Hello .378 Wby owners !!

My question goes as follow; What perfect combination of bullet and powder have gotten the best performance,of you who owns this caliber ?

Another question is wether the recoil of a .338 RUM is worse than the .378 Wby (recoil velocity)?

Have any of you tried the .378 Wby with GS HV custom bullets ?

I would appreciate if any of you would give me some load data with 260 - 350 grain bullets ?!
Do you love or hate this cartridge, and why ?

Per577

The .378 kick guite a bit harder than a .338 Ultra in my opinion. I was reading that the .378 is the hardest kicking gun that you can shoulder because of no muzzle break.

I truely love mine, accuracy is outstanding.

I shot a 5/8" group @ 100 yards with H-4831 115 grains. Federal 215 primer and Hornaday bullets(270).
Muzzle velocity is 3180.

However, with the premium bullets made today I won't use Hornaday again. Few years back I shot a large Moose and the bullet came apart on impact.

If you go to reloading page or loadyourown.com you'll find some great information about some loads.

I never used the bullets you mentioned.
If I can help with anymore information please let me know. Good-Luck

Scratch

I had good results with hodgdon H4350 and 270 grain Hornady round nose and 235 Speers.
In my opinion the recoil without a muzzle brake is too much.Noticeably more than the 416/460WBY's I have had and prefer.
Put a muzzle brake on it and I assume it would be really great.
I had a 30-378 and it was a real pleasure to shoot with the factory muzzle brake on.
One thing that is really impressive with the 378 is the way it knockes down critters at short to very long range,very impressive.
Remember to have a scope with lots of eye relief,I put a 6x 42 Leupold on mine as it was a dual purpose rabbit,goat,pig gun.

Good luck,
Charlie

Hello!

Try 300 grs Trophy bonded ahead of 112 grs Norma MRP / RL-22 and Fed 215.
In my Wby this gives 2935 fts.
Very deadly on big game!! (Norwegian moose)

quote:

Another question is wether the recoil of a .338 RUM is worse than the .378 Wby (recoil velocity)?

Oh that was funny.

No I'm afraid the .378 has it beat handley.

Shooting 270 Hornady's at 3050 and 300 Noslers at 2960. They get your attention. But I'm only 5' 8" and it is not unmanageable. I wondered about that and had passed up a couple of pretty deals. Then I had a chance to shoot one. Weatherby was at a local range for a sportsman show and they had rifles available you could shoot. Bought a couple rounds and tried them out answered my question. A couple weeks later I ran across a very nice one for sale. Got a good deal on it. Barely used if you get my drift.

I own the RUM and Sammi says I can't go over 65000 PSI. What does Sammi say is the max for the 378?

quote:

I own the RUM and Sammi says I can't go over 65000 PSI. What does Sammi say is the max for the 378?

Recoil is the by product of bullet weight and total grains of powder more than chamber pressure. Does your Rum shoot 300 Gr. bullets using more than 107 Gr of 4831?

Now if you were talking 375 Ultra Mag you would be starting to get close but 338 Rum. Sorry son you've never shot a .378 Weatherby.

This may clear your mind and put things into perspective for you.

Recoil

My RUM shoots 300 gr bullets with 90 grs RL25 and they go 2750 fps. The PSI I'm Talking about is chamber pressure son I know it creates
recoil but each rifle has it limits and Sammi says 65000 is the limits for my RUM. What I asked was 'What is the PSI for the 378' that Sammi says.

JRO45 Did you click on the "Recoil" on my last post. Your RUM will come up in the list. It shows a recoil of 43.1 pounds. Then look down the chart .378 Weatherby 71.1 pounds recoil. You can read the formula on the page for reaching foot pounds of recoil. Tell me where Saami pressure is in that formula?

jro45

I just ran your latest figures for your gun through a Recoil calulator. Your now up to 55 pounds of recoil. Still a few ounces short. Get back to us with another load.

Recoil calculator

Many years ago I benched a .378 WBY with factory ammo for a Dentist friend. He was headed to AK for brown bear and wanted the zero checked as we found a few screws loose the neight before.
I shot four shots and felt something gritty in my mouth. I had lost a filling from a molar!! MAYBE it was due to fall out anyway...But still a great story on recoil!!

IF recoil is at ALL a concern.....look elsewhere. They .378 IMHO REALLY kicks. A world away from my .375 H&H.

FN in MT

Jay Johnson
The Rum can shoot to 3050FPS with the 250 gr bullet and still be within spects of what Sammi
says. So that chart isn't accurate.
Sammi PSI is Pounds Square Inch in the fireing chamber. It is what causes recoil. When a round is fired it creates pressure and the only way out is to push the bullet up the barrel And recoil come from how fast the bullet goes out the barrel. Different weight bullets can go at different FPS. And at different recoil. What I asked you was how much pessure can the chamber
of the 378 been tested to by Sammi. Sammi sets pressure limits for rifles so that way know one could blow their rifle up. And every rifle has a limit set by Sammi.

I spelled SAMMI Wrong its SAAMI. It is The SPORTING ARMS&AMMUNITION MANUFACTURES INSTITUTE.

If you don't know I wouldn't take a 378 to high pressure limits til I found out.

jro45
You haven't answered my questions and you are clueless.

The recoil calulator has nothing to do with my Question about the saami psi rating on the 378.
I've already stated what the RUM saami rating is

I'm not going to say things about you but if you don't understand what saami is just reread the posts. Causes it seems that you don't.

As far as recoil goes the RUM recoils alot less then the 378 does. 54 ft lbs of recoil for the 300gr bullet going 2750 fps and the 250 gr bullet recoils 50.59 going over 3000fps