Taper or Roll [Archive] - Glock Talk

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SC_Dave
11-29-2012, 20:14
9mm FMJ

SHould I use a taper crimp of a roll crimp?
David

Taterhead
11-29-2012, 20:21
Taper... just enought to remove the bell without engraving the bullet.

JBnTX
11-29-2012, 20:33
Taper... just enought to remove the bell without engraving the bullet.

Correct answer.

freakshow10mm
11-29-2012, 22:56
Roll is for revolver.

Taper is for pistol.

fredj338
11-29-2012, 23:19
If someone is making a roll crimp die for the 9mm, that would be wrong. As far as I know, they are or all should be taper crimp.:dunno:

WiskyT
11-30-2012, 04:59
Did you read the instructions that came with your dies or the pistol ammo loading section in your reloading manual(s)?

Where would you even get a 9mm roll crimp die?

Fear Night
11-30-2012, 05:31
I don't think you are going to have a choice, you die is going to be Taper only.

GIockGuy24
11-30-2012, 05:49
Generally a roll crimp should only be used with bullets that have a cannelure. Most auto pistol bullets do not have a cannelure and a taper crimp should be used.

Colorado4Wheel
11-30-2012, 09:41
Some seating dies have a roll crimp built in even for 9mm.

http://www.midwayusa.com/product/255580/hornady-custom-grade-new-dimension-bullet-seater-die-9mm-luger-380-acp-38-super.

Pretty sure Lee does as well. I had a conversation with them about that a long time ago. But no link to prove it.

If you flare a reasonable amount and just remove the flare you can do the same basic thing with a roll or taper crimp die.

WeeWilly
11-30-2012, 09:54
As everyone has posted before, 9mm is a taper crimp.

Depending on the die manufacturer, for instance Lee, if you screw the crimp down far enough it will look like a roll crimp because they cut a step in the die body which is pretty steep. If you get a crimp that looks like a roll crimp with a 9mm die, you have the crimp screwed down too far.

The style of crimp is really not related to the style of action (pistol or revolver) but is based on how the round headspaces. Calibers that headspace on the case mouth require a taper crimp (most autoloading pistols, but not all). Rounds that headspace on a rim or shoulder can be roll crimped or taper crimped based on your needs.

SC_Dave
11-30-2012, 10:00
Did you read the instructions that came with your dies or the pistol ammo loading section in your reloading manual(s)?

Where would you even get a 9mm roll crimp die?

Yes I read it. No need to be rude, I'm learning like you once had to.

Here is where you get one:
http://www.midwayusa.com/product/255580/hornady-custom-grade-new-dimension-bullet-seater-die-9mm-luger-380-acp-38-super

SARDG
11-30-2012, 10:11
...Here is where you get one:
http://www.midwayusa.com/product/255580/hornady-custom-grade-new-dimension-bullet-seater-die-9mm-luger-380-acp-38-super
How could those rounds work correctly in a semi-auto? :dunno:

SC_Dave
11-30-2012, 10:14
How could those rounds work correctly in a semi-auto? :dunno:

I'm switching to a taper die now that I know more than when I posted this yesterday but they shot just fine in my Glock.
David

WeeWilly
11-30-2012, 10:14
The original 38 Super was a semi-rimmed case that headspaced on the rim, so a roll crimp was the original idea. Guys have gone to a rimless varient to aid in feeding and these require a taper crimp.

You can use a roll crimp die to taper crimp, you just don't screw it as far down.

judgecrater
11-30-2012, 11:23
Taper... just enought to remove the bell without engraving the bullet.
100% correct!

SC_Dave
11-30-2012, 12:02
Taper... just enought to remove the bell without engraving the bullet.

If the bullet spins in the case is the crimp too loose?

Fear Night
11-30-2012, 12:21
If the bullet spins in the case is the crimp too loose?
Yikes :wow:. The bullet shouldn't even be close to spinning in the case even with NO crimp whatsoever.

I think you are belling the cause mouth out way too much. It should only be enough that the bullet is barely able to "sit" on the mouth before seating.

SARDG
11-30-2012, 12:32
If the bullet spins in the case is the crimp too loose?

Yikes :wow:. The bullet shouldn't even be close to spinning in the case even with NO crimp whatsoever...
My 9mil loads with Dillon dies took on a 'Coke bottle' shape. Now, with a Redding Competition Die Set... not so much. Either way, the bullet was tight in the case prior to crimping. It isn't the job of the crimp to hold the bullet.

It sounds like over-belling which should also fatigue your brass faster and shorten its life.

Take a (very close) look and feel at a factory load to see (and feel) what your loads should look and feel like.

fredj338
11-30-2012, 12:35
If the bullet spins in the case is the crimp too loose?

Did you resize the case? That is impossible w/ a properly sized case, unless the bullets are undersized. Too much crimp can also spring the case mouth & allow the bullet to move. Even w/ over belling, there should still be adequate neck tension. If you are sizing the case properly & the bullets are the correct size (measure them) then check your expander dia. It should be no larger than 0.354".
If Lee is making their does w/ a roll crimp, then they are doing it wrong, what a surprise. You can sort of taper crimp w. a die like that, but it's sketchy. If you roll crimp, your extractor is liekly holding the round in place for sort of proper headspace, but it's not desireable.

SC_Dave
11-30-2012, 13:39
I took some of the bell out. Left just enough to hold the bullet in place for it to go through the crimp die. It seems to be much better though I am still using the roll die I have it backed off to the point it's just closing the case with no real crimp. I can't push, pull or spin the bullet by hand. Hornady 9th says an OAL of 1.1000 I'm at 1.1035 now.

I'm waiting on the taper die now.

Have patients with me guys, I'm learning.

fredj338
11-30-2012, 13:58
I took some of the bell out. Left just enough to hold the bullet in place for it to go through the crimp die. It seems to be much better though I am still using the roll die I have it backed off to the point it's just closing the case with no real crimp. I can't push, pull or spin the bullet by hand. Hornady 9th says an OAL of 1.1000 I'm at 1.1035 now.

I'm waiting on the taper die now.

Have patients with me guys, I'm learning.
SOmething to file away in your memory; OAL IS ALWAYS BULLET & GUN SPECIFIC. So even if you are using a Hornady bullet, you are not using their test platform. The bullet must fit, regardless of what the book says.

Noponer
11-30-2012, 13:58
How could those rounds work correctly in a semi-auto? :dunno:

Why not?

Autos do not actually headspace on the case mouth, but rather on the extractor claw. The case rarely (if ever) touches the front end of the chamber.

I am not advocating roll crimping auto rounds, but they would likely load & fire. Some shooters have "successfully" used .40 S&W rounds in 10mm guns... (not me! :supergrin:)

fredj338
11-30-2012, 13:59
Why not?

Autos do not actually headspace on the case mouth, but rather on the extractor claw. The case rarely (if ever) touches the front end of the chamber.

I am not advocating roll crimping auto rounds, but they would likely load & fire. Some shooters have "successfully" used .40 S&W rounds in 10mm guns... (not me! :supergrin:)

Well they actually do headspace on the case mouth. A properly fit extractor will hold the round in place but that is technically not where it headspaces.:dunno:

Taterhead
11-30-2012, 15:10
If the bullet spins in the case is the crimp too loose?

That is not a crimping problem. That is more likely a re-sizing problem where the neck of the case does not have sufficient tension on the bullet shank.

Noponer
12-02-2012, 13:43
Well they actually do headspace on the case mouth. A properly fit extractor will hold the round in place but that is technically not where it headspaces.:dunno:

OK, I used the wrong term. Yes... an auto does, by definition, "headspace" on the case mouth. But my comment was in answer to SARDG's asking how a roll crimp can work in an auto.

Even though an auto technically headspaces on the case mouth, the extractor holds the round away from the front of the chamber, so that the exact shape of the case mouth does not matter as far as position in the chamber goes (unless the case is too long).

As I said, some shooters use .40 S&W rounds in their 10mm guns without feeding problems. In those cases, a roll crimp certainly would not matter, as far as chambering the rounds go.

SARDG
12-02-2012, 14:05
Well they actually do headspace on the case mouth. A properly fit extractor will hold the round in place but that is technically not where it headspaces.:dunno:

OK, I used the wrong term. Yes... an auto does, by definition, "headspace" on the case mouth. But my comment was in answer to SARDG's asking how a roll crimp can work in an auto...

...As I said, some shooters use .40 S&W rounds in their 10mm guns without feeding problems. In those cases, a roll crimp certainly would not matter, as far as chambering the rounds go.
I think Fred's answer about how a roll crimp would work at all is the real answer - by having the extractor hold the round. I had little doubt that a roll-crimped 9 mil cartridge would feed and chamber into a Glock 9 mil barrel.

fredj338
12-02-2012, 14:24
OK, I used the wrong term. Yes... an auto does, by definition, "headspace" on the case mouth. But my comment was in answer to SARDG's asking how a roll crimp can work in an auto.

Even though an auto technically headspaces on the case mouth, the extractor holds the round away from the front of the chamber, so that the exact shape of the case mouth does not matter as far as position in the chamber goes (unless the case is too long).

As I said, some shooters use .40 S&W rounds in their 10mm guns without feeding problems. In those cases, a roll crimp certainly would not matter, as far as chambering the rounds go.
I have witnessed FT fire due to a worn extractor & over crimped rounds. SO while a properly fitting extractor does hold the round against the breech, I wouldn't want to count on it. Taper crimp your service pistol rounds for 100% reliability.

Colorado4Wheel
12-02-2012, 15:07
I am not advocating roll crimping auto rounds, but they would likely load & fire. Some shooters have "successfully" used .40 S&W rounds in 10mm guns... (not me! :supergrin:)

I have fired a 9mm in a 10mm. So yep. Works fine.

Noponer
12-02-2012, 15:20
I have fired a 9mm in a 10mm. So yep. Works fine.

Did you mean .40 instead of 9mm?

Or was that sarcasm? 9mm in a 10mm would blow the case every time.

Noponer
12-02-2012, 15:30
I have witnessed FT fire due to a worn extractor & over crimped rounds. SO while a properly fitting extractor does hold the round against the breech, I wouldn't want to count on it. Taper crimp your service pistol rounds for 100% reliability.

I never suggested that a roll crimp is OK... in fact, I said otherwise.

For the headspace to allow a good primer strike with a badly worn extractor, the case would have to be just the right length. Too short & the firing pin would not go deep enough. I never check case length, but have heard that most pistol cases actually shorten with multiple reloading vs. rifle cases which get longer. A friend said his measurements showed this.

Noponer
12-02-2012, 15:43
I think Fred's answer about how a roll crimp would work at all is the real answer - by having the extractor hold the round. I had little doubt that a roll-crimped 9 mil cartridge would feed and chamber into a Glock 9 mil barrel.

I did not think we were talking about feeding & chambering but, rather, primer ignition.

A 9mm will "feed & chamber" in a .40... & even fire. I have seen it while ROing at GSSF matches, & even ran a few 9mm rounds through my .40 Glock (back when I had one) for some experiments. Those I ran never failed to fire. Did not have much velocity & blew the case, of course.... and forget about any kind of accuracy. :whistling:

F106 Fan
12-02-2012, 16:33
Did you mean .40 instead of 9mm?

Or was that sarcasm? 9mm in a 10mm would blow the case every time.

Nah! They just bulge a little bit. I have shot a couple of 9mm in a .40.

The cases didn't fit the sizing die very well after that!

Richard

Colorado4Wheel
12-02-2012, 16:37
9mm in 10mm. Did not blow the case. Posted a picture in the past.

fredj338
12-02-2012, 18:30
I never suggested that a roll crimp is OK... in fact, I said otherwise.

For the headspace to allow a good primer strike with a badly worn extractor, the case would have to be just the right length. Too short & the firing pin would not go deep enough. I never check case length, but have heard that most pistol cases actually shorten with multiple reloading vs. rifle cases which get longer. A friend said his measurements showed this.
COrrect. Point, set your dies up properly, then regardless of the condition of the extractor, the round will fire. Roll crimping any servie pistol round is improper. Can you get a way with it, maybe, but why? Just set your dies up properly, no problems.:dunno:

Noponer
12-02-2012, 20:49
9mm in 10mm. Did not blow the case. Posted a picture in the past.

Yeah, I have fired 9mm in .40, too... it did not actually blow the case, that's true - but I would not describe the case as "a little bulged" as stated above.

I sure would not reuse such a case!