Over the weekend I saw a box of .499 LWR, some new caliber for the AR platform, and obviously nomenclatured to circumvent California(?) ban on .50 caliber. Since that was the first, and only box of this ammo I've ever seen, or heard of, it would not be my choice for a doomsday weapon. The new rifles all seem to be getting heavier and more complicated. I think I would go with the old M1 Carbine should the day of reckoning arrive. No one wants to get shot with one, especially when medical care disappears. In the days before penicillin, .32 S&W Short was considered an adequate defensive round. Did you hear that the Massachusetts Supreme Court ruled that the state's rigid gun laws did not apply to handguns manufactured before 1900? Should I ever have the misfortune of going there, maybe I'll tote that old spur-trigger Protector in .32 Rimfire. Also considered an "Antique" under Canadian law. Though I'd not count on a Mass. Highway Patrol officer or Canda Customs flunky to understand that.

Patrick, there is way too much 5.56x45mm and 7.62x39mm in the world to introduce a new caliber ACR. That's what Russia did with the An-94 and look at how low the issue was. Most nations are just modernizing with synthetic materials, adding railings for accessories, and slapping on new vision equipment. Leave new calibers for PDWs! Rheinmetall AG has introduced laser flak in 50-100Kw and is still working out the bugs of the world's first plasma Rifle. If it doesn't work, HK will probably turn back to Caseless again as in the G-11. Dynamit Noble is still working on those for the cartridges as is Australian Metal Storm.

Patrick, you should know that US SFs are also using HK 417s when they can get them. Add that to the HK SOCOM .45s and UMP-45 SMG plus P-11 underwater pistol for the SEAL teams! US Army and Marine Corp interested in the new HK 121 LMG! Rheinmetall also introduced a new .50 heavy MG to replace all MG-3 and US M2s on German armor by 2017.

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Patrick, the.499LW is a loophole cartridge. A weird one is .458 SOCOM. Sporting .50s best is .50 Beo IMO...

That is what I thought. Haven't researched it yet. Didn't Barrett manufacture a rifle in .416 Rigby to get around the California ban? What little shooting I do is in confined areas. Working on a project to produce a few .32 rimfires. Even converted an old Clerke First potmetal SNS to shoot this obsolete round. Probably the first new revolver in .32 RF since 1910.

AFAIK, the .416 was ordered for the Barret M99 as alternative round with lower cartridge weight, same MV and ME of 8800 ft-lb vs 14,000 for the .50 version. The round was bottlenecked. What's amazing is that the conventional sniper .338LM round has almost the same MV as all the big Anti-Material rifles, but lower weight and ME of around 5000 ft-lbs! Barret is currently working with German metallurgists on special sub .50 hyper rounds!!! If projectile weapons are to survive beyond the new laser and plasma types, I think they will have to either become Caseless or be made of field conductive metals. Small railguns are known as "jumpsliders" of British origin. I think American version would be Coilsliders...