Are crimp dies worth using? I just bought a 3-pack of lee dies in .223 and they came with a crimp die. Is it worth using the crimp die to "improve uniform start pressures" ?
Thanks,
Jay
Thanks,
Jay
Crimp Dies?
- Thread starter JLP2003
- Start date
Re: Crimp Dies?
In a semi-auto, you can use 0.003 neck tension, or a crimp on the neck. Either one will prevent bullet setback/slamforward as the action cycles.
In a semi-auto, you can use 0.003 neck tension, or a crimp on the neck. Either one will prevent bullet setback/slamforward as the action cycles.
Re: Crimp Dies?
I've loaded for gas guns in 308 Winchestger, 30/06 Springfield, 223 Remington and 458 SOCOM and haven't crimped for any of them. This of course applies to rifles and not to handguns.
I've loaded for gas guns in 308 Winchestger, 30/06 Springfield, 223 Remington and 458 SOCOM and haven't crimped for any of them. This of course applies to rifles and not to handguns.
Re: Crimp Dies?
JLP2003 give the FC a try, it may improve things for u. i use a light FC on my 308 match loads, and it did reduce vertical group size a bit. on other guns ive seen no change
JLP2003 give the FC a try, it may improve things for u. i use a light FC on my 308 match loads, and it did reduce vertical group size a bit. on other guns ive seen no change
Re: Crimp Dies?
I gave up crimping rifle ammo about 35 years ago.
Rationale: 30.06 Military Match for M1 Garand is not crimped.
7.62 Military Match for M14 and M1 is not crimped.
Federal Match ammo is not crimped.
Rem/Win Match ammo is not crimped.
5.56 Match ammo today is not crimped.
Now 357 Magnum I will crimp just to add to bullet pull in order to burn more propellant before the bullet starts to move. Also to stop bullet creep in revolvers with hot loads.
Best way to ruin bullet accuracy is to put a cannelure on it. Sierra will tell you their 150 FMJBT bullet does not shoot as well as any other 150 gr. bullet they make that have no cannelure. If you happen to have a barrel that will swage the bullet down enough to negate the cannelure you may get away with it but I have never seen or heard of one. Note: I do have a 30 cal barrel that runs .298X.3055 that shoots them pretty fair but nothing to write home about.
Best way to ruin match bullets is crimp them as they have no cannelure. Lake City did a experimental run on 69 gr. FMJ bullets back in 60s that had no cannelure. The DSs at LC crimped every last round and the accuracy was terrible as compared to the rounds hand loaded and not crimped.
Crimping of 30.06 was done because of the Browning 1917/1919 guns. On these systems the bolt comes much further to the rear in cycling than does the M1/M14 type system. Belt guns need lots of bolt velocity/energy to strip rounds from the links and still chamber the round thus the bolt has really picked up speed before contacting next round which can set a bullet back in case a bit. The M1/M14 has about 1/10th of the overtravel a belt gun has and thus has not picked up bolt velocity enough to hurt things.
Same thing for M60/M240 guns.
Since ammo is interchanged among the troops (striping belts/ loading belts) there is no control over what ammo goes in which weapon so they try to make it idiot proof and crimp everything as a safety factor.
As a rule of thumb I want my rapid fire ammo seated with about .003" neck tension (neck is .003" smaller than projo diameter). On bolt guns it is less.
I gave up crimping rifle ammo about 35 years ago.
Rationale: 30.06 Military Match for M1 Garand is not crimped.
7.62 Military Match for M14 and M1 is not crimped.
Federal Match ammo is not crimped.
Rem/Win Match ammo is not crimped.
5.56 Match ammo today is not crimped.
Now 357 Magnum I will crimp just to add to bullet pull in order to burn more propellant before the bullet starts to move. Also to stop bullet creep in revolvers with hot loads.
Best way to ruin bullet accuracy is to put a cannelure on it. Sierra will tell you their 150 FMJBT bullet does not shoot as well as any other 150 gr. bullet they make that have no cannelure. If you happen to have a barrel that will swage the bullet down enough to negate the cannelure you may get away with it but I have never seen or heard of one. Note: I do have a 30 cal barrel that runs .298X.3055 that shoots them pretty fair but nothing to write home about.
Best way to ruin match bullets is crimp them as they have no cannelure. Lake City did a experimental run on 69 gr. FMJ bullets back in 60s that had no cannelure. The DSs at LC crimped every last round and the accuracy was terrible as compared to the rounds hand loaded and not crimped.
Crimping of 30.06 was done because of the Browning 1917/1919 guns. On these systems the bolt comes much further to the rear in cycling than does the M1/M14 type system. Belt guns need lots of bolt velocity/energy to strip rounds from the links and still chamber the round thus the bolt has really picked up speed before contacting next round which can set a bullet back in case a bit. The M1/M14 has about 1/10th of the overtravel a belt gun has and thus has not picked up bolt velocity enough to hurt things.
Same thing for M60/M240 guns.
Since ammo is interchanged among the troops (striping belts/ loading belts) there is no control over what ammo goes in which weapon so they try to make it idiot proof and crimp everything as a safety factor.
As a rule of thumb I want my rapid fire ammo seated with about .003" neck tension (neck is .003" smaller than projo diameter). On bolt guns it is less.
Re: Crimp Dies?
I use the Lee FCD for some loads but not all. I have never done any type of comparison to see what they would do accuracy & velocity wise of crimped vs. not crimped but maybe I will try it out sometime. I have just recently been bitten by the long(er) range bug and up until recently I would say 70% of my rifle shooting has been semi-auto. My bolt gun loads I typically do not crimp but those loads also get a lot more attention to detail in regards to neck sizing, bullet tension, etc.
I use the Lee FCD for some loads but not all. I have never done any type of comparison to see what they would do accuracy & velocity wise of crimped vs. not crimped but maybe I will try it out sometime. I have just recently been bitten by the long(er) range bug and up until recently I would say 70% of my rifle shooting has been semi-auto. My bolt gun loads I typically do not crimp but those loads also get a lot more attention to detail in regards to neck sizing, bullet tension, etc.
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