You cannot judge relatively obscure (compared to a lot of others!) cartridges like the 41Mag and 10mm by browsing Winchester's site.
These are high-performance rounds and are best served by small ammo houses that specialize in brewing up "the good stuff". The three best are DoubleTap Ammo, Buffalo Bore and Grizzly Ammo...the latter only does hunting hardcasts.
When you understand how far THOSE guys push these babies, then you'll understand what's possible with them. (You can get close to these guys with careful handloading but at the ragged edge, they have pressure test gear and access to funky powders and you don't. That's why this stuff is so pricey...)
DoubleTap started out as a 10mm specialty house, so let's look there first:
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10mm 180gr. Controlled Exp. JHP 50rds. $38.95
This loading provides a hunter with a controlled expansion bullet at serious speeds!
Caliber : 10mm
Bullet : 180gr. Controlled Expansion JHP
Ballistics : 180gr. @ 1350fps/ 728 ft/lbs- Glock 20
http://www.doubletapammo.com/php/catalog/product_info.php?cPath=21_25&products_id=122
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Trust me: Winchester has NOTHING like that!
Browse the rest of their 10mm here:
http://www.doubletapammo.com/php/catalog/index.php?cPath=21_25
Tim Sundles at Buffalo Bore is more of a revolver guy so let's look at his 41Maggies:
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Heavy .41 Magnum Ammo - 170 gr. J.H.P. (1,650 fps/M.E. 1,028 ft. lbs.) - Item "16C"
Check these velocities taken from real guns.
1. 6.5" Ruger
c. Item #16C - 1640 fps
2. 4" S&W Mountain Gun
c. Item #16C - 1551 fps
http://www.buffalobore.com/index.php?l=product_detail&p=95
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Upshot: both are powerhouses but the 41Mag is at around 1/4 more potent.
As an aside: the best Buffalo Bore 357 loads are matching the 10mm. So it's no surprise the 41 is winning out when you take it to the edge.
Which one is really better? Loaded to the max, both the 10mm and 41 are reasonable personal defense loads for black bear, and could hunt deer and boar up to a reasonable size...run into the rare 600lb piggie and yeah, you'll be wishing you had more. Like maybe an airstrike
.