crimping question

[jsickle]

Does anyone measure crimp they put on there handgun bullets, I have been setting the crimp to the loading manuals measurement with a empty brass after I measure all the brass length so they are the same then start loading.
Am i being to anal or is the crimp that important for performance or just to stop bullet creep.
Loading on a Dillon 550, 44mag and 357
Thanks

 

[CZ9shooter]

I just go by how it looks. And then + or - depending on the load. Nice and tight on hard hitters like 300gr 44 mag. But just enough to start curling the edge with light 38 specials to extend brass life.

You might have to try a few cylinders to see how much crimp you really need.

 

[kcofohio]

jsickle, are you going for magnum or plinking loads?

http://www.thehighroad.org/showthread.php?t=469815

Here is a link to give you some visual. Post #2 helps, as others.

 

[243winxb]

Setting crimp on 357 & 44

Set bullet OAL, no crimp. Back out seating plug/stem. Set the crimp by screwing the crimp die down by hand. When you cant turn it down any more, thats set. If loaded rounds (autos) dont pass the plunk test, turn the crimp die down a hair more.

 

[jsickle]

Kcofohio
Mainly shouting close to full house loads, I do load some light loads with Universal for my grandkids to shoot I crimp those loads also, sounding like I can get away with a lighter crimp on those

 

[Robert101]

Yes, what 243 stated. And, yes I measure with calipers as well. I also compare to factory measurements and try to stay close to the case mouth there as well. Plunk test them to help insure feeding. Then shot them to confirm proper function.

 

[rcmodel]

I have been setting the crimp to the loading manuals measurement with a empty brass

There is no crimp measurement shown in any of the numerous reloading manuals I have.

The cartridge case drawings at the head of each chapter is showing SAAMI Maximum for the cartridge.
Not how you should crimp them..

For instance, the 9mm drawing shows .380" as the case mouth measurement.

Actual factory taper crimp will measure .376" in all I have measured.

As for .357 & .44 Mag.

It is impossible to measure the roll crimp used on those calibers.

Just roll the case mouth edge into the bullet cannelure and call it good.

rc

 

[ku4hx]

For revolvers I go with the minimum roll crimp that works for that load. Some loadings get no crimp at all.

For semi-auto, same general logic applies but with a taper crimp in the last stage of the process. The idea is to get a round that fits and feeds from the magazine and drops freely into and out the gun's chamber. You have to pay attention to COAL too.

For me, that's .001"-.002" under SAAMI neck spec shown in pretty much every loading manual. It varies because cast boolits are fatter than jacketed or plated in most cases.