How did I miss this topic earlier?
First, a brief 10mm primer:
http://www.geocities.com/mr_motorhead/10mminfo.html
10mm Auto is easily my favorite handgun cartridge. I've owned several, and am waiting on my new Delta Elite to get to me once the FFL-to-FFL transfer gets done with. Its virtues are:
1. Power. 10mm Auto is the most powerful cartridge you can get in a factory autoloader of practical size. Factory hunting loads from Cor-Bon are pushing 700 foot-pounds of energy at the muzzle from a 4.6" barrel. Esoteric wildcats like .45 Super and .400 Cor-Bon can sometimes match, but not surpass, 10mm Auto ballistics. Neither one has loads that offer the deeper penetration potential of the 200-220gr 10mm loads. Only wildcats like .40 Super or .460 Rowland give you more muzzle energy, by which point you've pushed your handgun literally to the breaking point.
2. Versatility. As an autoloader cartridge, 10mm is unsurpassed in its versatility. Bullets from 135-220gr, speeds from 900-1,800 ft/sec, with 10mm you can handle anything from hunting to self-defense to plinking to competition. If it doesn't need a .44 Magnum to get done, 10mm can do it.
3. Accuracy. 10mm Auto is capable of an extremely high degree of accuracy. With a
drop-in Bar-Sto barrel my old Delta Elite shot into 0.8" at 25 yards. Even factory stock 10mm guns in general seem to have an unusual tendency to be very accurate. Full power 10mm loads are, of course, very flat-shooting as well due to their high velocity.
4. Safety. This isn't brought up often, but there is a reason you don't hear about 10mm guns having kB!'s like .40 S&W, .38 Super or even .357 Sig. The 10mm Auto case was designed from the ground up to stand up to high pressures safely... in fact, the case was designed to stand up to 53,000 CUP, with most published "max" loads being only 38,000 or less. Even with handloads, if you are using good 10mm powders (e.g. AA#7 & #9) you will sometimes run out of case capacity before your load is hot enough to be of concern.
USUAL DISCLAIMER: Don't be stupid when you handload. You CAN blow up a 10mm if you are dumb enough.
There are some downsides to 10mm, though they aren't deal-breakers.
1. Ammo availability. Every major company makes 10mm ammo for every conceiveable use, and if you shop around you can actually pay less for 10mm practice fodder than .45 ACP. But your corner store might not have it on the shelf, or might charge something stupid like $15 for Speer Blazers.
The best bargain for getting lots of 10mm ammo is Georgia Arms, though you can also find good sales on Blazer from Natchez. It is also a great cartridge to handload for.
http://www.georgia-arms.com/pistol.htm
http://www.natchezss.com/
2. Platform size. 10mm Auto requires a platform big enough to handle .45 ACP (since the cartridge overall length is about the same). If you want an itty-bitty gun, then 10mm takes a back seat to 9mm, .40 S&W or .357 Sig.
