Not long ago, I shared a picture of a few 10mm Auto cartridges on social media where I said: “When 9mm isn’t enough, there is always 10mm!” One of the responses I received was, “Not as good as .45 ACP”. Which got me asking myself, “well which is better?”
Now let me preface this by saying I’m not looking to get into another caliber debate like the age old “9mm vs .45 ACP” debate. At the end of the day, I think it simply comes to preference for application. But I still find it fun to compare cartridges against each other.
Let’s begin by looking at some advertised muzzle velocities and energies for some factory loads.
Advertised ballistics for Federal Premium HST:
| Cartridge | Bullet Weight | Muzzle Velocity | Muzzle Energy |
| .45 ACP | 230 gr | 890 fps | 404 ft-lbs |
| 10mm Auto | 200 gr | 1130 fps | 567 ft-lbs |
Advertised ballistics for Hornady Custom XTP:
| Cartridge | Bullet Weight | Muzzle Velocity | Muzzle Energy |
| .45 ACP +P | 230 gr | 950 fps | 461 ft-lbs |
| 10mm Auto | 180 gr | 1275 fps | 650 ft-lbs |
Advertised ballistics for Underwood Ammo Xtreme Penetrator:
| Cartridge | Bullet Weight | Muzzle Velocity | Muzzle Energy |
| .45 ACP +P | 200 gr | 1000 fps | 444 ft-lbs |
| 10mm Auto | 140 gr | 1500 fps | 700 ft-lbs |
Based on the advertised ballistics, it seems to me that the 10mm, although being a smaller projectile in terms of weight and diameter, leaves the handgun with more velocity and more energy. This would make me assume that the 10mm is ballistically superior to the .45 ACP.
Being ballistically superior alone doesn’t make a cartridge superior. Capacity arguments usually follow in these caliber debates. As far as these cartridges go, capacity seems to be similar. For instance the 1911 type pistols can be found chambered for both cartridges and tend to be single stack configurations with eight (8) round capacity magazines. Sig Sauer offers the P220 pistols in both .45 ACP and 10mm Auto configurations which also happen to use single stack eight round magazines. Springfield Armory offers some of their XD-M pistol variants. These striker fired polymer framed guns accept double stack magazines with a 13 .45 ACP round capacity and a 15 10mm Auto round capacity. Glock also offers their striker fired polymer framed guns which accept double stack magazines in these calibers. Like the Springfields, the Glock 10mm Auto pistols then to hold about 2 more rounds than their .45 ACP counterparts.
Even though it appears that 10mm Auto is ballistically superior and slightly better when it comes to capacity it comes with a caveat. The caveat being recoil. When it comes to 10mm Auto recoil, one can expect about 75% more recoil when firing a typical 10mm Auto round compared to .45 ACP out of a similar gun. In my opinion, thats enough to require the more recovery time between shots for 10mm Auto from the same shooter. Not to mention an increased risk of flinching and recoil anticipation from an average shooter. Some folks will argue that this is something that can be resolved with training. However, I’ve found that somebody who has trained to be proficient in heavy recoiling rounds tend to still shoot lighter recoiling rounds faster and more accurately.
Thing is, I can’t really declare a real overall winner here. I believe it comes down to personal preference and application limited by individual skill.
For self defense against criminal threats, one can pick their poison as long as proficiency with the round has been achieved. I personally prefer cartridges I can shoot faster and more accurately as long as they are ballistically sufficient. Between 10mm Auto and .45 ACP, I prefer .45 ACP for this application.
For defense against wildlife, I tend to prefer rounds with as much ballistic oomph as I can get as long as I’m proficient with it. This is because the wildlife threats in the areas that I tend to hunt include hogs which tend to have thick tough hides. If I was in bear country, I would also lean towards this preference. For this application, I prefer 10mm Auto over .45 ACP.