The Midwest Industries AR-15 Barrel Nut Wrench (brand part no. BNW) is a professional-grade armorer’s tool built for installing and removing key AR-platform components on 5.56 and 7.62 rifles. Midwest Industries machines it from 17-4 stainless steel with a dedicated drive end that fits every MI free-float barrel nut, including the CRMHD, CRM, SLH, CRT, CRLW, ULW, G3M, G4M, and SP Series handguards. A three-notch castle nut driver handles standard buffer tube castle nuts, and an integrated 1/2-inch drive interface lets you torque everything to spec with a torque wrench. Among gunsmithing tools, this wrench favors builders who run Midwest Industries handguards and want a single tool that also handles castle nuts.

Key Specifications

• Machined from 17-4 stainless steel for repeated heavy use.
• Drive end fits all Midwest Industries free-float barrel nuts.
• Compatible handguard lines include CRMHD, CRM, SLH, CRT, CRLW, ULW, G3M, G4M, and SP Series.
• Built-in three-notch castle nut driver handles standard buffer tube castle nuts.
• Features a 1/2-inch drive interface for use with a torque wrench.
• Designed for both 5.56 and 7.62 AR-platform rifles.

Frequently Asked Questions

Will this work with any AR barrel nut? It’s designed specifically for Midwest Industries free-float barrel nuts and standard three-notch castle nuts, not every aftermarket nut pattern.

Can I use it with a torque wrench? Yes, the 1/2-inch drive interface is built for torquing components to spec.

Buy the Midwest Industries AR-15 Barrel Nut Wrench

A dedicated drive for MI handguards plus a built-in castle nut driver makes this wrench a one-tool solution for AR builds and service work. Order it from our Lubbock, Texas gun shop for fast, direct shipping.