The Battle Arms Development Workhorse complete lower receiver is a fully assembled AR-15 lower with a B5 Systems Bravo adjustable stock, ready for the upper of your choice (brand part no. WH-LR-R-B5). It is built on a forged 7075-T6 Workhorse receiver finished in Type 3 black anodize, and it ships assembled with Battle Arms’ enhanced controls rather than bare mil-spec parts. The listing carries the multi-caliber designation because the lower accepts any compatible AR-15 upper, so the caliber is decided by the upper you pair with it. For a builder who wants a finished lower without sourcing a fire control group, stock and grip separately, this one saves the parts hunt.

Key Specifications

• The platform is the AR-15, so it accepts standard AR-15 uppers and the wide range of calibers they are built in.
• The receiver is forged 7075-T6 aluminum, a strong and consistent alloy that suits a duty or range lower.
• The finish is Type 3 black anodized, a hardcoat that resists wear and corrosion.
• The stock is a B5 Systems Bravo adjustable stock, which lets the length of pull change to fit the shooter.
• The grip is an adjustable tactical grip, so the angle and feel can be tuned to your hand.
• The safety is an enhanced single-sided selector, giving a positive, easy-to-reach manual safety.
• The trigger is an enhanced nickel Teflon trigger, a coated part chosen for a smooth, consistent feel.
• The magazine release is an enhanced magazine release, which is easier to reach than a standard button.
• The bolt catch is an enhanced bolt catch, an upgrade over a plain mil-spec lever.
• The buffer is a standard carbine buffer, so the lower is complete and ready for an upper.

Frequently Asked Questions

Does this lower come with a stock? Yes. It is a complete lower with a B5 Systems Bravo adjustable stock and an adjustable tactical grip already installed.

What caliber is the Workhorse lower? It is listed as multi-caliber. The lower itself is caliber-neutral, and the caliber is set by the AR-15 upper receiver and barrel you attach to it.

What upgraded parts are installed? Battle Arms lists an enhanced single-sided safety, an enhanced nickel Teflon trigger, an enhanced magazine release, an enhanced bolt catch, enhanced takedown and pivot pins and a standard carbine buffer.

Buy the Battle Arms Development Workhorse Complete Lower Receiver

A complete lower is the quickest way to start an AR-15 build, and this one arrives with the stock, grip, trigger and controls already chosen and installed. Pair it with an upper in the caliber you want and you have a rifle. Order it from our Lubbock, Texas gun shop for fast, insured shipping to your FFL, and browse more AR-15 lowers while you are here.