I welcome all discussions
When checking a Japanese rifle I cover the receiver with a white towel. When the case does not seal the chamber the white towel has two distinct black dots and on occasion I get a very distinct black outline of the receiver. When checking the rifle I find the barrel is too large in diameter for the bullet. I had a 7mm Remington Mag that blackened the case neck meaning the powder was burning too slow to seal the neck but fast enough to seal the case body from the shoulder back, removing the carbon is not easy.

F. Guffey