45 ACP 230gr FMJ, how much crimp?

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ferggie

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I am loading some 200gr LSWC and have been informed that I should have a crimp giving me .469" at the top.

What crimp should I achive for a 230 gr FMJ?
 
The same if that's all that's needed to remove the flare. Don't be stuck with thinking that you have to achieve a specific dimension for the crimp. All you need to do (all you SHOULD do) is remove the flare for the particular bullet you are loading. The dimension can range from .469 min. to .472, maybe more. Dropping a test round in your barrel will tell you when you've reached your maximum crimp dimension.
 
Depends on the chamber size of your pistol barrel and the diameter of the bullet.

For .452" diameter lead bullets, M&P45 will pass the loaded round drop test in the barrel and reliably feed/chamber taper crimp up to .473". For tighter chambered Sig 1911, up to .471"-.472" taper crimp will pass the drop test and reliably feed/chamber.

Many shooters use .470" taper crimp, but I am a bit OCD and want my case neck to seal tighter against the chamber during firing for more consistent chamber pressures (Some will argue this point, but that's what I do for pursuing accuracy).

For .451" diameter bullets, I use .470" taper crimp.
 
In my limited experience, the crimp matters in the reliability of the round to consistently feed. I load only 200gr, and in my kimbers, if my crimp is much over .471 I get 3-point-jams. My loads are typically .4695-.470 and I do not have any 3-pt-jams. If all you do is static target practice, probably not a problem. But I also try and compete in IDPA and USPA, so my loads need to be reliable.
 
http://www.thehighroad.org/showpost.php?p=6284211&postcount=63

About this much

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No Crimp! Don't thnk of it as a crimping operation. It is a "de-flaring" operation done by a taper crimp die. The "thunk test" will tell you how much to straighten the case mouth...

Thunk test; remove barrel from gun, drop loaded round into chamber, round should easily drop to flush with thr bbl. hood (thunk), and fall out when bbl. is inverted.
 
GI issue 230 grain Ball and National Match ammo comes out of the box measuring .469" to .471", depending on the manufacture.

It also comes out of the box measuring 1.266" to 1.271" OAL.

That's going to be pretty much what it should be, as long as your bullets are GI FMJ-RN profile.

rc
 
I don't crimp or bell cases at all, if bullets fit snugly,Rem cases seen to be either softer or thinner so when useing them I just run them in the seating die,a tad,not really a crimp. biker
 
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