We are not against training with 5.56mm/.223 rounds as much as possible, but a question arises in these cash-strapped days: If it comes down to training or not training, or limiting the rounds fired, can we learn and substitute a 9mm carbine based on the AR platform for the larger rifle rounds?

Does it translate to shooting the 5.56mm/.223? The short answer is yes, and the Rock River Arms (RRA) LAR-9 is up to the task.

Easily Convert Your .223 AR Into Reliable Shooting 9mm

Sub-caliber upper assemblies allow fast and simple conversion of ARs chambered in .223 to 9mm Luger. True, dedicated, complete upper receivers are assembled from military specification components; includes a Wilson, 1-10 twist barrel, bolt and carrier, charging handle, shell deflector, heat-shield lined handguards, sling swivel, and A1-style flash hider.

Additional items not included but required for conversion to 9mm are a 9mm magazine AND magazine adapter, action spring, and recoil buffer.

A2 configuration has A2 adjustable sights regulated for 9mm.

A4 unit has flattop receiver that accepts most aftermarket accessories designed to fit a Picatinny rail.