Spending time with the .30-378 Weatherby.

**TStone** · 12-08-2022, 17:22

I spent the past 10 days guiding two American hunters, one of them used a .300 win mag (a cartridge with which I have a lot of experience) the other hunter used a Weatherby Mark V Accumark in .30-378 WM. I knew about the existence of the .30-378 but had never seen and had given very little thought to it.

When I did think about it I dismissed it as being grossly overbore (which it is), noisy (which it is), difficult to shoot well and probably inaccurate. The owner of the rifle shot 4 animals with it, he brought a smaller caliber as well, all were clean one shot kills. He missed one animal, a baboon, but made good on that with a quick, accurate follow up shot. A kudu bull and a waterbuck bull fell to one shot each at ±400m, a mountain reedbuck at 350m and the baboon at 130m (which is close for baboon). A petite 20 year old girl used the rifle to down a blesbuck at 400m, again with a single shot. The load he used launch a 180gr Barnes TTSX at ±3300fps.

Sighted dead on at 250m the rifle shoots 2 inches high at 100m, 2 inches high at 200m and 3 inches low at 300m. So you could hold dead on for shoulder shot at springbok from 0- 300 meters. It has a muzzle brake which bring recoil down to 7x57 levels but makes wearing ear plugs while hunting mandatory. It is easy to shoot accurately in a rifle which is light enough to carry all day. It is very accurate and the Barnes bullets performed well on all animals. At the end of the hunt, I got to shoot it and I am very impressed with its field accuracy and how it handles and shoots.

It does have some drawbacks. According to Google, barrel life is between 500 and 1000 rounds. It will destroy cup and core bullets and most bonded bullets. I would not use anything other than expanding mono metal bullets in it for hunting. It is certainly not a range rifle, not in the RSA anyway.

What I did not know is that it held the 1000 yard bench rest accuracy record for more than 30 years as a wildcat cartridge and that it was developed by Roy Weatherby in 1959 on request of the US military as a possible military cartridge.

I would not want one as an only rifle, mostly due to its limited barrel life and running cost, but it would make a great rifle for backing clients on large wounded antelope. It is also an excellent caliber for hunting large antelope in open terrain.

As impractical as it is for general hunting, I want one.

The .30-378 at the right (as if you couldn't tell) with a .308 win and a .30-'06 Springfield.

**Mahomedy13** · 12-08-2022, 18:11

Thanks for the writeup. Reading this also makes me want one

. One day when I get big and have money lying around...

Sent from my SM-S908E using Tapatalk

**oafpatroll** · 12-08-2022, 19:37

Great writeup, thanks. When you wildcat off a belted magnum parent case of your own you're Roy Weatherby!

**pblaauw** · 12-08-2022, 19:55

I wonder what the kick is without a brake, since the 300PRC I shoot kicks the living snot out of me, and this thing looks even meaner.

**Messor** · 12-08-2022, 19:59

I am willing to bet money that 308 kills just as dead as the overbore monster.

**Bushcourt** · 12-08-2022, 20:09

Originally Posted by Messor

I am willing to bet money that 308 kills just as dead as the overbore monster.

True... But it is a want vs. need question. Everybody wants to have another rifle!

**treeman** · 12-08-2022, 22:18

Surely that must be the Top Fueler of the cartridge world - that thing lead my mind straight to another form of extreme.

If permissible in this post just for interest sake - check the top fueler stats and you will see comparison reasoning.

One Top Fuel dragster 500 cubic inch Hemi engine makes more horsepower than the first 4 rows at the Daytona 500. They have over half again as much horsepower in one cylinder as a Dodge Viper has in all ten. No one has ever successfully run one long enough on a dyno to get a horsepower reading. Current estimates are right around 6,000 horsepower.

-Under full throttle, a dragster engine consumes 1-1/2 gallons of nitro methane per second; a fully loaded 747 consumes jet fuel at the same rate with 25% less energy being produced.

-A stock Dodge Hemi V8 engine cannot produce enough power to drive the dragster supercharger. The fuel pump alone requires more horsepower to turn than the average street car produces.

-With 3000 CFM of air being rammed in by the supercharger on overdrive, the fuel mixture is compressed into a near-solid form before ignition. Cylinders run on the verge of hydraulic lock at full throttle.

-The 1.7:1 air/fuel mixture for nitro methane produces a flame front temperature measures 7050 degrees F.

-Nitro methane burns yellow. The spectacular white flame seen above the stacks at night is raw burning hydrogen, disassociated from atmospheric water vapour by the searing exhaust gases.

-Dual magnetos supply 44 amps to each spark plug. This is the output of an arc welder in each cylinder.

-Spark plug electrodes are totally consumed during a pass. After the run, the engine is dieseling from compression plus the glow of exhaust valves at 1400 degrees F. The engine can only be shut down by running the car out of fuel. There is no way to cut off the fuel; the engine stops only when it blows or the tank runs dry.

-If spark momentarily fails early in the run, unburned nitro builds up in the affected cylinders and then explodes with sufficient force to blow cylinder heads off the block in pieces or split the block in half.

-In order to exceed 300 mph in 4.5 seconds dragsters must accelerate an average of over 4G's. In order to reach 200 mph well before half-track, the launch acceleration approaches 8G's. To put this in perspective; a top fuel dragster, parked next to a Super Hornet on the steam catapult on the deck of an aircraft carrier, would be in the water and sinking before the Super Hornet was halfway down the deck.

-Dragsters reach over 300 miles per hour before you have completed reading this sentence.

-Top Fuel Engines only turn approximately 540 revolutions from light to light!

-Including the burnout, the engine must only survive 900 revolutions under load. They only survive about 80% of the time.

-Redline at 9500 rpm.

-Assuming all the equipment is paid off, the crew worked for free, and for once NOTHING BLOWS UP, each run costs an estimated $1,000.00 per second.

-The engine is entirely rebuilt every run, or every 900 revolutions. New pistons and rings, new rods, new rod bearings. Sometimes a new crank. The crew does this in about two hours between rounds.

-The current Top Fuel dragster elapsed time record is 4.441 seconds for the quarter mile. The top speed record is 333.00 mph (533 km/h) as measured over the last 66' of the run.

-Putting all of this into perspective: You are driving the average $140,000 Lingenfelter "twin-turbo" powered Corvette Z06. Over a mile up the road, a Top Fuel dragster is staged and ready to launch down a quarter mile strip as you pass. You have the advantage of a flying start. You run the Vette hard up through the gears and blast across the starting line and past the dragster at an honest 200 mph. The 'tree' goes green for both of you at that moment. The dragster launches and starts after you. You keep your foot down hard, but you hear an incredibly brutal whine that sears your eardrums and within 3 seconds the dragster catches and passes you. He beats you to the finish line, a quarter mile away from where you just passed him. Think about it, from a standing start, the dragster had spotted you 200 mph and not only caught, but nearly blasted you off the road when he passed you within a mere 1320 foot long race course.