I have one AR I installed a 22 conversion unit in.
Now and then I put the regular AR bolt in to blow the gunk out of the gas port.
Grandkids like the 22lr in an AR.
And I like teaching them responsible firearms use.
Still remember handing the youngest son a 10-22 with a butler creek high cap magazine.
Told him to only shoot one or two shots and he proceeded to do an ammo dump.
