Thanks for reaching out! This ammo should function correctly in a converted 22 LR AR, absolutely. Its 1,200 fps muzzle velocity and 40gr bullet mean it generates adequate pressure to cycle a semi-auto. That said, I've always greatly preferred copper-plated (ie CPRN/CPHP) bullets for semi-autos seeing as how they keep the barrel cleaner – and in an AR's case, that copper plating tends to keep more lead residue out of the gas port/block as well. But too many people do just fine with LRN bullets to insist that copper-plated ones are necessary!