I do a lot of reloading, but I am new to reloading for the AR-10. Is it necessary that I use a crimp die? It seems like I am getting pretty good neck tension without it (certainly enough for any bolt-action use), but do I need the extra security of a real crimp? Or is that just going to degrade accuracy without giving me any real benefit?
Oh Boy,....here we go again. :dry:
This is a "HIGHLY" debated subject no matter where the question is asked...If you look through the Reloading section you will find posts upon posts and threads on this very subject...it has even caused a couple of arguments between friends...
But never the less one has to ask to find out...what others think...
I personally use a "factory crimp die" when reloading..being that you are loading for a "semi-auto" because A. the manual suggests it....and B. given the force in which the round is chambered from the magazine...it is recommended...but as I said..this is highly debated in the reloading and shooting arenas....as for changing the accuracy..I have been told yes and no..so..personally I haven't noticed any real difference but I am not a Pro at reloading nor a Comp shooter so again...just my .25 worth...I do it for the piece of mind.
BMS
I use a Lee factory crimp die for ALL of my reloading. Even my single shots. It is supposed to give more consistent ignition, (according to LEE). That has to give less standard deviation of velocity and that can't hurt accuracy.
OK. Thanks, guys. I guess I should have done more homework. Nobody get into an argument on my account at least. I'll just have to take my time and figure out what works best in my gun
Yes, this is a hot topic. I've been flamed a time or two about my opinion, both here and on other web sites. However, for me, I DO crimp, using a Lee Factory Crimp Die. You're right to recognize neck tension as the key factor; the crimp just makes "sure". I gave up on taper crimping because, if not done just right, it can actually loosen the bullet by bulging the neck out away from the bullet. The Lee FCD avoids this. You can get by without a crimp, but -- in my humble opinion -- it increases the risk of an accident. The military specifies a crimp for a reason, as do most loading manuals when it comes to gas operated semi-auto guns. The Sierra Handloading Manual, version V (5), has a great chapter on this.
For those who don't believe in a crimp on gas guns, I only say to each his own. I don't crimp for my bolt guns, but do for levers and autos.
Bringsteen wrote: OK. Thanks, guys. I guess I should have done more homework. Nobody get into an argument on my account at least. I'll just have to take my time and figure out what works best in my gun
Hey...No Worries...as I said...we have to ask to learn...Listen to Hank...He knows his STUFF....and is well respected on this Board...even if his presents isn't seen much... :dry:
Hank...Nice of you to join us again my Friend.. ..Your input has been missed...hope we see more of you in the future...YOU are always a welcome member...and as one of our senior reloaders...I can say...we need your input more....
Again...good to see you on the board again....
BMS
I have always used the LEE Factory Crimp Die as recomended by Lee. I crimp all my loads and have never experienced any degradation in accuracy. All of my AR's both 5.56 and 7.62X51 shoot MOA or less so I tend to believe Richard Lee and his writings on the subject.(more even ignition with the crimp etc..) I have also crimped factory ammo for several friends who have experienced 'set back" with unfired rounds in thier AR mags. So I would have to say yes, crimp for your autoloading rifles and pistols.
I don't currently crimp for my AR-10 but have a LFCD and if you're going to crimp, it's the way to go. That said, I've had to modify my expanders on my sizing dies to get a .003" tight neck for gas guns. The dies as they come are set to about .001 under bullet size and while good for a bolt gun, is not enough for a semi. I've done this for both .308 & .223 dies. My intent is to, once I have loads worked up, shoot 10 shot strings of crimped & uncrimped loads over a chrono and for group size to see the effect of the crimp and either validate or not Lee's claim. Not there yet.
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