45colt question

[josper]

I have been loading the lyman 452424 255gr bullet at 1.640 OAL. The manual says the correct OAL is 1.575 roll crimped over the forward driving band leading edge. This looks kind of funky and I would rather roll crimp into the crimp groove. It looks better and I should think it would hold the bullet better to keep it from moving back on recoil. It seems to shoot just fine .What do you 45 colt guys think? Is this ok?? As another example ,the RCBS 45-270SAA bullet the OAL is 1.640 crimped into the crimp groove. I just get nervous when ever I deviate from the manual as I do believe in adhering to the manuals for most everything.

[scattershot]

I always crimp in the crimp groove, if the boolit has one.

[littlejack]

josper:
If your loads fit in the chamber and do not stick out the end of the cylinder (it doesn't sound like they do) you are fine. Your boolits seat less than the book calls for, so that will calculate into less pressure ( more case capacity).
If you were to seat deeper than what the book called for, or deeper to get the cartridge to fit in the chamber, that is where you would be getting into trouble (more pressure).
Reguards
Jack

[44MAG#1]

Crimp in the crimp groove. Lyman adhered to the SAAMI spec's OAL length for the 45 Colt cartridge.
Since they seated deeper than crimping in the crimp groove would give pressure will be less with the loads they list.
As with anything else in life some common sense needs to be used.

[josper]

Thanks guys. I was sure it was ok ,just needed to hear it from someone else.

[Silver Jack Hammer]

The 454424 and 452424 have not been entirely standard down through the years, and Ruger chambers tend to run tight, so seating over the driving band is the solution to the problem of rounds that fail to chamber. Sounds like you don't have this problem.

Somebody wrote an article a few years ago with pics of differenct 454424's, RCBS versions and 452454's side by side, there was an obvious difference in where the crimping groove was on the different designs.

My SBH won't chamber 44-250-K when crimped in the crimping groove so I have to crimp that boolit over the driving band. Then I cut the charge of Unique by 10 per cent.

[44man]

The 454424 and 452424 have not been entirely standard down through the years, and Ruger chambers tend to run tight, so seating over the driving band is the solution to the problem of rounds that fail to chamber. Sounds like you don't have this problem.

Somebody wrote an article a few years ago with pics of differenct 454424's, RCBS versions and 452454's side by side, there was an obvious difference in where the crimping groove was on the different designs.

My SBH won't chamber 44-250-K when crimped in the crimping groove so I have to crimp that boolit over the driving band. Then I cut the charge of Unique by 10 per cent.
No reason why not unless throats are too small. It is not cylinder length.
Overall length things in books are silly when a boolit has a crimp groove and it does not stick out the front.

[white eagle]

I always crimp in the crimp groove, if the boolit has one.

+1...

[kwilfong]

+ I don't think revolver bullets would ever move deeper under recoil. I could see them creeping forward & tying up the cylinder with little or no crimp. Semiautos are a different story & one could run into serious trouble if bullets got bumped deeper into the case during feeding. Don't ask me how I know ; (

[Silver Jack Hammer]

Found the article about crimping over the driving band when your mold is of the bad 454424 design rather than the good 454424 design. It's in Handloader 260 June 2009 by Roger Smith. Title of the article is Understanding the 454424 on page 76. Shows pics of two 454424 boolits side by side. The crimping groove is closer to the base on the bad design making the nose longer. The article states the too long nose from the crimping groove being too close to the base make the loaded cartridge too long to chamber in Colt-length cylinders. I've never seen anyone encounter this personally. Shows crimping over the driving band and states Lyman recommended this from 1967 to 2008. Personally I owned a 454424 from 1982 to 1990 something and crimped in the crimping groove and loaded and shot the boolit from my Colt SAA .45.