30-378 Weatherby Mag

I was wanting to buy off the shelf. Another option I'm considering is the 338 LM. I know ammo for both is expensive
Probably wise to buy off the shelf as in new. I'd be hesitant to buy a used .30-378 (or 7 rum, or 6.5-300 wby, or 26 Nosler….) as the barrel erosion is a real concern and unless verified by borescoping you could be buying a shot out barrel
 
Just picked one up a month ago, love it kinda finicky to load for as each gun has its preferenc. It's all in what you want to do and spend to get there. After loading test rounds with the big cases I look at my 300 wby cases and wonder if I have enough gun. These loads are a tad hot
 

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For off the shelf you won't beat that 30-378. 300 RUM or 30 Nosler would be your closest contenders but they are still a few hundred fps short. IMO the only good thing 300 PRC has to offer is it's efficiency and to me that's not a selling feature.
ballistically 338LM isn't going to outrun that 30-378 until past a mile. it will retain more energy for sure.
Sounds like you already have a 300wm, any reason you want to go away from it?
 
For off the shelf you won't beat that 30-378. 300 RUM or 30 Nosler would be your closest contenders but they are still a few hundred fps short. IMO the only good thing 300 PRC has to offer is it's efficiency and to me that's not a selling feature.
ballistically 338LM isn't going to outrun that 30-378 until past a mile. it will retain more energy for sure.
Sounds like you already have a 300wm, any reason you want to go away from it?
The win mag isn't going anywhere lol. I love the caliber and it's capabilities. I'm just looking to "broaden my horizon" and try something new
 
The win mag isn't going anywhere lol. I love the caliber and it's capabilities. I'm just looking to "broaden my horizon" and try something new
If you are looking to "broaden your horizons" how about a 338-378 more calibers is more fun and you already have a very capable 30. If you were looking for something off the shelf it's a wicked cartridge. If you go something custom in the way of a 338 lap-improved you have better brass that will last longer and take more but cost of everything will be more and require custom dies but if this is about trying something new why not try out having something built.
 
If you are looking to "broaden your horizons" how about a 338-378 more calibers is more fun and you already have a very capable 30. If you were looking for something off the shelf it's a wicked cartridge. If you go something custom in the way of a 338 lap-improved you have better brass that will last longer and take more but cost of everything will be more and require custom dies but if this is about trying something new why not try out having something built.
I was thinking about doing a custom build as well. I'd probably end up going with the 338 LM. It's a tried and true cartridge, plenty of components available and tons of reloading data. I don't have any experience with wildcats but I'm sure there is a lot of info I could read up on.
 
check out the 338-378 weatherby then, gets you a couple hundred over the 338LM but for any calculations I've done the sweet spot ballistically seems to be around 3000fps or north.
If you are building a couple other options would be 33XC, 338 EnABELR both these options should be pretty easy to acquire reamer, brass and dies for and there is enough data out there to get you started.

Allen Precision has their 2 chambering's in 338 that kick *** pretty hard also but you have to use him to build the rifle (not a bad thing just local is nice sometimes) then you have to fire form brass also
 
Hello all
I'm considering buying a .30-378 Weatherby mag. I'm looking for something that would be a long range hunting/target rifle. I was wondering a few things:

1). Does anyone have any experience with this caliber?

2). I've heard they're barrel burners (less than 1000 rounds) and have a lot of throat erosion.

3.) What would be the cost of hand loading?

4.) What would be a better option?

Thanks!!
I own a 30/378 mark V. It shoots well after I did some stock work. I shoot 230 grain Berger's and if you can settle in and relax it will cut holes. I never pushed it up. I use H50 powder. A good person to talk to about that caliber is Bob Wolfe the son of the late Howard Wolf. They use to shoot the 7300 weatherby and 30/378 for 1000 yard matches.
 
Get Mark V Accumark, put a big muzzle break on it and get reloading dies. This thing is a hot rod. It Holden an LR record at 1000 yards for very long time. It kills everything it hits. PS. You don't have to load it too hot, except the hunting loads, and the barrels will last you a while.
 
Get Mark V Accumark, put a big muzzle break on it and get reloading dies. This thing is a hot rod. It Holden an LR record at 1000 yards for very long time. It kills everything it hits. PS. You don't have to load it too hot, except the hunting loads, and the barrels will last you a while.
I've got the Accumark in .300 win mag and it's a blast to shoot. Literally lol
 
I used a 36" barreled 30x378 on a custom action for long range PA hunting for about 30 years.
My velocity using a 200 gr SMK was 3500 fps.
The 200 gr outperformed the heavier bullets as for trajectory out to about 1500 yds.
Very very few shots are ever taken on animals especially in PA past 1500 yds due to conditions during the hunting season.
Anything less than a 30" barrel even with the modern powder, will not produce the velocity necessary to receive full benefit from the 378 case.
My advice for a 30 cal would be a lesser cartridge for that reason for hunting.
Also most hunters arent equipped for shooting that far anyway.
All Pa l/r hunters use a bench or something similar, and they all use the spotter system when shooting at animals.
As for the 338, go big or dont bother would be my advice.
The 338x378 is the most popular 338 in the area of PA i hunt.
My son has one with a 30" barrel and he like all the others struggle to reach 3000 fps with 300 gr bullets.
The 416 Rigby case is slightly better, and the improved version of that case better yet.
Most are using 250 gr for hunting for that reason and find that out to about 1 mile they perform better than the 300 does.
Make no mistake by what im saying, as the 338 will make you a better shooter at the longer distances with the heavier bullets.
But you should really watch them all fly across a wide valley towards a target before deciding.
And once you do then there wont be any deciding, because the cartridge will do it for you.
You wont be needing to be reading any statistical information.
 
I used a 36" barreled 30x378 on a custom action for long range PA hunting for about 30 years.
My velocity using a 200 gr SMK was 3500 fps.
The 200 gr outperformed the heavier bullets as for trajectory out to about 1500 yds.
Very very few shots are ever taken on animals especially in PA past 1500 yds due to conditions during the hunting season.
Anything less than a 30" barrel even with the modern powder, will not produce the velocity necessary to receive full benefit from the 378 case.
My advice for a 30 cal would be a lesser cartridge for that reason for hunting.
Also most hunters arent equipped for shooting that far anyway.
All Pa l/r hunters use a bench or something similar, and they all use the spotter system when shooting at animals.
As for the 338, go big or dont bother would be my advice.
The 338x378 is the most popular 338 in the area of PA i hunt.
My son has one with a 30" barrel and he like all the others struggle to reach 3000 fps with 300 gr bullets.
The 416 Rigby case is slightly better, and the improved version of that case better yet.
Most are using 250 gr for hunting for that reason and find that out to about 1 mile they perform better than the 300 does.
Make no mistake by what im saying, as the 338 will make you a better shooter at the longer distances with the heavier bullets.
But you should really watch them all fly across a wide valley towards a target before deciding.
And once you do then there wont be any deciding, because the cartridge will do it for you.
You wont be needing to be reading any statistical information.
I agree
You should have a longer barrel to get your performance
 
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