Weird off set sizing issue

[CLP]

Mould is a Lee 430-310-RF, alloy is 96Pb3Sb1Sn. Hornady gas checks.

I cast some to work up a load and chrony them. Using a RCBS Lubrisizer. Lyman sizing die- .430. Now the top punch I used was whichever one is used for Lyman's 44cal Devastator. That one had the best fit of the two I had, and you can see that it beveled the meplat. Using some 'ol all purpose blue RCBS lube.

Now here's where it gets weird. As I start sizing these bullets I notice that the front driving band starts getting a taller on one side of the bullet. It's minor, so I don't give it much thought at first. Possibly a soft bullet that doesn't harden evenly? No, it's progressive. And it progressively worsens as you can see by the photos. I rotated the bullets 180 degrees so that you can see how it's affecting only one side of the bullet. To the point that the one side is squashed to the point of a mirror like finish and the loss of the lube and crimp grooves.

What gives? Anybody have any idea what might be causing this? Appreciate your help! Thanks

PS- I'm also posting this on Castboolits to see if anyone there knows what's going on.

 

[wmurphy]

Looks like possibly the wrong top punch. Although the size/shape of the top punch needs to be close to that of the bullet, it needs to apply pressure on the very top of bullet. Looks like the bullet is being pushed by the sides causing the bullet not to go into the sizer straight.

 

[rcmodel]

I agree.

Your top punch doesn't match the bullet ogive shape.

So it is getting pushed into the die crooked.

Any time you see nose deformation like those, you have the wrong top punch for that bullet design.

rc

 

[CLP]

That's what was suggested at castboolits. I was quick to disagree at first, having second thoughts now that I'm getting similar remarks here.
But look- if it was being caused by the top punch sizing it crookedly, then I would expect two things:
1. It wouldn't be a consistently progressive off-set sizing. They started off sizing normally. No noticeable problems at all. Then it became noticeable. Then more pronounced. Then markedly off set. It is a unidirectional problem. I would expect the sizing variation to have a range of sizing error if it was being caused by an improper top punch sizing them at various angles.
2. I would also expect variations in the beveling the top punch left at the meplat. But the bevel was consistent. It was the same between the early bullets that sized normally and the latter bullets that were distinctly squished on one side. You can't tell a difference between the two.

Are there any other possible explanations?

 

[rcmodel]

Take the top punch out and make sure it doesn't have a bunch of lead frags stuck in it.

The 1st. On the left shows none, just a ring where the top punch doesn't fit the bullet correctly.
The 2nd, shows more galling.
Your 3rd. Bullet on the right clearly shows a lot of galled lead on the sides of the ogive.

There must be some stuck in the top-punch too.

rc

 

[243winxb]

As cast diameter to big. Sizing down more than .003" may deform the bullets.

 

[CLP]

Cast diameter 0.43005 to 0.431. Sizing a thou or less.

Top punch was clean.

There was plenty of lube in the reservoir.

However, the sizing die was of interest. I'll have to get a picture up later. I'm heating it up so I can push the sizing die "rod" out to inspect it further. That RCBS blue lube is like glue when room temp. Anyway, the bottom of that rod has some gouges from something, about four of them, one at least a quarter of an inch long. Maybe they're a couple thou deep. Rubbing against something I'd think. COuld there have been grit in the reservoir or lube that couldve gotten in there? The die is ruined I'd imagine.

 

[243winxb]

Grit in the reservoir*may be possible from a new sizer. RCBS lube melts at 115 degrees. If the die was binding, it would require heavy pressure on the bullet, deforming it.

 

[243winxb]

What was the fix, if you found one?

 

[CLP]

Sorry, I haven't gotten back down to the basement. Real life intervened and I've had my nose to the grindstone. I'll get pics of the scratched up die/rod. I think with that particular bullets meplat the best solution is a flat bottomed top punch.

 

[CLP]

The scratched up rod in the die. It should be nice and shiny. Whatever was in there was the cause. Even after warming up the die to soften the wax, it's wedged in and I can't get it out.

 

[243winxb]

Good to know. Ty.