The belief that 10mm Auto is equal to .41 Magnum comes from one of Remington's loading manuals which featured an extremely underpowered .41 Magnum load they were offering at the time, which resulted in the lay person reaching the conclusion that 10mm Auto can be loaded to the same levels as .41 Magnum.

Sadly, 10mm Auto is simply one of the most overhyped pistol cartridges in history. Often touted by enthusiasts as an incredible, Grizzly-slaying cartridge which offers magnum level ballistics in a semiautomatic pistol and effectively renders magnum revolvers obsolete. Meanwhile, the vast majority of factory loaded 10mm Auto ammo is loaded no hotter than .40 S&W, and at absolute best it performs only a bit better than .357 Magnum. Not to say that it's a bad cartridge or anything, merely that it's a massively overrated cartridge, and it most certainly isn't the only pistol cartridge which has received more hype than it could possibly deliver.

That being said, this poll/thread isn't about muzzle energy or power factor of cartridges, merely the bullet's caliber or bore diameter.

__________________
Shooting Comfort is bilateral.