cockpitbob
NES Member
Of course, check it before firing it, but there's more than one way to see if it's safe to fire. You probably don't want to hear what I do.
I use good quality factory ammo because the brass is about the correct size. All I do to check headspace is take a new factory cartridge (if I'm at home I pull the bullet) and put a piece of Scotch Tape on its butt and see if the bolt closes easily. I keep adding a layer of tape until the bolt shows some reluctance to close, then I peel and measure the thickness of the tape. Now I know the excess headspace with a factory cartridge. If I have more than about 0.006" or 0.007" headspace on a 30-06 I would get a gauge and check it properly. SAAMI specs say max length brass is 0.0061" shorter than a max length chamber, so it's unlikely I'll get in trouble using my tape shim method, especially since the cartridge makers try to stay right in the middle of the tolerances so I'll probably never get a max length cartridge.
BTW, you can get the full SAAMI ammo specifications here
I use good quality factory ammo because the brass is about the correct size. All I do to check headspace is take a new factory cartridge (if I'm at home I pull the bullet) and put a piece of Scotch Tape on its butt and see if the bolt closes easily. I keep adding a layer of tape until the bolt shows some reluctance to close, then I peel and measure the thickness of the tape. Now I know the excess headspace with a factory cartridge. If I have more than about 0.006" or 0.007" headspace on a 30-06 I would get a gauge and check it properly. SAAMI specs say max length brass is 0.0061" shorter than a max length chamber, so it's unlikely I'll get in trouble using my tape shim method, especially since the cartridge makers try to stay right in the middle of the tolerances so I'll probably never get a max length cartridge.
BTW, you can get the full SAAMI ammo specifications here
Last edited: