Do you need to use a crimp die for rifle ammo?

the question is vague ,but crimping the round does aid in consistincy and more even pressures and also stops bullet migration in magazine fed rifles with heavier recoil,but most loading manuals already tell us that
 
I started using a FCD for .223 I plan to shoot out of a semi auto after I had a malfunction that caused the bullet to get pushed into the case. I'm pretty sure it was a mag issue as after I tossed that mag the double feeds stopped, but I picked up the habit and I haven't stopped. It's on a progressive press so it takes no more time.

I reload for several rifles and that is the only clambering I use a FCD for.

I've never seen the benefit on a bolt gun.

Cheers!
 
If you are lading heavy bullets in a rifle with a tubular magazine, then a crimp is a good idea.

In other situations, neck tension alone should do the trick.

However, I have recently discovered that in 223 some cases are so thin in the neck that they have very little neck tension. I find the bullets falling out during the final tumble to remove case lube.

I have also recently discovered that light bullets in a case loaded with ball powder (150 gr in 8mm; 55 gr in 223) sometimes get poor ignition. Adding a neck crimp has saved me from having to scrap 1000 rounds of 223 loaded with regular primers and no crimp. These rounds were misfiring about 1:20. After crimping they are 100%.

All my future 223 will be neck crimped and use a magnum primer.
 
I crimp all my .308


Personally, it makes me reassured that the bullet is not going to fall out.

As mentioned, as well, some brass has such thin necking, you really don't have much of a choice...
 
my .223 die doesn't crimp, and I don't have a FCD so my handloads get shot in my bolt gun only.
reason being
I put a "dummy" round I made up in my AR15 and let the bolt slam it home and the bullet came out almost 1/8" just from the inerta, I know people do shoot un crimped rounds in their AR15's, but I wont be.
 
but crimping the round does aid in consistincy
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If crimping aided consistency, the bench rest shooters would all crimp, but they don't. Crimps are often used as band aids in cases where neck tension is inadequate. It's far better to have the proper neck tension, than to rely on a crimp to make up for inadequate neck tension. Crimping has a purpose when loading rounds to be used in tubular magazines, or with rounds that produce extreme recoil, or in some handguns, but in the case of most rifle rounds, it isn't at all required.
 
I crimp loads for leverguns, solids in big guns, cast bullets, and straight wall cases that have a flareing stage. For the most part if a rifle bullet moves under recoil the problem is lack of neck tension. Sometimes fixing that requires turning down the expander ball, sometimes its scrapping crap brass or crap/worn dies.
 
ganderite is dead on. only for levers.

many cartridges like MINIMAL neck tension, especially ultra precise cartridges. to the tune of only 1-2 thou, I have also seen crimping create substantial bullet run out
 
I don't normally crimp. But when I do it's usually for my semi autos. Normal neck tension is okay but a couple of times I had bullet setback through my M1 garand...I just record what ammo I make for which rifle and keep consistent. Or instance I only neck size for my bolt guns.
 
If the bullet I'm loading has a cannelure, I'll crimp it, as I believe it makes my ammo just a bit better. Its not so much a case of what is gained by any one step, as what is gained by the attention that is paid to every aspect of the process. At the worst there's no downside, if done properly, except for the moment of time it takes to do it. On the other hand, it produces a more uniform bullet pull weight, not unlike seating a match bullet into the lands. It does away with the effort spent endlessly attempting to find the sweet spot for jump to the lands. With powerful rounds that generate lots of recoil, it prevents the bullet from being driven down into the case neck from a number of rounds being fired over it. Anyone who has fired a powerful revolver knows that an uncrimped bullet will pull forward and tie up the gun as it exits the chamber throat. In a magazine rifle chambered for a powerful cartridge the effect is opposite as the nose of the bullet repeatedly impacts the front magazine wall, with the mass of the cartridge behind it. I discovered that in the case of the little .458, if the case mouth is not crimped, it catches the rim and belt of the case being ejected; although I consider this more a condemnation of straight wall rifle cartridges intended for use in bolt guns than of uncrimped bullets. If you have a tendency to push a fresh round over the remaining rounds in the magazine after firing, the cumulative effect on the second round in the magazine will result in a jam when you attempt to chamber it. As a rule I try to choose game bullets with cannelures, or better yet crimping grooves, but every now and then I get one without, like the Woodleigh .308/240, I just seat it so it will cycle through the magazine without catching, but I wish it had a cannelure.
 
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Crimping ammunition to be used in a semiauto is a safety must! I lost an AR15 upper (thankfully that was it) because of some rounds that were not quite crimped enough. The bullets got pushed back into the neck of the cartridge on their way up the feed path which caused a spike in pressure. Ka-boom!

A sure sign the bullets are infact moving back into the neckduring loading and throwing velocity and pressure all out of whack is when you notice your groups are all dead centre on the horizontal, but are varying wildly on the vertical.
 
Crimp for my 30-30, my 38-55 and my 357 S&W. That is it!!
Never have crimped any other rifle round in 45+ years.
Never have felt the need, either.
Eagleye
 
I have found with every .22 Hornet I have owned, they shoot better when crimped with the Lee Factory crimp die. I am not a big Lee fan but this is a case where their stuff works for me.
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I have never crimped for my 22Hornet, and my Anschutz easily averages sub 1/2moa.
 
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