Campro .45 230gr fcp rn Crimp Dia.

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WereWeasel

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Does anyone find the crimp diameter @.464 of these projectiles excessive? My charge right now 6.3grs of autocomp (cheapest powder at my local gun shop). After firing, sizing and belling there is still a definitive crimp ring. Is the crimp excessive or is the low pressure nature of the round just unable to push the walls of the case against the chamber to iron them out?

Other information to give it's a para 1911 with a 5" match ramped barrel, dies are lee carbide and cases are once fired r-p out of a glock 21. No signs of blow back or over pressure and everything cycles great. Just a little concerned about the crimps effect on case life.

Thanks in advance!
 
I don't think I have ever bothered to measure crimp on any pistol round. If you think it's an issue then just back off. Unless you are using an 22+lb recoil spring I doubt you'll ever have any issues with setback.
 
After running into some issues with the Lee seating and crimping die I purchased a Lyman tapered seat die and never looked back. Much easier if you have any case length variation at all.
 
I taper crimp to .473 at the case mouth which is SAAMI standard

Campro's listed crimp to .464 is what 'they' used for their particular loads to generate the load data they publish. I see no need to crimp that hard.
They are building more pressure with less powder. For example their listed Max of 5.3 Win 231 is pretty much the Min for everyone elses load data with very little crimp.
 
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Best check around. That is a over hard crimp, me thinks. .473 or a bit more is what I use in a PARA. Cam-pro crimped that hard may strip the wash off the bullet.
 
The SAAMI drawing for .45 ACP specifies the diameter at the case mouth as .473" -.006", so a minimum of .467". A crimp diameter of .464", per the Campro data, is excessive and I would be worried about deforming the bullets. .469"-.471" is a reasonable crimp.

The objective of taper crimping is to go just a little bit more beyond removing the flaring of the case mouth.
 
Thanks for the replies guys! I adjusted it back to .468. I know that .471 is too little because I accidentally dropped my test dummy on the table (about 12") and drove the bullet flush into the case.
 
WereWeasel said:
Thanks for the replies guys! I adjusted it back to .468. I know that .471 is too little because I accidentally dropped my test dummy on the table (about 12") and drove the bullet flush into the case.
Click to expand...

Are you doing a roll crimp or a taper crimp? How much are you belling the case?

I load the same Campros and with a taper to .473 - .472 and I cannot force a bullet into the case.

Just tested one by dropping it 3 times on the head of the bullet from a foot above my reloading bench. The force dented the plywood but the bullet did not move.
 
I use Lyman type "M" expanders, on the second step of the expander does not bell the case mouth. The case mouth is only opened a few thousandths larger than bullet diameter. And this allows the bullet to start into the case without tilting.

A taper crimp does not hold the bullet like a roll crimp, the taper crimp is only for streamlining the case mouth for feeding. The bullet grip is controlled by the die and expander meaning how tightly the case holds the bullet.

Below lay a straight edge on your loaded rounds before and after the taper crimp. All that is needed is for the case mouth to be just a few thousandths smaller to be streamlined for feeding.

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And remember very few people trim their pistol cases so the cases will vary in length. Meaning the amount of taper crimp will also vary and the longer cases having more crimp.

This is why Lee made the factory crimp die with the carbide ring in its base. It will size and remove any bulge below the crimp on the longer cases.

Below is a example of the Lyman type "M" expander for a .223 and it shows the case mouth on the second step is only .002 larger than bullet diameter. This easily allows the bullet to start into the case and not over expand the case mouth. This prevents over working the case mouth and splits at the mouth.

ohIUcpd.png
 
Paul_T said:
Are you doing a roll crimp or a taper crimp? How much are you belling the case?

I load the same Campros and with a taper to .473 - .472 and I cannot force a bullet into the case.

Just tested one by dropping it 3 times on the head of the bullet from a foot above my reloading bench. The force dented the plywood but the bullet did not move.
Click to expand...

Taper crimp; I bell just enough that the mouth just clears the rad at the base. I'll give it another go at .471 when I buy another 500 and see maybe there was an error on my part, I know after I noticed it pushed back I recrimped 100rds to .468 just to be sure. I'm looking to get the least amount of crimp while being able to fumble one on the ground an left to wonder.
 
So bought another 500 crimped to .471; dropped on the bench, bounced on the bench, even dropped on the floor nose down. DID NOT BUDGE! Clearly messed up those initial test crimps.

Thanks for the help men!
 
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