Hi y'all!

I've been reloading blackpowder cartridges for my Contender G2 with 23"bbl. I'm using 520gr flatnose bullets cast from pure lead, using a Redding double cavity mould.
The problem is this: although the bullet seems to be accurate, after 2 or 3 rounds I cannot chamber any cartridges anymore. The bullet -after trying to chamber a round- always shows severe markings from the rifling. I have tried other powders (Elephant and Swiss No2), and although my bore seems to foul up a lot less, the problem persists.
I can only come to the conclusion that the 23" .45-70 bbl does not like this bullet. (I have tried 350gr bullets from a RCBS mould, and 330gr HP-bullets from a Lyman mould, and cartridges with these chamber just fine.)

The thing is, I want to use a heavier bullet than these 330 and 350gr ones. Preferrably a bullet that weighs 500gr, for use at longer distances.
Does anyone know of a bullet mould which bullets will seat fine in a Thompson/Center Arms 23" .45-70 barrel?

(Forgot to mention: I just LOVE the .45-70 BP cartridge!)

If your cartridges load easy for the first 2 or 3 rounds it sounds like the chamber is building up with black powder fouling. Try using a wet patch between shots to loosen up the black powder residue. Don't leave it wet it will cause it to rust.

Max

When you step over from smokeless to black powder you almost have to throw everything you have learned about reloading out the door.

Your shooting a modern rifle designed for smokeless powder, so the rules have changed.

First i would not shoot a bullet made from pure lead, its going to lead your bore, then your accuracy will go south.

I would shoot one with some tin in it or shoot straight wheel weights, the seceret to shooting wheel weights with black powder is to shoot it as close to bore diameter or a little over.

I shoot a 1885 winchester in 40/65, i shoot a 400 grain snover bullet sized to .410, the bore measures .408, i use SPG lube on the bullet and i also use a walter's wad under the bullet.

I use swiss powder cartridge grade, and i compress it .40, you have to compress black powder to make it burn right, with elephant and Goex you will have to compress lots more.

You also need to be sure and clean your cases really good, the powder fouling can build up in the neck area and make seating a bullet harder, i use a mixture of 1 part water 1 part simple green, 1 part murphys oil soap, i put them into a plastic container and shake around some to help loosen the fouling, then rense off with cool water and lay on a towel to dry, then tumble to polish.

You didnt tell us about the way your reloading or the kind of lube your useing on your bullets, this is very important, if your useing a hard lube it wont keep the black powder fouling soft enough for you to get another shell in after shooting a couple of rounds, i hope this has helped some, if you need more info ill be glad to help you all i can, i love the 45/70 also, and as for black powder well if you ever get into shooting it for very long your hooked, have fun be safe, Bubba.

Once fired, I do not resize the cases. I just punch out the spent primers, and clean them in hot soapy water.
As said, I cast my bullets from pure lead, although in my last batch I have mixed up about 5% tin in it.
I use my bullets as-cast, and pan lube them with a mix of 50-50 beeswax/molykote BR2 Plus. The bullets are just pushed inside the unsized case, with the lube "glueing it in place". No crimp is used.

For the last batch, I weighed 65 grains of Swiss No2, and used the RCBS 350gr flatnose. I think it's a potent cartridge that way for up to 100 yards or so, and the rounds chamber just fine, even in a dirty barrel. Recoil is lovely, and the cases come out bright and shiny.
(The thing is: a buddy of mine gave me these bullets, but he's sold the mold years ago. He said he thinks it was an RCBS block, but he isn't sure. I have about 20 bullets left...)

The Redding 520 grainer interests me for longer range shots. It fits the bore just fine, I can even slide it's nose section in the muzzle when the barrel is still clean. After only 2 or 3 shots, the fouling prevents that...I then cannot even chamber a cartridge anymore unless I pound it in. Inspection of a partly chambered round learns that the bullet is marked by the rifling. A large part of its nose is riding the bore, and a TCA G2 has only a short throat, which means that that long nose section is sitting in the rifling for at least 1/4 inch. This Redding bullet, therefore, may not be that suited for my rifle.
So I'm searching for a heavy bullet with less bore ride length than the Redding has. About 10/16" of the bullet can be in the case, or else I cannot get the 65grs of powder in it.

Ever consider using a blow tube?

Well, to be honest: untill only a couple of days ago I didn't even know what a blowtube is.
But I made me one, and I'm goint to try it shortly.

That should keep the fouling soft, if tempature goes up or humidity goes down, blow more times.