So I got a few replies on the 10mmtalk forum, and figured I'd share one that was very helpful...it's a discussion on the very topic of 10mm vs. 45 ACP coincidentally. I found it useful, so I'll post it here and hope it helps anyone else who's curious.
--------------------------------------------------------------------------
OP: gunfan on 10mmtalk.com
--------------------------------------------------------------------------
10mm Advocacy Article
By Thomas Martens,
[email protected]
please contact the author at the above e-mail address with any
questions or comments
(For those of you who have sent me so many kind emails on this article, I'd like to thank you. I have moved it to my personal website due to the "Calibers" site being down for so long. I'd like to thank Todd for being the first one to post this article. Check back on occasion, as I will updating this article, and adding a TON of expansion pictures, and more data from Double Tap ammo. Tom)
If you have read this article, and just want to see the new expansion pictures, there are links at the end of the article.
Last updated 14 May 2007
This article deals with the 10mm automatic pistol cartridge, sometimes called the 10mm Norma. I’ll dispense with the history of the cartridge; there are enough articles around about that. My purpose is to expound upon the merits of this round, and to present some data to support my assertions. It is my belief that this cartridge, though never really popular, has not only suffered from the poor reviews many in the gun press have given the round, especially Chuck Taylor *, (it’s generally disrespected by most of them) but also from a total lack of understanding of its strengths. Tell me, when is the last time you saw an article on any gun for the 10mm. There are articles galore on the 1911, .40 Glocks, Sigs, etc. The 10mm is old news. Sexier cartridges have come on the scene like the .357 SIG and the .45 GAP. Heck, I’d swear there are more articles about cartridges like the .45 Long Colt than the 10mm. That’s a shame. I don’t pretend to know why they are so anti-10mm in the gun magazines. Every once in a while they’ll say something nice about it. Ayoob seems to at least appreciate the 10mm, and Rauch likes it too – though neither as much as the .45. They (the gun writers) are not the only culprits though. There can be no question that the FBI’s lightening of the round in terms of velocity, and the subsequent introduction of the .40 caliber cartridge are also, in part, responsible for the 10mm’s lack of wide spread popularity. Still, this is an excellent cartridge - the best all around cartridge for a handgun, in my opinion. Finally, however, interest in the cartridge does seem to be on the rise at long last, and many .40 caliber shooters have either gotten the bug for more power, or have made the progression to the 10mm because they re-load the .40, and they can use the same dies and many of the same powders for the 10mm.
The approach I will take in this article is primarily to show why the 10mm beats the .45 ACP. But I will be making a few references to other popular defense calibers as well.
About the Author
Before I begin in earnest, bear with me, I’d like to reveal some of my prejudices and a little background information about me to orient the reader.
I joined the Marines at 17 and was fortunate enough to pass number of strange tests, and a host of other things before I received a Category I Top Secret clearance and sent to Camp David to guard President Reagan. We carried a bunch of different weapons up there, and one of those we carried around a lot was a1911 .45. More than a few of us owned our own, and were even known to quietly replace our issue .45s with our personal guns (and ammo sometimes) while on duty. My last 18 months or so I lived on a farm in Pennsylvania and so had plenty of land to take my .45 and train, train, train with it. But I also was curious about the 9mm, and in 1985 bought a gun few of my fellow Marines had ever heard of, a Sig Sauer P226. Though I really liked the gun, particularly its large magazine capacity, I was less than enthralled with the 9mm cartridge - save that I could shoot it fast and accurately - something I’ve since learned that can be done with any handgun with a bit of dedication and practice. I left Camp David in 1986 before a single Beretta arrived. Suffice it say we hated the idea of a 9mm anything replacing our beloved .45s. I love the .45 ACP, and I own more than one gun for this cartridge. To me, I just feel safe with a gun chambered for that round, and nothing, save the 10mm, makes me feel better. However, after a lot of thought, reading and research, a few years back I sadly relegated my .45s to back up roles for home defense, in favor of the more potent, and more effective 10mm auto.
--------------------------------------------------------------------------------
Crowds
When it comes to ammo selection, I’m a convert from the lightest and fastest camp to the medium to heavy weight bullets. Thing is, even when it comes to heavy, I want the fastest "heavy" I can find. In my Colt Delta Elite, and my Glock 20, I load up with Pro Load’s 180 gr Gold Dot HP. In my Delta Elite this load, rated at 1200 fps, comes out nearly dead on at 1207fps, and at 1176 fps in my Glock 20. At well over 500 foot pounds of energy each, these are hot loads. I also like the Winchester 200gr Black Talons in my Glock 20 loaded up with 8.2gr. of Long Shot and the 6” barrel. A couple of other bullets that seem to work very well at 10mm velocities is the PMC 180gr Starfire that I load up with 9.6gr. of Long Shot, or the Remington 180gr Golden Saber. If you like carrying reloads for defense or hunting, these loads have worked well in my tests, even out of the Glock 29. I also carry the 180gr Pro Loads in my Glock 29. All the testing I’ve done with this round show it is also a great performer out of shorter barrels; something about that Gold Dot bullet. However, I have been known to carry the Hornady 155gr XTP in this gun. I was never a believer in this bullet as the meplat just looks like it will not open up – but looks can be deceiving. I trust Steve Hornday’s designers. All my (unscientific) tests have showed the XTP to be a top performing bullet design. I load my Colt .45 with Cor Bon’s 230 gr JHP+p. My Para-Ordnance P12 gets loaded with the Hornady 200 gr +p XTP. I’m not comfortable with the heavier loads in this gun, as I do want some hope of expansion. At about 940 fps, I’m hoping for it, but not expecting it too much. I really doubt I’ll get any though with the 230 gr loadings; they’re too slow.
I abandoned the lightest and fasted crowd because I worry that these rounds, though likely to expand, will stop before they get too deep to do much damage. If your adversary is 6’2" and 225 lbs, or 5’10" and 225 lbs for that matter, of the eight or nine or inches of penetration you might get with a light-and-fast, 1/2 of it will be fat and/or muscle. Take a look at the guys who are or who have been in prison (something like 75% of all crimes are perpetrated by ex-convicts), few of them are small men. The shock value of a light-and-fast will be lost on disrupting blubber or penetrating layers of muscle. I want something that will get through the fat and muscle, and still have enough left to get to the vital organs. A light-and-fast is less likely to do that. Here, far from disagreeing with Chuck Taylor, I’m with him.
--------------------------------------------------------------------------------
Why 10?
So let’s look at my reasons for switching to the 10mm, and my reasons for thinking it is THE best cartridge around.
I am approaching this article, and my home defense, with the intent that the ammunition I choose will at least have the possibility of expanding in an adversary. For those of you who carry .45 ball or JSPs because you trust no round to expand, and hence believe there is no point in trying, I give you your due. There is no popular self-defense round which makes a bigger hole than the .45 ACP. A 10mm auto FMJ, or JSP cannot make a hole as big a .45 ACP FMJ or JSP. The 10mm auto can’t win here. But if expansion is important to you, or energy, or momentum, or velocity or bullet weight variety, 10mm beats .45 ACP nearly every time.
Please note the attached charts.
I have attempted to give as close as possible an apples to apples comparison when it comes to the guns. I own a Colt .45 ACP with a 5" barrel and a Colt Delta Elite with a 5" barrel. These are the primary test guns. Below this chart is the backup test guns chart: a borrowed Glock 30 was used, and my personal Glock 29.
Colt DeltaElite 10mm 5” bl.
MFG
Wt
Type
MFG vel
Velocity
Energy
Power
Factor
Cor Bon
180
JHP
1175
1268
643
228
Georgia Arms
155
JHP
1375
1346
624
209
Hornady
155
XTP
1265
1335
613
207
Cor Bon
150
JHP
1325
1351
608
203
Hornady
180
XTP
1180
1230
604
221
Winchester
175
JHP
1290
1239
597
217
Pro Load
180
GDHP
1200
1207
584
218
Cor Bon
180
JSP
1300
1206
583
217
Norma
200
FMJ
1200
1140
578
228
Cor Bon
200
FMJ
1200
1134
571
227
Black Hills
155
JHP
1300
1278
562
198
Cor Bon
165
JHP
1250
1236
560
204
Cor Bon
135
JHP
1400
1357
552
183
PMC
170
JHP
1200
1198
542
204
Hornady
200
XTP
1050
1099
537
220
CCI
200
FMJ
1050
1056
496
211
PMC
200
FMJ
1050
1039
480
208
Federal
180
JHP
1030
1014
411
183
Federal-HS
180
JHP
1030
968
375
174
Colt .45ACP 5” bl.
MFG
wt
type
MFG vel
Velocity
Energy
Power Factor
Cor Bon
165
JHP+P
1250
1255
577
207
Remington
185
JHP+P
1140
1131
526
209
Hornady
200
XTP+P
1055
1048
488
210
Cor Bon
200
JHP+P
1050
1029
470
206
Pro Load
200
GDHP+P
1030
1017
459
203
Cor Bon
230
XTP+P
950
944
455
217
Remington-GS
185
JHP
1015
1001
412
185
Federal
185
JHP
950
993
405
184
Remington-GS
230
JHP
875
873
389
201
Federal
230
JHP
850
864
381
199
Federal-HS
230
JHP
850
859
377
198
CCI
230
JHP
830
855
373
197
Winchester-ST
185
JHP
1000
953
373
185
CCI
230
FMJ
835
823
346
189
These are all the loads I’ve tested in my guns, sorry if yours isn’t here.
--------------------------------------------------------------------------------
Energy Junkies
If you’re an energy junky, which I have found a surprising number .45 ACP lovers are, then take a good hard look at these charts. Even those of you who love the high velocity, high energy and lightweight .45 rounds need to look at the numbers the 10mm puts up. As a former member of your camp, certainly the .45 ACP 165gr JHP from Cor Bon is a screaming hot round, with lots of penned up energy to dump in the bad guy. 577 foot pounds of energy is impressive, indeed. But the 10mm wins the energy battle. The .45 ACP has but one loading, the 165gr, that reaches these energy levels, and about three different makers of this loading. With the 10mm, I have chronographed fully 6 loads (and there are more out there!) in four different bullet weights that BEAT the energy levels of the 165gr .45 ACP loads by a minimum of 20 foot pounds of energy each: some by substantially more. And these loads give a wide range of bullet weights, from the screaming hot 150gr loads, to the hard pounding 180gr Cor Bon. If you’re into light loads that create big stretch cavities you should be looking at the 10mm, not the .45 ACP or the .40 S&W or even the .357 magnum!
--------------------------------------------------------------------------------
Momentum Maniacs
Many of the 10mm loads beat the .45 here too. Momentum basically aids in penetration, so rounds with high numbers here should get good penetration, provided that they don’t expand too quickly, like the 165gr .45 ACP loadings would. (Though I use “Power Factor” in place of momentum the charts, it’s basically the same thing. So, a high power factor load will generate an equivalently high momentum number.) Still, the 230gr .45 ACP from Cor Bon has a 217 Power Factor, the most in the caliber. And keep in mind this is a +p load. Your run-of-the-mill 230gr have a Power Factor of around 199. Yet, the 10mm has half a dozen loads which meet or exceed this Power Factor. If you like good penetration potential, why aren’t you shooting the 10mm?
--------------------------------------------------------------------------------
Bullet Weight
Another area where the 10mm beats the .45 ACP, the 9mm, .40 S&W, .357 magnum or any other cartridge is in the department of bullet weight variety. Think about it, the 10mm has bullets for defensive use alone in weights of 135, 150, 155, 165, 170, 175, 180 and 200 grains. That’s eight weights! Plus the 190gr, and 220gr weights which are NON-JHP and for other shooting applications. The .45 ACP has 165, 185, 200 & 230 grains – four different weights. 9mm has 90, 115, 124, 125, 127,130, 135 & 147 – that’s eight different weights, but I’m being nice by separating out the 124, 125 and 127gr loads. .40 S&W has weights of 135, 150, 155, 165 & 180, that’s five different weights. .357 magnum has 110, 125, 140, 145, 158 & 180. That’s six, but I wouldn’t recommend using the 180gr load for home defense – if you want heavy in .357 magnum, use the medium wt. loads. I like the 145gr Winchester Silvertip. So you see, the 10mm has a weight, and a load for every one.
--------------------------------------------------------------------------------
Expansion
Only the lighter weight .45 ACP loads are going to open up in an adversary with any reliability. This problem is compounded in the short barrel .45s. I don’t have sophisticated labs, nor the money to do such tests, but I’ve got meat, and big phone books to soak, and old clothes to put over this stuff, and here’s what I’ve discovered: .45s work well in all bullet weights out of a five inch barrel. But shorten it to Glock 30/36 length, and the heavier bullets don’t want to expand. Loser bullets that I’ve tested in a Glock 30 are some of the most respected in the .45 crowd. Sorry, these are my results, and I’m only sharing them with you. The 230gr crowd: Federal Hydra-Shok barely expands, Federal JHP Hi-Shok doesn’t expand; 200 gr. +P Pro Load (a Gold Dot HP bullet) shows minimal expansion, and was a huge disappointment to me. 185gr Remington Golden Saber opens a bit, but shoots the unexpanded core forward, leaving the jacket behind. But the full power 10mm loads are all generating upwards of 1200 fps, well above the expansion threshold for most any decent hollow point. Perhaps only the .357 magnum achieves such results, and the new .357 SIG, but we go back to dealing with some lighter bullets, and lower momentums.
) 
