Home Forums Hunting & Shooting Express Rifles and Big Bores Only .378 Weatherby

Does anyone load for the .378?
I have a U.S made Euromark and looking for suggested starting loads for the 300gr Accubond.

Thanks!

Hello Boomer,

Nosler does not show a 300 gr. Accubond in the current #6 manual for any .375 cal. They do show the 300 gr. Partition bullet. The only Accubond for .375 is 260 gr.

Steve

That's a nice rifle. Why not visit the hogdon site and pick one of the 300 gr bullet starter loads?

http://data.hodgdon.com/main_menu.asp

If you're not looking for maximum punishment, selecting a safe starter load should be easy.

My bad...I was thinking or not and looking at 340 mag. Yeah go to Hodgdon....its late

102gn H 4831 with 300gn Swift A-Frama for 2650fps (mild easy shooting load)
111gn Rel 22 for factory specs around 2930fps
113gn Rel 22 for MAX and just over 3000 fps.

The 4350 work well with the lighter bullets as does H4831

Reduce loads 5% and work up please.

JW

Many thanks for the load suggestions.
The thought of a 300gr at 3000fps is exciting

Ian

I use a 375 H&H for NA bears but traded a few years back for a German Mark V in 378 Weatherby with a Pendleton brake,,,in case I one day made a trip to Africa for Cape Buffalo...I have read a lot about this caliber but no experience with it...what combos do you 378 users recommend?? In my 375 I use the 275 Bitterroots and WW 760 with Federal 215s in WW cases...I have read in Hagels writings the Norma/Weatherby is softer than Winchester...any comments??

I only have a .375 Wby, but if I had a .378 Wby, I would really want to try out the 350gr TSX, which has a B.C. of 0.425. I assume you could get about 2,700-2,800 fps out of it out of a .378, which would be pretty wicked against really big things.

Thanks...I think you are right on target with your velocity...102 H4831 shows to be 2779 to 2653 in Hodgdon and Barnes manuals....I think I'll get to work with the 350 TSX and see what happens...

The 378 is a superb caliber and like all weatherby calibers, they "outran" bullet technology at the time. I can't remember how many times I've heard (or read) "Weatherby calibers spoil too much meat, don't penetrate etc." All true thirty years ago maybe. With today's super-premiums like the TSXs the 378 is an incredible killer far out-pacing the 375s. Recoil is pretty stiff though. It comes back very fast and you need to hold on, but th result on game is devastating.

This is the albiet limited data I haev acrued using 2 different .378's.

JW


Bullet Load Powder O. A. L. Velocity Energy Comments

220gn Hornady 114gn IMR 4350 3380 5582

235gn Speer 112gn IMR 4350 3336

270gn Hornady 115gn H 4831 3142 AR 2213 used
117gn H 4831 3178 6057 AR 2213 used
117gn H 4831 2998 Original Surplus Powder
108gn IMR 4350 3150

300gn Hornady RN 102gn H 4831 2650 AR 2213 used

300gn Swift A-Frame 111gn Rel 22 2928
113gn Rel 22 3006 Warm Load


AR 2213 is H 4831
NOTE: that teh Origianl Surplus 4831 is designated separately.

Because the tSX essentially at worst turns into a solid no matter what happens to the expaonding front, that 350gr at 2,750 or so would be good, IMO, at the least, on any game not exceeding 3,000 lbs--and maybe more.

If you sight that in 3" high at 100 yds, it's only 5-1/4" low at 300 yds and has the same kinetic energy at that range as a 300 Win Mag does at the muzzle.

Wicked.

FWIW, I get 2,830 fps out of the 300gr NP loads in my .375 Wby. But it weighs about 11.5 lbs including a mercury tube in my MkV DGR. It recoils less than my Rem 700 .300 Win Mag. It's a bit hefty, but I;m in shape enough to carry it.

The 350gr out of the .378 Wby seems like an almost-unbeatable combination of speed, weight, mass, and down-range ballistics.

thanks for all the input re: 378 Weatherby...anyone use the Hawk 350 for NA hunting??

Load lightly.LOL
I had two buddies that had/have 378s and their shooting deteriorated conciderably compared to before they had them.
One fellow got a muzzle brake and that helped but the blast from it was terrible while hunting.
My question is can a 378 be loaded down to 375 H&H level without having to worry about hangfires? The 378 is nice but I would want one only if it could be loaded down.

This is a load only 100 fps more than the same bullet loaded in the .375 Wby, which is very pleasant to fire in my 11.5 lb .375 Wby DGR rifle. Weight makes a difference. I would not hesitate to man up and carry around and shoot a 11-12 lb Mk V .375 Wby, but I would rather drive nails into my forehead than fire a 7.5 lb .378 Wby.

Yep, that's why I sold the 378 and kept my 375Wby

Had a buddy who shot three scopes off his 378. He finally put a brake on it, but you did NOT want to be standing anywhere near when he touched it off.

I used to also own a non-braked 378 and the recoil could be described as very fast and if you had your eye too close to the scope it would have drawn blood for sure.

Boomer - Curious if you kept the rifle -- and if you still had any friends left if they stood next to the muzzle brake when you fired?

Mike378 owns 4 custom shop .378's. He is the Grand Poobah with this cartridghe as I know he owned at lease 2 more before these beauties arrived.

JW