Bullet swelling slightly?????

[oldracer]

This past winter I cast out about 200 total 0.451 500gn bullets for my Pedersoli Tryon, lubed them and put in a hardwood bullet holder. I have noticed the last two time I shot the gun, that accuracy has gone off the scale and the only thing that has changed has been the bullets. It seems they have swelled slightly going from 0.451 exactly when new to 0.452 now although some have stayed the same size? I borescoped the barrel and there was not lead build up and yesterday I did feel there is more resistance when both starting the bullet and when seating it down the barrel. I wipe between shots so that has not changed and the bullets are all the same batch of pure lead or as close as possible I guess.

So any ideas and does ANYONE have a .451 sizer die they could sell me as all sources seem to be out! Thank you.

[Omnivore]

Never heard of that one. The lead will age-harden, so the harder seating isn't too surprising. It's difficult to believe that one thou would make such a difference in a front stuffer, since the bullet is sized as it enters the muzzle (you already have a sizer - it's the barrel). The lead's hardness, on the other hand, might make some difference in accuracy.

I'd also be looking elsewhere - maybe at the muzzle, for dings. Also, when measuring soft lead, I suppose it would be possible to get a small reading as the caliper might flatten the soft lead slightly, depending on your technique. It might therefore appear, after the lead hardened, that it grew by one thou when in reality it didn't. Also oxidation and hardened lube might get in the way and make it appear larger... Just thinking aloud...

[oldracer]

Thanks for the info and I did find a .451 sizer die so I'll run the bullets through it when it shows up. I did check the muzzle and no dings or marks or scratches just inside the barrel? I did try lubed wads, non lubed wads (worked best) and lubed felt wads and the lubed felt was the worse and lubed fiber material was close behind. The bullets was kept in a hardwood plate so they do not get banged up and the lube is Doug Knoell's which is the same as I use in my 45-70 black powder cartridge guns which does not seem to dry out. The bullets do not have any nicks or roughness at the base as I check that at each load. So I'll keep looking I guess????

[mooman76]

Bullets do tend to grow abit after they are first cast by about a thous.

[NSB]

does the tool you're using to measure with measure in four decimal places or three?

[oldracer]

The micrometer measures to 4 decimal places and I zero it and check accuracy with a 0.5 gauge block left over from my nuclear power days as a machinist. I remember reading something in a couple Black Powder Cartridge Magazine articles about lead bullets changing but in my cartridges it was never noticed?

I have a 0.451 sizer coming so I'll see how they look after running them through the die. Any other ideas are surely welcome.

[groot nadine]

not knowing your definition of "off scale" I can only assume your hitting the proverbial side of a barn with you shots. For me, that almost always means sever leading in the barrel somewhere, somehow..

[oldracer]

Well I think I have the issue solved, at least until I make some brand new bullets. I ran the existing ones I made in January through a 0.451 sizer and there was a slight bit of rub on at least two sides, but not much. I went to the range today and tried a 70gn load with a plain wad and no powder compression and the bullet went through the right side of the 3 target backer when aiming at the center bull. The next show was with a lubed wad and the bullet hit the left side bull, both were tumbling. So I tried a lubed wad on the powder with a non lubed wad on top both seated slightly before putting the bullet down the barrel. Bang, about 1 inch to the right of the center of the center target! Wiped as usual and loaded the same, bang, about 1/2 inch to the left of the last shot. Wiped again and fired 3 more and all were within 1/2 inch of each other.

So it appears those English shooters are correct as the long range muzzle load website says most times TWO wads are required so that is what I'll use from now on.