Bullets Tumbling...

[SkyDyno]

Hi There.

My first post here so I apologise if it's in the wrong place....



I'm reloading .44 using a RL550b, Dillon size and power dies and a Lee seating and crimp die. I'm using Vihtavuori N320 powder, 240gr Lead SWC with 1.) 8.1gr powder and 2.) 6.0gr powder.

The pistol is a long barrelled Taurus .44 (Mod 66 ? - I'm in the UK so it's just referred to as a Taurus .44 LBR)

When using factory ammunition it shoots fine - what I expect from the gun and me.

When I use home loads the bullets tumble, going through the target sideways.. from 15 yrds out to 25. Distance doesn't seem to matter. Both 6gr and 8gr do the same.

The gun has been thoroughly cleaned and checked... no bulges etc. and the cylinder bores are as they should be. The fact it shoots fine with factory would suggest it's not the gun.

So.... I've tried:-

Changing the load - no difference.
Changing the crimp - no difference.
Checked the powder - good for purpose.

I've pushed a head down the barrel manually to get a sizing at the forcing cone. As far as I can tell the bullet measures .429/.430 - as it should be.

I could load using jacketed heads to try. I could change the bullet weight. I could change the powder...... heeeelp

But I'm at a loss as to where to look or what the problem might be.

So, over to the experts who can point me in the right direction and forgive my ignorance and stupidity if that's what it is... (after running away and hiding)

I look forwards to your suggestions and ideas....

Thanks.

[dromia]

Welcome!

How on earth did you manage to get your head down the forcing cone?

What you don't give is the key measurement, the diameter of the bullets. Tumbling is usually a function of too small a bullet and too hard an alloy.

The other situation is when the chamber is smaller than the groove diameters but if this was the case then it would happen with the factory as well, it sounds very much like the size quality of you bullet, is it home cast or commercial?

[WelshShooter]

Welcome to the forum. The projectiles are called bullets, and not heads. The head of a bullet is the underside of the brass case with the makers "headstamp".

Looking at the load data... Vihtavuori's website lists either a 240gr jacketed round with N320 but a starting load of 8.9gr to 9.7gr; or a 248gr Lead RNFP with N32C with a starting load of 7.6gr to 9.6gr. I'm assuming you've used the 240gr load data and 6gr and 8gr are lower than the starting loads. What made you choose these?

Your lead bullet should measure a couple of thousandth's over the bore size. If you slugged your bore as .429 then you should use a lead bullet of .431 or so.

[dodgyrog]

I would recommend a softer boolit sized to 430" and lubed with a soft(er) lube.

[SkyDyno]

Dromia thanks for your reply....

The bullet heads are commercial Hannam SWC 240gr heads labelled at .429 Dia. The random few I've checked do seem to be that.

I've had 10 rnds from some one else's reloads (200grn head though) but they did the same. The only thing I will say to that is I think the heads were from the same place, just a different weight. These heads do seem to be very hard compared to the factory magtech that I have, a fact that some one has mentioned now that I think of it.

It's driving me wild. If I can resolve the issue then I'll have to look for a different gun. I've had this one from new, It hasn't been abused or had hundreds of rounds through it...

[dromia]

Your lead bullet should measure a couple of thousandth's over the bore size. If you slugged your bore as .429 then you should use a lead bullet of .431 or so.

Your bullets should be a couple of thou over groove diameter not bore diameter unless of course the chamber diameter is smaller.

[WelshShooter]

Your lead bullet should measure a couple of thousandth's over the bore size. If you slugged your bore as .429 then you should use a lead bullet of .431 or so.

Your bullets should be a couple of thou over groove diameter not bore diameter unless of course the chamber diameter is smaller.

Oops, well spotted, my mistake

[dromia]

Dromia thanks for your reply....

The bullet heads are commercial Hannam SWC 240gr heads labelled at .429 Dia. The random few I've checked do seem to be that.

I've had 10 rnds from some one else's reloads (200grn head though) but they did the same. The only thing I will say to that is I think the heads were from the same place, just a different weight. These heads do seem to be very hard compared to the factory magtech that I have, a fact that some one has mentioned now that I think of it.

It's driving me wild. If I can resolve the issue then I'll have to look for a different gun. I've had this one from new, It hasn't been abused or had hundreds of rounds through it...

What are these heads you keep talking about?

I know Hannams sell hard cast bullets, is that what you mean?

If so then they sound too small and too hard.

You need to get a decent soft alloy bullet of a suitable diameter, as has been already said around 2 thou over groove, not bore diameter.

[SkyDyno]

Welcome to the forum. The projectiles are called bullets, and not heads. The head of a bullet is the underside of the brass case with the makers "headstamp".

Looking at the load data... Vihtavuori's website lists either a 240gr jacketed round with N320 but a starting load of 8.9gr to 9.7gr; or a 248gr Lead RNFP with N32C with a starting load of 7.6gr to 9.6gr. I'm assuming you've used the 240gr load data and 6gr and 8gr are lower than the starting loads. What made you choose these?

Your lead bullet should measure a couple of thousandth's over the bore size. If you slugged your bore as .429 then you should use a lead bullet of .431 or so.

Thanks for the info, I'll try to get it right next time.. saves on confusion...

That makes sense. Only slugged the bore this morning.

I started at 8 not wanting full magnum loads at present. On reading and conversation tried some a bit lower at 6 to see if there were any changes. None so back to 8.9

I would recommend a softer boolit sized to 430" and lubed with a soft(er) lube.

As above, makes sense. Now to find some and try....

[SkyDyno]

My apologies to all.....

Bullet is what I meant.

Consider your point made.