Description
CMMG .22 LR conversion kit or dedicated .22 LR upper? Caleb from Brownells compares two ways to shoot rimfire ammunition through an AR-15 and explains the cost, convenience, and accuracy considerations behind each option.
The conversion unit offers a simple way to use a compatible .223 Remington or 5.56 NATO upper with .22 LR ammunition. A dedicated upper adds a purpose-built rimfire barrel and matching bolt configuration. Caleb explains why he prefers the dedicated setup, while showing where the conversion kit makes sense for affordable practice and plinking.
This walkthrough also covers dedicated magazines, blowback operation, ammunition considerations, and the components used in the dedicated upper shown.
Which setup do you prefer? Leave your questions and experiences in the comments or contact the Brownells tech line.
Chapters
0:00 Introduction
0:15 Why shoot .22 LR through an AR-15?
0:51 Two approaches using CMMG components
1:09 Conversion bolt overview
1:50 Demonstrating the conversion unit
3:05 Dedicated .22 LR magazines
3:22 Ammunition and fouling considerations
4:05 Why Caleb prefers a dedicated barrel
4:34 Dedicated rimfire bolt and barrel overview
5:22 Dedicated upper components and tooling
6:30 Dedicated upper assembly overview
7:29 Muzzle device and handguard
9:11 Charging handle and final assembly
9:58 Which components are rimfire-specific?
10:18 Dedicated barrel advantages
10:57 Why keep a separate .22 LR upper?
11:19 Closing thoughts