.375 Weatherby cast bullet OAL issue (?)

[rp85]

.
Good morning;

Purchased a .375 Weatherby to shoot nothing but cast bullets. Rifle is a R\H Sako converted to left hand and a custom 26.5” barrel. Original owner passed 50 years ago and has not been shot sense his passing.

No idea on manufacture of barrel. Have not fired this rifle yet.

Lyman cast book list OAL for the Lyman 375248 cast bullet as .3.395”. Cannot close bolt until the this bullets OAL is 3.275”

Do I have a problem with this OAL? Thanks for any input.

rp

UPDATE; very possible rifle has a short chamber. commercial manufactured gas check lead bullet, 280 gr., when attempting to seat bullet almost the entire bullet goes to case. Now what?
open to any suggestions. thx again for any input.

rp

[Nobade]

No, you have a good thing. The normal Weatherby chamber should have about 3/4 inch of freebore and yours, since it's custom, doesn't. That is a really good thing for cast bullet accuracy. Congratulations!

Just watch it if you ever fire a full loaded cartridge in that rifle though. You may run into pressure problems since that freebore is there to allow cartridges that are loaded to too high pressure (Weatherby factory ammo) to function properly.

[15meter]

Never have loaded for that cartridge, this a guess that the bullet nose is too fat.

Is there such a thing as a bore riding 375? That may be what you need.

I ran into the same thing with a couple of rifles chambered in 416 Rigby. All the standard .416 boolits would telescope into the case upon loading. I ended up with a custom Accurate mold with a long tapered nose to both feed and chamber.

I sent a .416 solid that had been pulled from a cartridge that fed perfectly every time and had that profile duplicated.

Those two rifles gave me fits trying to get ammo to feed and chamber. One a factory Ruger, the second was a custom rifle built on a magnum length single square bridge action. Fed bullets with no problem.

Cast not so much. Until the right boolit profile came along.

[Winger Ed.]

If the bolt has resistance but isn't really hard to close is sort of normal for some boolit designs.
They are supposed to lightly engrave some rifling marks on the boolit.

[Nobade]

Just to be sure, look at it with a bore scope or do a chamber cast. It's always good to know what you're working with so you know how to proceed. I have seen custom barrels cut with no throat at all, or even a bevel on the rifling. If that's the case you'll need to have it fixed. All else fails, load a few rounds like you want and have a gunsmith throat it to match.

[Larry Gibson]

No, you have a good thing. The normal Weatherby chamber should have about 3/4 inch of freebore and yours, since it's custom, doesn't. That is a really good thing for cast bullet accuracy. Congratulations!

Just watch it if you ever fire a full loaded cartridge in that rifle though. You may run into pressure problems since that freebore is there to allow cartridges that are loaded to too high pressure (Weatherby factory ammo) to function properly.

What Nobade said^^^^^