AR-15 .22 Conversion Kit vs. Dedicated Upper: What Testing Shows

Cheap .22 LR practice through your AR-15 comes down to a choice: a drop-in conversion kit or a separate rimfire upper, and Brownells lays out what you give up and gain with each.

Snapshot

A new Brownells video compares the CMMG Bravo .22 LR conversion kit against a dedicated rimfire upper for AR-15s. Brownells' Caleb covers cost, accuracy, and fouling tradeoffs, while AmmoLand's own 600-round test of the Bravo kit found zero malfunctions and groups around 1.6 inches at 50 yards.

Key points

• Conversion kit, low cost: The CMMG Bravo swaps in a blowback bolt carrier and chamber adapter that lets an existing centerfire upper fire .22 LR, with Caleb citing ammo costs around seven to eight cents a round.
• Testing backs it up: AmmoLand contributor Jim Grant fired 200 rounds each through a PSA pistol, a LaRue carbine, and a BCM rifle, 600 rounds total, with no malfunctions and 1.6-inch groups at 50 yards.
• Dedicated upper, better accuracy potential: Brownells favors a purpose-built rimfire barrel and bolt assembly, arguing it's designed around .22 LR from the start rather than adapting a centerfire chamber.
• Fouling stays separate: A dedicated upper keeps rimfire lead and residue out of the centerfire barrel and gas system; Brownells recommends copper-plated bullets with the conversion kit to limit buildup.
• Cost versus convenience: The dedicated upper costs more but can stay assembled with its own zeroed optic, which Caleb considers worth the extra money for regular rimfire shooters.

Quick take

Neither option is wrong here. If you want occasional, cheap trigger time on a rifle you already own, the Bravo kit has AmmoLand's own testing behind it. If you're putting hundreds of rimfire rounds through your AR-15 every weekend, Brownells' case for a dedicated upper, better accuracy and no fouling headaches, makes sense.

Read the full story: ammoland.com