To the group

I am in the process of putting together a 340 Weatherby rifle. I'd like to use a Winchester Model 70 controlled round feed action. I put together a 300 H&H a while back using a 300 Weatherby length action. At this point I'm finding it very difficult to find a suitable donor action since the 300 Weatherby actions, 7 mm shooting times Western actions and the ultra mag actions are becoming more and more difficult to find as well as expensive. Does anybody have any suggestions regarding, how much machining would be involved in converting a 7 mm magnum action into a full length action that could accommodate a 340 Weatherby length cartridge. I'm just trying to decide what would be the most economical route and at this point it seems like the difference is becoming greater between buying a standard magnum action and a full-length magnum action. Any helpful thoughts would be greatly appreciated

Thanks

Brad

Tip Burns put a .340 weatherby barrel on a m70 push feed for me last year...after I was given a .340 weatherby barrel and quite a bit of factory ammunition and brass.... the barrel had started out as a .338 win mag, then had extensive work done on it, including rechambering, a shroud over the full length of the barrel and a muzzle brake... I used a 7 rem mag rifle as a donor.... AFAIK, he changed the magazine box, and bolt stop.... it feeds great, and will unload factory length cartridges....you might pm tip and ask him... he still posts here, even tho he's closed his shop....

I've turned a number of 7rem mags to STWs. Take out the mag spacer and use a longer follower. Shorten the bolt stop and ejector and you are done. Easier yet if you can find the parts. The ejection port can be lengthened but it will work fine as it is.

Follow on Question:

So if I started with a standard classic Mod 70 in 338 Win Mag I assume it could be turned into a 340 weatherby with the above mentioned modications?
Brad

quote:

So if I started with a standard classic Mod 70 in 338 Win Mag I assume it could be turned into a 340 weatherby with the above mentioned modications

yep



If you can find the long action mag box, follower, bolt stop and ejector then you swap and rechamber. If not the stop, ejector are shortened the spacer removed from the rear of the mag box. I never tried using the shorter follower but a long one should be easy to find.

A wby reamer will clean a 338wmag chamber.

The follower might work as is; at least I used the same follower when I converted a 7 mag to a 338 RUM. You don't need any new parts; just alter the ones you have. This is not a hard conversion; you can do yourself if you can remove the barrel and have a lathe.