30-378 Weatherby

Elkheart

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Joined
Dec 31, 2016
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15
Finally pulled the trigger on new 30-378 Weatherby. Have a 300 Weatherby Mark V that I've killed a lot of elk with. I've been wanting the 30-378 for some time now. Set up will be 30-378 Accumark, Near Manufacturing rail and scope rings, Swaro x5i 3.5-18x50, and Javelin bipod. Waiting on brass and bullets to arrive. Will be testing out Berger 215 and 230 hybrids loaded with H1000, Retumbo, and IMR 8133 to see which one performs the best. Have Redding sizing die and Foster ultra micrometer seater. Will post some results as soon as everything comes in and can get some loads worked up. Cheers
 
I just did one with the 215 and Hodgdon 50BMG. I wasn't real impressed with the speed (2925), but it shot GREAT.

I took the advice of the guys in the know from this website......

1) the 215 is a very well proven killer.
2) The 1-10 twist may be a tad slow for optimum performence with the 230.

Good luck, and don't forget your hearing protectors!!!

Tod
 
Elkheart, looks like you off to a great start. Mine shoots most accurate with Retumbo and the 215 Berger. My brother in law's likes H1000. I tried H1000, but the Retumbo is a bit faster and accurate. This is with a bedded stock and a tuned trigger by a gunsmith. Note: brother in law first bought Hornady brass and the primer pockets were loose after 1-2 firings. Go with Weatherby/Norma brass. Good luck
 
Elkheart. Great rifle and a little ignored!

I had to get mine worked on. New trigger, stock, bedded, barrels, brake and then it grouped less than .5 MOA. Shot 6" groups at 1000yds with SMK 240. Used this also for elk. It did not like 210 Berger as much and I ve not tried 230 but on my next reloading plan. 94 gr Retumbo. I use 200 TSX for Africa plains. Instant drops!
 
I have a HS Precision LRH chambered in 30-378 Wby, it loves 200 gr. Barnes LRX and 105 gr. H Retumbo at 3127 fps. I've shot several 1 inch groups at 300 yards, and have killed a Moose and a Brown Bear in Alaska. It really puts the hurt those big animals, with that big case I really like the tougher bullet that Barnes makes.
 
I learned about overbore reloads with my .257 Weatherby Mag. If given the PROPER powder, the 30-378 will walk all over the .300 UM. With the heavier bullets, it will really walk over the .300 UM. In a situation like this we are talking 200 FPS or so. Which is really meaningless but if anyone wants to use that against me, then you are beat again, as the .300 WM is as good as anything and more accurate on average than all the rest. Just food for thought. I'd never even look at Lazzeroni as they are too small a company. Maybe if I could handload to their numbers. My options are .300 WM and 30-378 Weatherby Mag. if more is needed.
 
Depending on the length of your barrel, H 5010 used to be my favorite powder. with it being discontinued i had to go to H 50 BMG. Have yet to try Vit N 570 but it works great in my 30 Texan. I use 200 grain bullets and get over 3300 ft/sec without pressure signs.

Something in the neighborhood of 117 grains gave great accuracy (.092
5 shot 100 yards and .897 at 300 yards).

With the SAMMI freebore of the 30-378 there is more powder capacity
than can be used, and with more slow burning powder, all that is gained is muzzle flash.

J E CUSTOM
 
Depending on the length of your barrel, H 5010 used to be my favorite powder. with it being discontinued i had to go to H 50 BMG. Have yet to try Vit N 570 but it works great in my 30 Texan. I use 200 grain bullets and get over 3300 ft/sec without pressure signs.

Something in the neighborhood of 117 grains gave great accuracy (.092
5 shot 100 yards and .897 at 300 yards).

With the SAMMI freebore of the 30-378 there is more powder capacity
than can be used, and with more slow burning powder, all that is gained is muzzle flash.

J E CUSTOM
Wow.......117!! We hit a little PSI at 110 of 50 BMG and enough to make me quit at 111 with the 215 Berger last week. Again settled at 108. The other's were about the same if my memory servs me right. NONE were speed monsters.

LOTS of drama when you touch one off!!!:D
 
Never really understand the 30-378. If I need more hp than the other 300 mags, I'm moving to a larger caliber. The whole diminishing returns shows here. BUT I hope you have a great time with it.
 
Wow.......117!! We hit a little PSI at 110 of 50 BMG and enough to make me quit at 111 with the 215 Berger last week. Again settled at 108. The other's were about the same if my memory servs me right. NONE were speed monsters.

LOTS of drama when you touch one off!!!:D


I have the SAMMI freebore for the 378 case and this allows me to load a little hotter. Also I am using the 200 grain bullets for maximum powder capacity. I tested all the way to 122 grains but found very little increase in velocity with the 28" barrel.

This was also using H5010 and the best load so far is 114 grains of 50 BMG. Caution should be used when loading this cartridge, because there are many different variations in free bore and throat dimensions.

I have re chambered several that the owners had taken
liberties and changed neck diameters and shortened free bore to get close to the lands. These chambers will not tolerate factory loads and normally blow the primers.

J E CUSTOM
 
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Never really understand the 30-378. If I need more hp than the other 300 mags, I'm moving to a larger caliber. The whole diminishing returns shows here. BUT I hope you have a great time with it.

I get what you're saying about the super mag 30's that said I've been way happier with my 300AX in comparison to my 338LM.
 
Finally pulled the trigger on new 30-378 Weatherby. Have a 300 Weatherby Mark V that I've killed a lot of elk with. I've been wanting the 30-378 for some time now. Set up will be 30-378 Accumark, Near Manufacturing rail and scope rings, Swaro x5i 3.5-18x50, and Javelin bipod. Waiting on brass and bullets to arrive. Will be testing out Berger 215 and 230 hybrids loaded with H1000, Retumbo, and IMR 8133 to see which one performs the best. Have Redding sizing die and Foster ultra micrometer seater. Will post some results as soon as everything comes in and can get some loads worked up. Cheers
If you don't take a look at RL26 and RL33 as powders you'll really be selling yourself short.

Congrats on the new rig.
 
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I have a HS Precision LRH chambered in 30-378 Wby, it loves 200 gr. Barnes LRX and 105 gr. H Retumbo at 3127 fps. I've shot several 1 inch groups at 300 yards, and have killed a Moose and a Brown Bear in Alaska. It really puts the hurt those big animals, with that big case I really like the tougher bullet that Barnes makes.
At warp speed the mono's really begin to shine. I have yet to recover a Peregrine fired from the .300 Rum and even on the biggest boars I generally get about a golf ball sized exit and absolute carnage throughout the vitals.

Shooting the .260gr VLR4 .375 Ruger I ran one from just below the anus and it still exited the left chest on a boar that ran around 550lbs and was running away at 365 paces.

For tough game you just cannot beat a good mono.
 
I learned about overbore reloads with my .257 Weatherby Mag. If given the PROPER powder, the 30-378 will walk all over the .300 UM. With the heavier bullets, it will really walk over the .300 UM. In a situation like this we are talking 200 FPS or so. Which is really meaningless but if anyone wants to use that against me, then you are beat again, as the .300 WM is as good as anything and more accurate on average than all the rest. Just food for thought. I'd never even look at Lazzeroni as they are too small a company. Maybe if I could handload to their numbers. My options are .300 WM and 30-378 Weatherby Mag. if more is needed.
None of these cartridges is inherently more accurate than the rest. It's all about the rifle/glass, the load, and the shooter.

With the right rig, right load, right idiot behind the trigger any of them can shoot well below MOA to a thousand yards or more.

The biggest difference between them is that the larger cases give you more velocity but that comes at a price in heavier recoil and bigger muzzle blast/flash.
 
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