Comparing The Big Bores

4 x 4 Square Tube Test Results
Cartridge Distance Moved
in inches
Bullet Weight Velocity
in Ft. per sec.
Sectional Density
416 Rigby 19.5 400 grains 2400 .330
458 Winchester/
450 Nitro Express
22.75 500 grains 2150 .341
450 Ackley 30.5 500 grains 2400 .341
470 Nitro Express 27.25 500 grains 2150 .317
470 Mbogo 31.25 500 grains 2500 .317
470 Mbogo (Woodleigh Solid) 32.875 500 grains 2500 .317
500 Nitro Express 33.5 600 grains 2150 .330
505 Gibbs 27.5 525 grains 2300 .288
500 Jeffery 29.75 525 grains 2400 .288
500 A-Square 49.5 600 grains 2400 .330

This table shows that it takes a good combination of bullet weight, velocity and sectional density for good penetration and a hard hitting cartridge. Notice that the 505 Gibbs and the 500 Jeffery although they seem to have good bullet weight that their penetration and impact numbers are down due to a lower sectional density. The 416 Rigby has a high velocity and a high sectional density but a lower bullet weight therefore the 450 Nitro/ 458 Winchester with a much lower velocity but a higher sectional density and higher bullet weight hits harder. Notice that the 470 Nitro with the same weight bullet and same velocity as the 450 Nitro/458 Winchester hit harder even though the sectional density was lower. Can this be contributed to the greater cross section area? The extra 350 feet per second velocity of the 470 Mbogo over the 470 Nitro Express shows a very worthwhile gain, especially when trajectory is taken into consideration. Even the different shape of the Woodleigh solid over the Barnes solid shows a worthwhile gain in impact. Remember that this solid with the same velocity penetrated 18 inches further in the plywood penetration tests.

The 450 Ackley with the Hornady solid, the extra velocity and exceptional sectional density really picked up on the impact test. To keep it in perspective you would have to compare the figures with the 470 Mbogo figures using the Woodleigh solids. The Ackley had the best penetration with the Hornady solid in the plywood test with the Mbogo just two inches less but the Mbogo move the square tube 2.375 inches further with a comparable solid. The 500 Nitro Express even though it penetrated ten inches less than the 470 Mbogo in the plywood penetration test hit with a very slight increase in the impact test. This can again be contributed to a good combination of bullet weight and sectional density. When you boost that velocity to 2400 feet per second as in the 500 A-Square things really start to happen. You just have to be able to control it! Touching off a 600-grain bullet at 2400 feet per second from a 10.5 lb. firearm makes you remember things you were supposed to do last week. The recoil is definitely accumulative with a cartridge like this and it will lead to a shooters headache.

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