Projectile Questions and Anwsers for Newbies

Yes the Hornady does seat and crimp at the same time with a taper crimp and I thought I had it set but when I started to lower the bullet after crimping, the die had a death grip on the bullet case and I thought it was stuck up into the die causing me to apply a lot of force to get it back out, I knew then something wasn't right! These dies are not supposed to need lube but it sure felt like it did.

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1. Hornady gives you a roll crimp in its 45 Colt seater die, not a taper crimp. (You can see the roll in your picture)
2. Seater dies do not need lube. You got stuck as result of trying to jam the case mouth -- not into the crimp goove, but into the bullet lead itself.

Again:
-- Unscrew the seater die so that it doesn't crimp at all.
-- Then seat all bullets to where the case mouth does not go past the top of the crimp groove. (See WalkAlong's photo above)
-- Unscrew the seating stem at least 1/4" and screw the seater die contacts the case mouth -- then 1/2 - 2/3 turn more.
-- NOW crimp all cartridges. It should roll the case mouth smoothly into the groove.

Again, do it in two distinct steps at this stage:

- (With the seating die body unscrewed off case contact) Seat bullet only to the top of the crimp groove -- not beyond.
- THEN crimp with the die body screwed down, but with the seating stem unscrewed.

Roll crimp. Revolvers get a roll crimp, semi-autos get a taper crimp.

A quick primer on lead bullets:

Three things effect potential leading in barrels.

1. Bullet Diameter
2. Bullet Hardness
3. Lubricant

With cast bullets, you want to size a bullet so that it is one or two thousandths larger than the bore diameter. To determine the bore diameter you can force a cast bullet through your barrel, and measure it. In revolvers, you have to check each cylinder throat as well.

Bullet hardness is more alchemy than science. Two hard and the bullet won't expand to seal the bore, letting hot plasma slip by. This will cause leading. Too soft, and the gasses will cause the tail end of the bullet to solder the inside of the barrel. The higher the pressure, (not speed related necessarily), the harder the bullet you want.

Lubricants can help prevent leading even if the above two things are not exactly right. Softer lubricants work better than hard lubricants. Commercially cast bullets typically use harder lubricants so they will survive shipping. For this reason, they carefully size every bullet, and use a harder alloy.



The main reason I typed all of that for you is the picture you posted of your first attempt.
It is my opinion that you have too much crimp on that bullet. If you put too much crimp on a bullet, it can re-size the bullet when fired. This can cause a now too small bullet to lead a bore.
So: Go easy on the crimp. You appear to have plenty of neck tension to hold the bullet anyways.
Try seating a bullet without a crimp. Push it against a solid surface. If it takes a lot of force to get the bullet to move, (yes I know it's subjective), then you probably don't need any crimp.
If the bullet moves relatively easily, add a bit of crimp until it does not. That is all the crimp you need.

In automatics the problem with bullets moving is called 'bullet set back', where the bullet ends up too deep in the case. This reduces usable case volume, and with max loads has the potential to cause a kaboom.

With revolvers, the problem is just the opposite. Recoil from previously fired rounds can cause the bullet to pull out of the case, causing the tip of the bullet to protrude from the cylinder face, and jam the gun. This will cause much cursing, frustration, and flailing of arms, but no kaboom.


I hope this helps a bit.

Bullet hardness is more alchemy than science. Two hard and the bullet won't expand to seal the bore, letting hot plasma slip by. This will cause leading. Too soft, and the gasses will cause the tail end of the bullet to solder the inside of the barrel. The higher the pressure, (not speed related necessarily), the harder the bullet you want.

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Alls fair, but it is actually a science. Sad, I know. No rivers of Galena, No mermaids, no hocus pocus.

Pretty good math on it in the lyman cast bullet handbook if you are so inclined. IF not, the pressure/hardness requirement conversion table can be found with a simple search.

Or...

Optimum BHN = CUP / (1422 x .90)

That little equation solves about 90% of the problems. It's the other 10% that get might close to witchcraft to solve.


I agree the original crimp attempt was a little aggressive, but it sounds like he's fixing it !

BHN is in pressure (psi) units.
So use psi in the equation (not CUP)