AR15 want to shoot 5.56 & 5.45
I now have plenty of 5.45x39 ammo. What parts do I need?
If I order a Spike's AR15 mid length in 5.56, what other parts will I need to shoot 5.45?
I see Spike's sells a part for shooting 5.45. Is that all I need or do I need a different barrel as well?
On a related note I saw you can switch a single part and shoot .22lr out of it in a youtube video. Is this true?