Interestingly enough, .40 brass is inherently stronger than the original 10mm brass because the .40 S&W always used a small pistol primer and classic 10mm has always used the large pistol primer, leaving more brass in the case head with the shorter round.

In theory, if you can safely load the bullet long (and yet maintain bullet pull), you can also safely load the .40 closer to 10mm if you can mimic the space.

Approaching cautiously (and already using a 10mm pistol), this isn’t anywhere near as “DANGEROUS!” as far too many will try to make you believe.