.45 acp crimp

[jrd541280]

I crimp in a step itself. Seat first them come back and crimp, just me. I don't shoot competition, but I do want reliability and accuracy. The reason is as Mike stated, I don't trim my auto cases do to the shear volume. I do however seperate by headstamp. I have found that seating and crimping in one step will cause oal's to vary by 10 to 15 thousandths. The reason is a longer case will crimp on the bullet sooner causing a longer oal. And possibly gouging the jacket or bulging the case or both. I'll seat, back out the plunger and then run 10 or so to get the feel of the lot i'm running. I'd much rather have a little to light or to heavy a crimp than jamming a crimped bullet to its resting spot. Again, just me.

 

[jrd541280]

BTW, sasquatch doesn't believe in us either

 

[DizzyJ]

Say it this way............

Revolver cartridges (like the .38 Special or 45 LC) need a roll crimp. You don't want the bullet jumping forward (due to recoil) to tie up your revolver. The die makers have built this feature into their die sets (when properly adjusted).

A cartridge that headspaces on the rim of a case (like the .45 ACP or .380 ACP) uses a taper crimp. It's less pronounced then your roll crimp. The die makers have built this feature into their dies (when properly set). It's usually GTG as long as the cartridges feeds reliably from the magazine and retains it's OAL. Another obvious error happens when your bullets have telescoped back into the case. OMG.

Line drawings, Q. What is the difference between a roll crimp and a taper crimp?
http://www.frfrogspad.com/miscellg.htm

Bottle neck rifle cartridges usually work on the with "just enough crimp to get the job done." Huh? Well, because of the various ways to feed a cartridge, the amount of crimp will depend. Think about a cartridge fed from a tube magazine (like a Winchester lever action) or a cartridge fed from a auto/semi-auto rifle w/ a magazine (like an M16) or a cartridge fed into the chamber (like from a bolt action). And, of course the single cartridge just fed directly into a chamber (break open single shots). So, it'll depend. Accuracy buffs also use "just enough crimp" or even just "neck tension"......of course they experiment with the right amount of tension for maximum accuracy. Then, some shooters also like factory crimp dies to get that uniformity in their crimp (like factory new ammo). Whatever, it's your choice. But in the end, you don't want to crimp it so strongly that you deform the bullet (that ruins accuracy), you don't want to have your bullets telescope back into the cases and you don't want to unduely raise pressures to dangerous levels with too strong of a crimp. Conversely, a crimp that is not strong enough, might leave you with your bullet stuck in the chamber. Should you decide to extract the cartridge without firing it.

Aloha, Mark

Agreed.

 

[Crohnos01]

BTW, sasquatch doesn't believe in us either

Yes I do

 

[Mikej]

It's not unheard of..

View attachment 349673

View attachment 349674

But people believe Sasquatch exists as well so I guess the inverse is true.


Hornady American .45 ACP die on left with very good taper and easily visible. RCBS .45 ACP die on right... taper or roll?
View attachment 349675
The left photo I took from my turret.

The right photo was sent to me by an unnamed source.


I'm really not being a dick, I am very patient and know that nobody knows everything and I've been shown wrong a time or two, three, hundred.

When the die set is unknown and the reloader is new, the term "crimp" is crimp. They would ASSUME whatever die they have is the type we all refer to. Took me a while to get the terminology down and understand so when I had dies they had the proper crimp TYPE in them.

Don't worry, I don't see you being a dick at all. As a matter of fact you are an asset to the board, willing to go out of your way to help. Getting into your machine and getting photos! Swell! I work at expressing myself and am lacking in that ability.

I've never actually got in and looked close at my crimp dies. I do know that expander dies have different shaped expanders in them. The Lyman .45 acp was better than the RCBS.

I'll just hope the OP get's that "Feel" for what's right, SOON, before he gets frustrated.

 

[Tilos]

I don't mean to jump into this discussion, as I recall "crimp" was a recent topic in another thread (could have been @Josh89 mega thread, but I will...

I posted this:
45 ACP Crimp(?)
45acp is not really crimped as much as "de-flared" as it head spaces on the front edge of the case.
The "press fit" of the bullet into the expanded case holds the bullet in place, NOT any crimp.

The amount of "de-flare" is a diameter that is the sum of the bullet diameter plus 2x the case wall thickness measured at the case mouth of a completed round.
Not just some arbitrary number because wall thickness and bullet diameters vary.
If the edge of the case is "shinier" than the area just below it, it has been "coined" into the bullet and de-flared ("crimped") too much, and possibly bulged near the base.

Even if there is a small gap between the case edge and bullet, the plunk test is what determines if the de-flare amount is enough.
jmo

Edit: A Lee FCD is not always the "fix" but often just a repair for over "de-flaring" and will reduce the size of cast bullets to jacketed bullet diameters, as well as re-sizing the bulged case.
I never understand why pics of crimps into revolver bullets with crimp grooves are posted in 45acp/40sw/9mm/380 threads

 

[Member 5605]

Edit: A Lee FCD is not always the "fix" but often just a repair for over "de-flaring" and will reduce the size of cast bullets to jacketed bullet diameters, as well as re-sizing the bulged case.
I never understand why pics of crimps into revolver bullets with crimp grooves are posted in 45acp/40sw/9mm/380 threads

Roll crimp is roll crimp.

Because when somebody has crimping that's causing bulging in the case because it's too tight and you don't know if they have a taper or roll crimp for their .45ACP die...

Please look up a .45 ACP roll crimp die and tell me they don't exist.
I'll save you the search:
RCBS Roll Crimp Seater Die 45 ACP 45 GAP

Do we know absolutely for 100% sure it's not a roll crimp .45 die?

Everyone here assumes that there is no such thing but to cover all bases we must cover all possibilities - roll and taper!

Maybe I should put the macro lens on the camera and take some quality photos of taper crimp with measurements?

New reloaders don't always know what crimp the die set has. They see the big numbers and buy the dies not realizing it's the opposite crimp they desire.

I for one love giving people the benefit of the doubt.

 

[Tilos]

Roll crimp is roll crimp.

Because when somebody has crimping that's causing bulging in the case because it's too tight and you don't know if they have a taper or roll crimp for their .45ACP die...

Please look up a .45 ACP roll crimp die and tell me they don't exist.
I'll save you the search:
RCBS Roll Crimp Seater Die 45 ACP 45 GAP

Do we know absolutely for 100% sure it's not a roll crimp .45 die?

Everyone here assumes that there is no such thing but to cover all bases we must cover all possibilities - roll and taper!

Maybe I should put the macro lens on the camera and take some quality photos of taper crimp with measurements?

New reloaders don't always know what crimp the die set has. They see the big numbers and buy the dies not realizing it's the opposite crimp they desire.

I for one love giving people the benefit of the doubt.

Sorry if you took offence to me mentioning of roll crimps not being appropriate here.
Never said that don't exist.
If you read the reviews at that die you linked to, you'll see the users use it for special applications, not 45 acp.
If you click the overview tab at that link, it says this:
""Roll crimp is designed for use with heavy recoiling revolver cartridges. To seat bullets without crimping, simply unscrew the die until the crimp ring no longer engages the case mouth.""
Thanks for the link, info there clarifies my point.

I'd guess most all 45 acp die sets are sold with a "taper crimp" seating/crimp die, and referencing a roll crimp used with grooved bullets, mostly for a revolver, can be confusing to some newbs.
He could be loading for a revolver, usually head spaced via moon clips (I do), but I doubt it.
Just trying to clarify the de-flaring, without coining/bulging needed on common everyday 45 acp loads.
I'm not looking for a pissing contest here.

 

[Member 5605]

I'm not looking for a pissing contest here.

Me either. I'll eat crow when necessary and I'm not afraid to lick the spoon after I stir the pot.

I'm looking at all content posted on this forum as permanent information that's able to be resourced years from now which is why I'm looking to cover all options not just here and now but later. I'm instructional by nature and very thorough with explanations and details (give me a book and I can't read, but give me technical data and I remember it). I've looked for technical data before and you find 10 threads about the same thing and everyone says the same thing but only one post has the relative information.

We have all seen those RCBS (most notorious) die sets from wayyy back that get passed around like the joint at a Rastafarian party and sometimes old timers slip something in there that's not on the original die set (I have one of these sets I got from a member on here, it's perfect unless I want to seat round nose bullets). Their instruction gets lost after the first transaction and down the road a new reloader ends up with a $15 set of dies from an estate sale..... bam! They run into bulging brass. Just covering all aspects here, not just new die sets.

Disclaimer aside, we are absolutely in agreement that 'most new dies' do come as they should be with proper crimp depending on the cartridge.

 

[jrd541280]

Ok, yeah, they do. All the internals, proper type crimp for proper type cartridge. This is not a ballasisticians thread. I myself, have entered the " crimp zone" It is a universe of human opinions.
That's why we discuss these issues and come to an inconclusive decision as to what the op asked.
For me, 45 auto. Follow your data in your manuals. Shoot em, and give us your report.

 

[Seared Saba]

is it normal for the crimp to mark the bullet or is it to much crimp.i set one a little to far and pulled it back out and noticed a mark on the bullet from the crimp.it was noticeable but it didn't break the copper plating.just curious if I have to much crimp.

I go by the number, between .468″-.470″ at the case mouth for .451 projectiles.

 

[Tilos]

Ok, yeah, they do. All the internals, proper type crimp for proper type cartridge. This is not a ballasisticians thread. I myself, have entered the " crimp zone" It is a universe of human opinions.
That's why we discuss these issues and come to an inconclusive decision as to what the op asked.
For me, 45 auto. Follow your data in your manuals. Shoot em, and give us your report.

Yea, the "crimp zone"...
right up there with "tumbling zone" media/method/additives/duration/dust control/disposal/etc.