Hornady Taper Crimp Die Instructions

[pitted bore]

Well my Dad got me all confused.
He is telling me the seating die is also the crimp die
I am thinking the die that is just a taper to it is the crimp die because I ran a case all the way in it and the results were not good for my brass. Way undersized the case .

Just trying to figure it out due to me going to the range today with rounds we loaded last night and not being happy with the results

Keesey-
It's awkward to possibly get mixed up in a family disagreement. I'll give the standard explanation, and you can bounce it off your dad and see what happens.

The 450B cartridge headspaces on the mouth of the case. It's like most rimless auto pistol cartridges in this regard. As with those cartridges, a taper crimp secures the bullet in the case. The usual alternative to a taper crimp is the roll crimp, as used on most rimmed pistol cartridges; these headspace on the rim. Roll crimps should not be used on cartridges that headspace on the case mouth, because the roll crimp messes up the square corner at the mouth of the case. This can allow the cartridge to enter the chamber further than it was designed to do, producing excess headspace. Several bad results can happen.

For some unexplained reason, Hornady's 450B seating die is machined to allow a roll crimp to be applied to the seated bullet. This is not desirable. That's why I indicated in the 12 December post above, you should follow the instructions for seating without a crimp. (If Hornady intended for the roll crimp to be applied when seating, then why did they put a separate taper crimp die in the set?)

Now, if your Dad is used to working with RCBS dies and auto pistol cartridges, then he's likely correct. RCBS (and perhaps other mfrs, but I haven't checked) makes seating dies that apply a taper crimp to the 32 auto, 380 auto, 9mm Luger, 40 S&W, 10mm auto, and 45 ACP. Hornady's 450B seating die is not like those RCBS dies.

Hornady could, if they wished, make a seating die for the 450B that applies a taper crimp. They don't.

(Note: Yes, RCBS also furnishes roll crimp dies for the 45 ACP and 9mm Luger; the roll crimp is especially useful when reloading for revolvers that use these two cartridges. Also, some bullets for revolver cartridges work best when used with taper crimps, so RCBS makes taper crimp dies for the 357 and 44 mags.)

The mouth diameters of the 450B differ sufficiently from the 45 ACP so that the RCBS 45 ACP Seating/Taper crimp dies will not work with the 450B.

I hope this is clear, and that you and your Dad can come to an understanding of what's going on with the 450B.
--Bob

[pitted bore]

Hey Bad-Bob, can you pat your head and rub your tummy??

About that Oopsie, I have detonated cartridges that weren't supported at the base and the worst that happens is a slight pop, the bullet stays put and the case flies, say 5 or so feet. However, after saying that, don't do anything stupid and follow normal safety procedures..
..t

Tim-
I've read at least some of the literature on what happens to unsupported cartridges that go Bang, and your description is usually correct. But sometimes really bad things happen. I described such an event about three years ago on this forum. It can be repeated here appropriately, I think.

At a benchrest match a couple of decades ago, a shooter got a loaded case stuck in a bolt rifle chamber, and couldn't extract it. The extractor rode over the rim of the case. So he removed the bolt, cleared his bench, and took the rifle back to the cleaning bench to remove the stuck round. He inserted a cleaning rod into the bore and began to tap on the front of the cartridge to knock the case back out of the chamber. While he was doing this, the cartridge fired. Since it it unsupported from the rear, the cartridge case and primer ejected violently out the back of the action. Unfortunately, the shooter's wife was standing behind the rifle watching him. The case struck her in the abdomen. She died before they could get her to the hospital. The incident was written up in Rifle magazine. It's not clear how the cartridge could ignite when whacked on the tip of the bullet, but it happened, and there have been other similar incidents.

Be careful.

--Bob

[wildcatter]

Hey Bad-Bob, can you pat your head and rub your tummy??

About that Oopsie, I have detonated cartridges that weren't supported at the base and the worst that happens is a slight pop, the bullet stays put and the case flies, say 5 or so feet. However, after saying that, don't do anything stupid and follow normal safety procedures..
..t

Tim-
I've read at least some of the literature on what happens to unsupported cartridges that go Bang, and your description is usually correct. But sometimes really bad things happen. I described such an event about three years ago on this forum. It can be repeated here appropriately, I think.

At a benchrest match a couple of decades ago, a shooter got a loaded case stuck in a bolt rifle chamber, and couldn't extract it. The extractor rode over the rim of the case. So he removed the bolt, cleared his bench, and took the rifle back to the cleaning bench to remove the stuck round. He inserted a cleaning rod into the bore and began to tap on the front of the cartridge to knock the case back out of the chamber. While he was doing this, the cartridge fired. Since it it unsupported from the rear, the cartridge case and primer ejected violently out the back of the action. Unfortunately, the shooter's wife was standing behind the rifle watching him. The case struck her in the abdomen. She died before they could get her to the hospital. The incident was written up in Rifle magazine. It's not clear how the cartridge could ignite when whacked on the tip of the bullet, but it happened, and there have been other similar incidents.

Be careful.

--Bob

Oops, but then that was a supported case, although a poorly supported case, but supported enough to do real damage. If you take a 2 or so inch pipe, long enough to cross over an open-top fifty five gal drum, placing any cartridge into the middle of the pipe, lighting your trash on fire, under the pipe, you will soon see my description. The bullet stays in the pipe, the case leaves the pipe, say 5 or so feet. Now, you guys, this is a conversation between me and Bobber, two old-timey pros. Some might say two pros, talking out their butts and they'd prolly be correct.

If you try any of this at home you can expect the results Bob described, and death might be the easy way out, get it??

..t

[Jim in Houston]

SAAMI has produced a video that looks at the performance of unsupported sporting ammunition under various scenarios, including fire, falling from height during transportation or storage, and being shot, among others. As a general conclusion the risk from unsupported ammuntion in these scenarios is very low. Of particular interest to me, is the impact of packaged ammunition subjected to fire, which is addressed at about minute 13 in the video. Basically, none of the thousands of rounds of ammunition that were fully engaged in the diesel fueled fire completely penetrated both layers of a standard sheetrock interior house wall, although a very few went through the first layer of sheetrock. They also posed no hazard to exposed firefighters in their full fire fighting kit, including face shield. This fire test was repeated under various conditions with similar, low risk results.

The video is at http://www.youtube.com/watch?v=3SlOXowwC4c&list=UUiWxn1eVlnOQ8sZQqLL-ijQ.

[wildcatter]

This is actually interesting. I've seen those sammi flicks and I have burned a pile of 22lr's myself, had one that got stuck by a log. All of them just fizzled, the one that got stuck, actually went POP, flew a hundred yards or so and broke a window.

So, the deal is, we can't trust what is going to happen, in a fire. For the most part, nothing will happen, of any consequence, but the watch phrase here is "for the most part". In other words, you prolly would be OK or maybe you'll end up as the women that PB described..

..t

[Keesey]

Well went back to playing with the crimp die today. Pops and me had a hard time measuring the crimp with mics and calipers. All we could get was .480 and .478 never able to get 476 as mentioned around here, so I kept adjusting it down with the bullet seater backed all the way up and never got a change until I buckled the case

[PRKL8R]

Keesey: My taper crimp die does not have the bullet seater in it. The roll crimp is in the bullet seating die. The taper crimp die was a sepperate die, hollow all the way through. At least that is how it is in my Hornady's. Try that die if you have it. So far I've had no problems acheiving .476 crimps

[Keesey]

There was four dies in my set

Primer/sizer
Bullet seat/ crimp I thought
Necker
And the open center die


None where labeled and I thought the crimp was in the seating die

[wildcatter]

Keesey: My taper crimp die does not have the bullet seater in it. The roll crimp is in the bullet seating die. The taper crimp die was a sepperate die, hollow all the way through. At least that is how it is in my Hornady's. Try that die if you have it. So far I've had no problems acheiving .476 crimps

Good Call and the roll crimp is entirely the wrong crimp. Sorry about this, but if you've been using a roll crimp, you will have to pull those bullets and re-crimp with the taper crimp or very bad things can happen!!

..t

[Hoot]

Good Call and the roll crimp is entirely the wrong crimp. Sorry about this, but if you've been using a roll crimp, you will have to pull those bullets and re-crimp with the taper crimp or very bad things can happen!!
..t

From the Hornady web site!!!!!



I guess they wait for the first fatality before they spend the money to correct their mistakes.

Hoot