the basic theory. I believe that there are advantages to using it for a crimp. But here again, you are playing with an unmeasured variable to put neck tension on your cases. If all the cases have the same wall thickness on the case necks, and you exert the same pressure against the press handle, you may be OK.

Good luck.

 

[guns1869]

Re: Cannelure for AR-10 reloading or not?

Lots to consider. Thank you all for the puts!
Followon question for the pros: Will a regular full-length RCBS die set work for ~500+ yard precision shooting or is it worth the extra money to go for the competition die set?
Again thanks for the help!
Vr,
Pete L.

 

[Victor N TN]

Re: Cannelure for AR-10 reloading or not?

I loaded "match" quality ammo for many years before "MATCH" dies were commercially available.

 

[guns1869]

Re: Cannelure for AR-10 reloading or not?

Thanks a lot guys. I really appreciate you taking the time to school me up! BL: bought a Lee crimp die and an RCBS FL die set and I'm off to the races. Take care!
Vr,
Pete L

 

[shooter19802003]

Re: Cannelure for AR-10 reloading or not?

+1 onn the lee crimp die. I crimp all of my semi auto stuff. I do it for consistancy. Not all of my semi auto brass is neck trimed in\out. I shoot so much of it I just don't have the time to. So with the crimp I get consistancy. I know there is consistant neck pressure that way. Good luck

 

[guns1869]

Re: Cannelure for AR-10 reloading or not?

Thanks shooter!

 

[bignada]

Re: Cannelure for AR-10 reloading or not?

If you use a Redding Type S Full Length Bushing Die you can control neck tension very reliably. No match bullet I have ever used contains a crimping cannelure.

Try removing several .0000s from your sizing dies neck expanding ball. You can chuck the decap rod assy in a hand drill and using sandpaper or a file, remove some material from the circumference of the expansion ball. Be sure to smooth to a nicely honed finish and remove any sharp shoulder edges; you don't want to strain or pull on the brass as the expander ball comes back through the neck.

The Redding S has a plain decap pin holder, plus expansion ball so if your brass neck is concentric you won't need to use the expander ball at all anyway...

Might try sizing a fired brass w/o the decapping rod in place and placing your bullet or miking the diameter of a sized case neck from your sizer die before doing much more than polishing your sizer ball.

Neck tension is better than a crimp in my experience unless hunting dangerous or large game that can/will kill you...