Ten by one hundred millimeters or one centimeter by one decimeter, if you will – that’s the name of the new cartridge by Blackwater Ammunition. The 10×100 BWA is designed to be a long-range precision shooting cartridge that outperforms the .50 BMG in range and trajectory departments while remaining within the dimensions of .50 BMG cartridge.

The headstamp of 10×100 BWA cartridge.

This cartridge is based on a .50 BMG case which has been necked down to .408 caliber and improved (less case body taper, increased shoulder angle). According to Blackwater Ammunition, the 10×100 BWA has 20% more case capacity than the .50 BMG. The company notes that they’ve used the existing experience and achievements in cartridge designing and “the studies and developments of all the great modern cartridge designers are all here, with P.O. Ackley and Roy Weatherby just to name two“.

Blackwater Ammunition will offer these cartridges with their patented lightweight two-piece machined aluminum alloy cases loaded with solid (monolithic) bullets machined from a Carobronze alloy. The cartridge is advertised to be capable of pushing a 420-grain bullet to a muzzle velocity of 3,500 fps which results in a muzzle energy of 11,425 ft-lb. BWA notes that these bullets remain supersonic to up to 2.7 kilometers (1.68 miles) and outperform the .50 BMG “in terms of bullet drop more than 100% at any distance“.

BWA ammunition line as seen in the company’s catalog.

Because this cartridge is based on a .50 BMG case and has an overall length identical to .50 BMG, chambering rifles in 10×100 BWA should be only a matter of making a new barrel with all other parts (bolts, extractors, receivers, magazines, etc.) borrowed from .50 BMG guns. According to the company, they are working with industry partners to also offer chamber reamers and reloading dies for this caliber. A loading guide will be available, too. I think it should also be possible to make brass 10×100 BWA cases by fireforming necked down .50 BMG cases in 10×100 BWA chambers.

Those of you who are into long-range shooting, tell us in the comments section if you think this cartridge indeed offers something new or do you prefer another cartridge that provides similar ballistic performance.

Images by Blackwater Ammunition