Why Is Crimping Necessary?

Does crimping affect accuracy?

Some loads need a good crimp to burn well and get good start pressure.

Crimp can indeed make a difference in how the powder burns and affect the ES & SD numbers.

Accuracy may or may not be affected, just have to test it..

Does Cannelure affect accuracy?

a cannelure is never regarded as desirable accuracy-wise as it distorts both jacket and core to some extent or other and adds another potential source of inconsistency and/or ruining the bullet’s concentricity.

What is the purpose of crimping a bullet?

A firm taper crimp on ammunition intended for use in an autoloading firearm is intended to do exactly the opposite; to prevent the bullet from being forced deeper into the case during the feeding cycle. It also serves to ensure reliable feeding by eliminating the sharp edge of the case mouth.

Do you need to crimp 308?

No need to crimp a 308 as far as I know. I crimp the majority of my revolver reloads, and anything tube fed that will cause a bullet to set back in the case when it’s fired, but thats it….

Does case length affect accuracy?

Case length isn’t very critical to accuracy unless the case is so long it exceeds the neck portion of the chamber. I have a case length gauge good for quite a number of cartridges. I check cases with that and if they don’t exceed the maxinum length indicated on the gauge, I don’t trim them.

Does Lee bullet seating die crimp?

To answer your question, yes the seating die also crimps when properly adjusted. What cartridge are you reloading? On the Lee 3 die pistol sets the bullet seating die crimps also.

What happens if you over crimp a bullet?

If you crimp too much, you’ll get a round that won’t chamber or won’t shoot accurately. I have a sample that was over-crimped into a jacketed . 45 ACP 230-grain roundnose, and when the case couldn’t be crimped any more (the hard bullet stopped inward progress) the case then buckled.

Is crimping a bullet necessary?

So, normally, there is no need to perform a separate crimping step with a bottleneck rifle cartridge. If the projectile (bullet) you are using has a cannelure band, you can apply a crimp to help secure it in place, but you don’t have to. … If your bullet does not have a cannelure groove, then do not use a crimp.

Do you need a factory crimp die for 9mm?

No you don’t have to use the Factory Crimp die but you can if you want to. It is a little easier to remove the flare with the fourth die, in a separate station, than it is to do it while seating.

Do you need a factory crimp die?

The term, “crimp” for straight walled pistol ammo is a bit of a misnomer. The short answer is, yes, a crimp is needed. But what that really means is to “crimp” just enough to remove the flair that was made by the expander die. It is critical to do no more than that with plated bullets, or that will damage the plating.

What is a factory crimp die?

Factory Crimp Die Only. Lee Factory Crimp Die crimps your bullets in place the same as factory ammo. A collet gently, but firmly squeezes the very end of the case into the crimping groove, exactly the same as factory ammo.

Do you have to crimp 45 ACP?

Yes, crimping is a necessary step. The crimp is needed to remove the flare applied with the expander die. That doesn’t mean you have to crimp with the Lee Factory Crimp die though, you can also apply the crimp with the seating die. Either as the bullet is seated or as a separate step after the bullet is seated.

Do you crimp 223 reloads?

No. It really hasn’t been an issue. I would only crimp if I had issues and only crimp if the bullet has a cannelure. Try your loads without a crimp first and go from there.

Is it necessary to crimp 9mm?

No need to crimp 9mm. All you need to do is get rid of the flair the powder/expander die put in.

Is it necessary to crimp 223?

223 ammo didn’t have crimped in bullets. But they test those bullets for accuracy without crimping them; better accuracy is hand. But it’s not as good as the same bullet without the cannelure rolled in; proof that along unbalanced bullets enough to make them less accurate – even without crimping.

Does crimping increase pressure?

Increasing crimp increases the start pressure of the round by making the bullet take a little longer to free up and start moving. However, this all happens when the pressure is low on the rising portion of the curve.

Can you roll crimp without a Cannelure?

During crimping, the case mouth flattens out the small fins when it is rolled into the bullet. A roll crimp should not be applied to any cast lead bullet that does not have a crimp groove, or any plated or jacketed bullet without a cannelure.

Do you need to crimp .38 Special?

It is certainly not necessary but does a good job if you want to seat and crimp in separate steps. That is usually not necessary either with 38 Special. I’ve only been reloading revolver rounds for about a year.