The WMD Big Beast .308/7.62×51 semi-auto rifle (WMD part no. 1-NIBX308C) scales up WMD’s benchmark NiB-X-coated AR-10 platform to full .308 Winchester performance. Every internal and external metal surface is treated with WMD’s proprietary NiB-X nickel boron coating, engineered to reduce friction and fouling for a rifle WMD built to be exceptionally reliable and low-maintenance under hard use, whether that is a hunting trip or a long day at the range.

Key Specifications

• Chambered in .308 Winchester / 7.62×51 NATO, giving substantially more downrange energy than a 5.56 AR-15.
• The 18-inch barrel balances maneuverability with the extra velocity a .308-caliber barrel needs.
• Feeds from a 20-round magazine for a solid on-board ammunition supply.
• Finished with WMD’s proprietary NiB-X nickel boron coating, giving the Big Beast its distinctive silver appearance and low-friction, low-maintenance operation.
• Built on WMD’s semi-auto AR-10 platform, engineered for reliability under sustained hard use.
• Sold and configured as a complete rifle, part of WMD’s benchmark AR-10-pattern Beast lineup.
• Wrapped in a free-float M-LOK handguard with fully adjustable accessory rails.
• Rifled with a 1:10 twist rate paired with a Melonited bore for long-term accuracy.
• Runs a direct-impingement, carbine-length gas system.

Frequently Asked Questions

What is NiB-X coating? It is WMD’s proprietary nickel boron finish applied to internal and external metal parts to reduce friction and fouling, which is also what gives the Big Beast its silver look.

What caliber does the Big Beast fire? It is chambered in .308 Winchester / 7.62×51 NATO, WMD’s AR-10-pattern caliber offering.

Buy the WMD Big Beast .308/7.62×51 Rifle

WMD built its reputation on the original 5.56 NiB-X Beast, and the Big Beast brings that same low-maintenance coating to a .308-caliber AR-10. Backed by WMD Guns and part of our semi-auto rifles lineup, it suits hunters and range shooters who want a low-maintenance .308 platform. Order it from our Lubbock, Texas gun shop for fast, insured shipping to your FFL.