22lr can have near twice the PSI of 410s.................
Is there another rifle that has that LITTLE metal around a 22lr chamber????
While certainly not rifles, consider the thickness of the .22LR chamber walls of the steel cylinder on a tiny NAA mini revolver and the .22LR chamber walls of the aluminum cylinder on a Smith & Wesson 43C revolver.
The .22LR cartridge would necessarily have a far smaller cartridge case interior surface area against which pressure can act, compared to a .410 shell. Looking at the PSI numbers alone does not take this difference into account.
The thickness of .22LR rifle barrels is dictated by considerations other than just chamber pressure containment.
