Do not get me wrong..I love record breaking cartridges and I'm fascinated by these supermonsters.
When my collection will be complete I may eventually drop a grand and a half for a 338-378 (I wanted one for long time)
However, reason of the heart (and bragging rights) aside, what is the real practical advantage (for hunting or practical target shooting) of these two huge cartridges compared to the "regular" 300 Magnums (including Weatherby's own 300 Wby Mag) and 338 Win Mag??
Let's, for example compare the 338 WM and the 338-378 (I own a Vanguard in 338 WM)
Cost of the rifle
A Mark V 338-378 Synthetic (the basic version) will require well in excess of $1000-1200 compared to the Vanguard synthetic...and you do not get wood or fancy finishing and stuff. They both come with accuracy guaranteed.
Cartridge performance
338-378 200 gr. Accubond from Weatherby
3380 fps muzzle, 5075 ft/lb muzzle, 2254 fps left at 500y, 2256 ft/lb left at 500y
338 Win Mag 200 gr. Accubond from Double Tap
3075 fps muzzle, 4200 ft/lb muzzle, 2250 fps left at 500y, 2246 ft/lb left at 500y
338-378 225 gr. Barnes TSX from Weatherby
3180 fps muzzle, 5052 ft/lb muzzle, 2238 fps left at 500y, 2501 ft/lb left at 500y
338 Win Mag 225 gr. Nosler Accubond from Double Tap
2850 fps muzzle, 4058 ft/lb muzzle, 2130 ft/lb left at 500y (there is a typo in the velocity column showing only the number 2))
338-378 250 gr. Partition from Weatherby
3060 fps muzzle, 5197 ft/lb muzzle, 2125 fps left at 500y, 2507 ft/lb left at 500y
338 Win Mag 250 gr. Partition from Double Tap
2750 muzzle, 4200 ft/lb muzzle, 2025 fps left at 500y, 2280 ft/lb left at 500y
So the 338-378 start with about 25% muzzle energy advantage. At the 500y the two rounds are, for every practical purpose, basically equivalent.
The 338-378 ammo cost $139 a box, Double Tap 338 Win Mag is $44 (other brands even cheaper)
Even if you reload the brass is much more expensive for the 338-378.
Weatherby ballistic data is for 26" barrel, Double tap is 24"...out of a 26" barrel the 338 Win Mag would noticeably reduce the gap
I did not compare the trajectories because the 338-378 data is published for 300y zero, DT is for 200 or 250 depending on the load...of course the 338-378 will shoot few inches flatter.
The 338-378 will have much increased muzzle blast (you need a brake).
The difference, in published data, between the 300 Wby and the 30-378 (both 26" pipe) is no more than 100-150 fps in velocity for the 30-378 and within a handful of inches at 500y (both zeroed at 300y)...a box of 30-378 will cost you $129, the 300 Wby start from $39 (and you can chose from other manufacturers too)
Again, do not get me wrong, maybe one day I will buy one of these supermagnums, just for the fun of it but I ask to the experienced hunter/practical target shooter..what is the real usefulness of these hyper rounds compared to the standard magnums??
When my collection will be complete I may eventually drop a grand and a half for a 338-378 (I wanted one for long time)
However, reason of the heart (and bragging rights) aside, what is the real practical advantage (for hunting or practical target shooting) of these two huge cartridges compared to the "regular" 300 Magnums (including Weatherby's own 300 Wby Mag) and 338 Win Mag??
Let's, for example compare the 338 WM and the 338-378 (I own a Vanguard in 338 WM)
Cost of the rifle
A Mark V 338-378 Synthetic (the basic version) will require well in excess of $1000-1200 compared to the Vanguard synthetic...and you do not get wood or fancy finishing and stuff. They both come with accuracy guaranteed.
Cartridge performance
338-378 200 gr. Accubond from Weatherby
3380 fps muzzle, 5075 ft/lb muzzle, 2254 fps left at 500y, 2256 ft/lb left at 500y
338 Win Mag 200 gr. Accubond from Double Tap
3075 fps muzzle, 4200 ft/lb muzzle, 2250 fps left at 500y, 2246 ft/lb left at 500y
338-378 225 gr. Barnes TSX from Weatherby
3180 fps muzzle, 5052 ft/lb muzzle, 2238 fps left at 500y, 2501 ft/lb left at 500y
338 Win Mag 225 gr. Nosler Accubond from Double Tap
2850 fps muzzle, 4058 ft/lb muzzle, 2130 ft/lb left at 500y (there is a typo in the velocity column showing only the number 2))
338-378 250 gr. Partition from Weatherby
3060 fps muzzle, 5197 ft/lb muzzle, 2125 fps left at 500y, 2507 ft/lb left at 500y
338 Win Mag 250 gr. Partition from Double Tap
2750 muzzle, 4200 ft/lb muzzle, 2025 fps left at 500y, 2280 ft/lb left at 500y
So the 338-378 start with about 25% muzzle energy advantage. At the 500y the two rounds are, for every practical purpose, basically equivalent.
The 338-378 ammo cost $139 a box, Double Tap 338 Win Mag is $44 (other brands even cheaper)
Even if you reload the brass is much more expensive for the 338-378.
Weatherby ballistic data is for 26" barrel, Double tap is 24"...out of a 26" barrel the 338 Win Mag would noticeably reduce the gap
I did not compare the trajectories because the 338-378 data is published for 300y zero, DT is for 200 or 250 depending on the load...of course the 338-378 will shoot few inches flatter.
The 338-378 will have much increased muzzle blast (you need a brake).
The difference, in published data, between the 300 Wby and the 30-378 (both 26" pipe) is no more than 100-150 fps in velocity for the 30-378 and within a handful of inches at 500y (both zeroed at 300y)...a box of 30-378 will cost you $129, the 300 Wby start from $39 (and you can chose from other manufacturers too)
Again, do not get me wrong, maybe one day I will buy one of these supermagnums, just for the fun of it but I ask to the experienced hunter/practical target shooter..what is the real usefulness of these hyper rounds compared to the standard magnums??
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