new 30-378 loads
- Thread starter 308Loader
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Roadkill2228
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the 30-378 is to most "magnum" cartridges what magnum cartridges are to standard ones. A horrible case of diminishing returns imo, burning between 25-40 percent more powder than the .300 weatherby for a 150 fps increase in velocity, at least out of standard length barrels with standard hunting weight bullets. This beast would be much more impressive with 30+ inch barrels shooting bullets 210 grains and up. I already observe in my .300 win mag a tendency toward non-linear gains when shooting heavy for caliber slugs...that is, it performs more efficiently with them. Its hard to make 150 grainers reach the same level of kinetic energy at the muzzle as can be readily attained with 200s. This will be all the more the case with this 30-378. Shooting light bullets out of cartridges with these case to bore ratios is like choosing to use a big truck with a huge v8 for everyday driving. It offers little or no advantage over a smaller vehicle with a smaller engine, where the big v8 serves any real purpose is pulling something heavy on hilly roads. To use it to go to the post office is kind of wasting its potential (and highly inneficient) So enough analogies and ranting, what Im saying is you'll likely have better results with the heaviest bullets you can load. One thing the reloading manuals should all spell out clearly is that cartridges of this size and case to bore ratio can be much more dangerous when underloaded than overloaded. Just as you wouldn't start out with an over-book-max load, do not under any circumstance try making "reduced" loads (under book min) - why anyone would want to do this with a .30-378 is beyond me anyways, but, it must be said, hangfires and detonations are a real possibility if you dont stay in the perscribed range. The slowest of powders are your friends. RL 25, H1000, H870, Retumbo, H50BMG, RL33. IMR7828 is probably way to fast a burn rate for optimal performance with this round (which is saying something).
aussie copper projec
New member
I have years and years and thousands apon thousands of rounds down with the 30-378. Great round imho, i run either the 155 or 175gr acp (my product yes so im biased) and they are just awesome on pigs, dogs horses camels, donkeys buffalo goats etc etc her in aus. i use re25 a lot or adi 2225...... if you need help i have pressure data and quickload here so i could point you in the right direction if i get all your case trim lengths capacities etc
If you want low cost ammunition, try getting some of the slower surplus WC870 or 872 series powders. Wideners usually has them, GIBrass.com has some currently listed. You can use H870 data for a starting point.
220 grain Nosler Partition bullet
3098 fps by 113.0 grains of H870 powder
3180 fps by 116.0 grains of H870.
While the Nosler Custom Competition 220gr HPBT isn't the same type of bullet as the Partition, I feel comfortable substituting the match bullet for the hunting bullet because it the lead core of the match bullet is easier to deform than the Partitions solid copper center.
If you by an 8 lb jug of WC870 powder and use 110gr of powder per charge, that's 500 loads for your dad's rifle.
That means you need to buy 5x 100 count boxes of the Nosler CC bullets, around 38 bucks a piece, which is 190 bucks.
190 + 78 bucks (powder plus hazmat fee) = 268 dollars for 500 bullets, or just over 50 cents a trigger pull, not including brass and primer.
Hope this is helpful.
aussie ill buy a box of your bullets if you send me some brass to launch them with. finally found some brass at the store, they want $70 bucks for 20! That's 20 unprimed cases. what the heck is the deal with this brass, is it that rare of a cal that they can fix the price? I know they are big brass cases but it cant be that hard to make the suckers.
Factory WBY rifles have a long throat... that allows the bullets to jump out a little before building pressure. It is normal and completely acceptable practice. Basically, with out getting to technical, it makes more little more space prior to full pressure.... ( giving more room for burning powder to expand in )
It is especially important with that specific cartridge.
Some other brand rifles usually have shorter throats.... and can show nasty pressure signs because of the lack of that jump. It can even happen with factory Weatherby ammo in those short throated rifles.
What is the throat length (free bore) on your Weatherby rifles chambered for Weatherby magnum calibers?
Cartridge Throat length (free bore)
.224 Weatherby Magnum .162
.240 Weatherby Magnum .169
.257 Weatherby Magnum .378
.270 Weatherby Magnum .378
7MM Weatherby Magnum .378
.300 Weatherby Magnum .361
.340 Weatherby Magnum .373
.375 Weatherby Magnum .373
.378 Weatherby Magnum .756
.416 Weatherby Magnum .239
.460 Weatherby Magnum .756
.30-378 Weatherby Magnum .361
.338-378 Weatherby Magnum .361
It is especially important with that specific cartridge.
Some other brand rifles usually have shorter throats.... and can show nasty pressure signs because of the lack of that jump. It can even happen with factory Weatherby ammo in those short throated rifles.
What is the throat length (free bore) on your Weatherby rifles chambered for Weatherby magnum calibers?
Cartridge Throat length (free bore)
.224 Weatherby Magnum .162
.240 Weatherby Magnum .169
.257 Weatherby Magnum .378
.270 Weatherby Magnum .378
7MM Weatherby Magnum .378
.300 Weatherby Magnum .361
.340 Weatherby Magnum .373
.375 Weatherby Magnum .373
.378 Weatherby Magnum .756
.416 Weatherby Magnum .239
.460 Weatherby Magnum .756
.30-378 Weatherby Magnum .361
.338-378 Weatherby Magnum .361
When doing a load workup I like to find the accurate charge weight before I mess with seating depth.
Long freebore means that you'll probably have better luck with tangent ogive profile bullets than secant ogive profile bullets.
But, since even a 308 Win can get to 1,000 for target shooting, you'll have no problem doing so with a 30-378 Weatherby
Just don't get hung up on getting absolute max velocity because you really don't need it.
Jimro
Long freebore means that you'll probably have better luck with tangent ogive profile bullets than secant ogive profile bullets.
But, since even a 308 Win can get to 1,000 for target shooting, you'll have no problem doing so with a 30-378 Weatherby
Just don't get hung up on getting absolute max velocity because you really don't need it.Jimro
Ok, so I will have the rifle in hand soon. Found some H50bmg and WLRM primers. Projectile selection time. I have seen factory ammo as light as 150gr up to 220gr, the goal is accuracy first, then terminal ballistics. This round is hauling a** compared to 308 win with heavy bullets. What should I be looking for?