If you have a .45, 40 or something that a crayon won't work with, get some canning wax from the grocery store that is 1/2" thick, let it soften, and push the case mouth into the wax, twist and you have a bullet. Great indoor or basement practice.thanks everybody for your input. I think that I may try the primer only and crayon or plastic or earplugs and see what happens with a few of them. I do not believe that I will load up live ammo with them. I appreciate all the input.
If you have an AR in .223 you can use a small pistol or small rifle primer to power a .22 pellet. Shotgun primer works best but one has to modify the case to accept one which isn't hard. A 209 primer will power a .22 pellet through a 2X4.
You used to be able to buy them through Sportsmans Guide, but since I"m flush with a lot of 209 primers and a lathe, I modified the cases myself. One can do it with a hand drill though.