I just got a box of Lyman gas checks on pay it forward here. Looks like they (I’m guessing) are the old style slip on style and not made out of copper? They are golden color and have a little bit of spotting, her oxidation, rust, or something on the inside which tells me they are something other than copper.. I’m just wondering if there’s gonna be a change in accuracy using these versus the modern style crimp on copper checks?
Pretty looking vintage box. Doesn’t look like there’s a crimp ring on the inside of the checks where they would grab onto the bullet. I use a lee sizer when seating the hornady GCs. I assume I could seat these the same way?