Here is a post that I picked up some time ago that proves that the .45 is not always superior in all situations. As a matter of fact I often wonder wether 1/10 of an inch in diameter is really all that superior when comparing the 9mm to the .45acp. As you will see this test is nothing new, it was conducted way back in 1948. I think that the low penetration factor of the .45 was a real concern to many of the worlds militaries and that the 9mm's higher velocity and penetration was a real plus when using the sub-machine guns. Interchangability between a pisol and sub-gun of the same caliber was also a factor. In other words why have a .45 cal. pistol (even if it was surmised to be slightly superior in a pistol) and a different caliber in a sub-gun when it wasknown that the 9mm was the superior sub-gun caliber in terms of flatter trajectory, superior penetration, and lower recoil and therefore more controllability.
Here is the 1948 test
I actually posted this in April of last year (and commented then that, although it really only constituted penetration testing - not "knock-down" or "stopping" power, I nevertheless found it most interesting!
Grant Rombough, Medicine Hat, Alberta
Here's the entire previous post:
I just HAD to respond to this thread by quoting a 1948 Springfield Armory report on some pentration tests they conducted using an Inglis HP, with a Colt .45 1911A1 as a sort of "control" pistol. The report is quoted below (verbatim) from pp. 178-9 of Clive Law's new book, "INGLIS DIAMOND: The Canadian High Power Pistol". Sorry about the resulting length of this post, but I trust many of you will find it absolutely fascinating. (Now I know that "penetration" does not equate with "stopping power", but I certainly found the comparative performance of the military .45 Ball ammo surprising!)
Here goes:
SPRINGFIELD ARMORY
RESEARCH AND DEVELOPMENT DIVISION
MEMORANDUM REPORT SA-MR 20-2100
L O Spaulding/lv
24 August 1948
SUBJECT:
Effective Penetration Range of 9mm Parabellum Ammunition.
OBJECT:
To determine the greatest range at which the subject ammunition will penetrate the M1 helmet.
SUMMARY:
M1 helmets were fired at using different 9mm ammunition to determine the greatest penetration range. A Canadian 9mm Parabellum ammunition having a velocity of 1250 f/s penetrated the M1 helmet at 130 yards, which was further than any of the other ammunition tested.
REFERENCE:
Project TS2-7875-2024 J O 7875-6160
MATERIAL:
1. Weapons
a. Browning FN 9mm Pistol, HP Inglis-Canada, Serial Number 8T2367
b. Colt Automatic Pistol, Cal .45, 1911A1, Serial Number 1651407
2. Ammunition
a. Special 9mm Parabellum cases and Cal .38 S&W Special Bullets (Metal clad, 158 grains) and loaded to a velocity of 850 f/s.
b. Winchester 9mm Parabellum, 116 grain bullet, Lot WRA22026, 1,150 f/s instrumental velocity at 53 feet.
c. Cartridges, Ball, 9mm M1, 116 grain bullet (Parabellum) (Code T2CAB) Lot DIL- 617 (Canadian) 1,250 f/s instrumental velocity at 53 feet.
d. Pistol Ball Cal .45 M1911, Lot E C S25250.
3. M1 Helmets
4. Outdoor range facilities
PROCEDURE:
An M1 helmet was placed on top of a stake, back of which a target was set up to facilitate aiming and to lend support to the helmet. The 9mm Canadian pistol was then fired from a muzzle and elbow rest at the helmet. In the event the helmet was pierced, it was moved away from the shooter 10 yards and the procedure repeated until failure to pierce the helmet resulted. This procedure was followed with the special 9mm ammunition and with the high and low velocity 9mm ammunition. A similar test was run using a Colt Cal .45.
RESULTS:
1. The special 9mm Parabellum case with a Cal 38 S&W bullet penetrated the M1 helmet at 50 yards, but not 60 yards.
2. The Winchester 9mm Parabellum (1,150 f/s velocity) penetrated the M1 helmet at 120 yards, but not at 130 yards.
3. The Canadian 9mm Parabellum (1,250 f/s velocity) penetrated the M1 helmet at 130 yards, but due to lack of longer range facilities was not fired beyond this point.
4. The Cal .45 ammunition penetrated the helmet at 30 yards, but not at 35 yards.
CONCLUSION:
It is concluded that the Canadian 9mm Parabellum ammunition with the 1250 f/s velocity, had a longer range penetration power than any of the other ammunition tested.
Prepared By: L O Spaulding, Ordnance Engineer
H F Hawthorne, Ordnance Engineer
E W Hopkins, Head Ordnance Engineer
: