Talk:90 mm gun M1/M2/M3

Most powerful AT gun?
This article claims the 90 was the most poweful AT gun on the allied side. However Guns vs. Armor suggests that the 17 pounder outperformed it until the post-war introduction of the HVAP M304 rounds, and then only marginally compared to the British APDS rounds. Anyone have any additional info? Maury 01:22, 19 February 2007 (UTC)


 * Nothing like a timely response right?
 * The 90 mm was very rarely employed as a towed AT gun, but the 17 pounder was commonly used in that role so I think the comparison is almost meaningless.
 * As for vehicle mounts, the 17 pounder is better unless 90 mm HVAP ammo is included in the comparison. 17 pounder APDS was the shizzle. DMorpheus (talk) 19:44, 7 January 2009 (UTC)


 * The 17 pdr cartridge actually contained a larger propellant charge than the 90 mm Gun M1/M2/M3.


 * Propellants are not all the same. The 17pounder used inferior grade of propellant producing only 1,150 foot tons (3,110 kilojoules) of muzzle energy versus 1,310 foot tons (3,550 kilojoules) for the early M82 APC loads and 1,460 foot tons (3,960 kilojoules) for the later loads.

There was also a "T-8" version of the 90mm. It was a conventional split-trail design, no muzzle brake, minimal flat armor shield, a dedicated anti-tank gun. Two of these guns were emplaced on a hill in Korea that commanded a North-South potential assault route. I was there, but I have no idea where it was geographically. They were manned by a small group formed for the purpose: a provisional "Yoke" battery of the 21st AAA AW BN (SP), which was nominally an M-16 equipped "Quad 50" unit of the 25th Infantry Division. These guns must have been uncommon, as the "T" designation would imply. I was told that there was a third gun stored in a rear area for parts. They were extremely effective. Mike —Preceding unsigned comment added by 68.6.186.244 (talk) 02:50, 23 April 2009 (UTC)


 * The 17 pdr cartridge actually contained as much propellant charge as the cartridges of both the 90 mm and the 75 mm Gun M2/M3/M6 combined. — Preceding unsigned comment added by 95.149.173.13 (talk) 13:16, 12 March 2017 (UTC)


 * The 17 pdr had an 8 pound propellant charge per Ian Hogg or 9 pounds per other sources. The 90mm was loaded with 7.3 pounds (of a higher quality propellant than used in the 17 pdr) while the 75mm was loaded with 2.16 pounds: 7.3 + 2.16 = 9.48 pounds.

The issue with more powerful" is defining "powerful" - the 90mm generated more energy than some but not all Allied cannon (Soviet guns come to mind) but that does not equate to greater armor penetration. There is the matter of frontal area which retards penetration with the 90mm having 39.5% more area than the 3-inch (76.2mm) caliber 17-pounder for example. As far as numbers go, they tended to lie - the effectiveness of a round against armor was not indicated by numbers but rather by tests. As far as tests go, it is very easy to find amateur analysis by people slanting data as they prefer. For example, the U.S. set up tests to see what various cannon could do and the 17-pounder's APDS with a theoretical rating of 10.5-inches (at 0 degrees) was unable to penetrate the front glacis of a panther which was 80 millimeters at 55 degrees, roughly equivalent to 140 millimeters or 5.5 inches. Neither could the U.S. 76mm/3-inch HVAP with a paper rating of around 8-inches. Not enough was known about tungsten cored shot to design effective projectiles and as such they suffered extreme losses in effectiveness against sloped armor. The 90mm M77 AP could penetrate said slope at 500 yards or less and the 105mm howitzer HEAT round as well, but within the limits of accuracy. Thus the design/nature of the round counts. BUT (and this is a big BUT and the point of what I mean by "amateur analysis by people slanting data as they prefer") the bones of the test was that the people performing it were trying to determine FIRST ROUND effectiveness against THE GALCIS of an UNDAMAGED Panther. They discounted several hits that penetrated because they were not a "fair hit" - they struck where previous projectiles had, impacted weak welds, struck the lower nose plate, etc. The takeaway was that even if a round failed to penetrate, it could weaken (physically dmage) the armor such that successive hits would have a better chance of penetrating - and the more powerful the gun, the weaker the armor became. The overall analysis by some outsiders has typically been "twisted" because in the end it would not matter why a penetration occurred only that it did. This is as bad as the obsession with tank-versus-tank warfare (by people with a very poor overview of what it really was like) and the children constantly arguing "My gun is bigger than yours.".

Standard AA gun?
The article mentions the M2 version as becoming "the standard weapon from May 13, 1943", a date which I have seen in other sources as the date that the weapon was standardized. There is, however, a difference between a gun (or other weapon) being standardized and a gun become the standard weapon of its class (implying in this case that it was to be the most common 90mm gun in service), something that would seem to be belied by the fact that most photos of 90mm guns from World War II are M1 or M1A1 versions.--172.190.37.86 (talk) 00:18, 17 March 2012 (UTC)
 * On a somewhat related note, did the M2 version even make it overseas during the war? I've seen dozens upon dozens of wartime photos of the M1A1 actually being used, but can't recall any of the M2.--172.190.176.19 (talk) 00:09, 23 January 2013 (UTC)

What does it all mean?
Could somebody who knows about these things please translate, at least on first mention, the 'Surviving Examples' section, because this Limey and I suspect many other non-Americans, do not know what is meant in many instances; e.g. "One AAA at NTC, Fort Irwin, CA post museum" I think means : 'One anti-aircraft artillery (vehicle or piece?) at NTC (dunno, National Training Centre?) Fort Irwin, California post museum'.

There are many others

RASAM (talk) 21:14, 3 July 2013 (UTC)

Shell is 23.6 inches in length?
I'm not clear, is this overall length, or the length of the shell itself? It says "it fired a 23.6in shell up to 60,000ft", but 23.6in seems very long for a 3.5in caliber shell. I'd assume it was a mistake, except that it also seems quite short for an overall length, for a gun meant to reach high velocities and altitudes. Down below in the table it again lists the "M1A1" ammo as "3.5in x 23.6in", and then lists several others as "complete length", giving lengths closer to 35 inches. I could presume this means the initial entry is for shell alone, while the other three are for complete round? Could we perhaps get some clarification in a few places? Because I can assume that's what's trying to be said, but I don't know, and it's equally difficult to believe that there is only 11 inches of shell space available for powder charge; I would have guessed it was more like a 1:3 ratio of shell to powder, not the reverse. But that seems to be what this article is saying, that the shell is 23.6in long, and the overage complete round is 35in long. Do that math, that leaves a space of less than 11 inches to cram all the propellant in. The other possibility is that the 23.6in is actually the overall length of the original shell, and the later rounds are considerably longer, for whatever reason. If that is the case, then it is not true that the gun "fired a 23.6 inch shell to 60,000ft", because most of the length stayed on the ground.AnnaGoFast (talk) 06:21, 2 February 2018 (UTC)
 * They are referring to the specification of "(90 mm × 600 mm)" which refers to the cartridge case not projectile. Much of the article is of this date (03/29/2021) poorly written, about as amaeturish as can be. For those who want data: TM 9-1901 pages 162, 163, 164. The length of the M82 APC projectile was 16.19 inches (41.1 centimeters), M77 AP was 10.0 inches (25.4 centimeters), and M77 AP was 16.37 inches (41.6 centimeters). The loaded rounds were 38.24 inches, 32.75 inches, and 37.44 inches. The cartridge case itself was 23.70 inches (602 millimeters not 600) overall. — Preceding unsigned comment added by 2600:8804:9F03:200:B1C6:CC72:2F00:409 (talk) 16:15, 29 March 2021 (UTC)

Please get over the obsession with antitank warfare, it is clouding history
To quote the current article (3/29./2021): "Like the German 88 and the British QF 3.7 inch AA gun, the M1A1 found itself facing tanks in combat, but unlike the others it could not be depressed to fire against them. On September 11, 1942, the Army issued specifications for a new mount to allow it to be used in this role, which resulted in the 90 mm M2, introducing yet another new mount that could be depressed to 10 degrees below the horizontal and featured a new electrically-assisted rammer. It became the standard weapon from May 13, 1943."

The U.S. entered Morocco in November 1942 and hence the decision to improve the 90mm's depression was not based on having met German tanks. Nor was it based on antitank use. To quote [The American Arsenal, Greenhill Books page 194] :“In July 1941 it was decided that all mobile antiaircraft weapons should be dual-purpose weapons that could be fired against both aerial and ground targets when the mount was on wheels. This was impossible with the M1A1 mount, since it was necessary to remove the wheeled bogie and emplace it with outriggers extended before opening fire. It was also decided that the 90mm gun should be capable of use against motor torpedo boats and other small craft, a function that required a greater depression than 0° which was the minimum of the Mount, M1A1.” Ian Hogg repeats than the decision as such on page 126 of [British and American Artillery of World War Two]. — Preceding unsigned comment added by 2600:8804:9F03:200:B1C6:CC72:2F00:409 (talk) 17:00, 29 March 2021 (UTC)

Production Numbers
The sidebar states that 133,833 90mm AA guns were produced between 1940 and 1945. Quite frankly, this number seems impossible, and I don't see a citation.

At 8 men per gun crew, this implies that the US assigned more than a million men to operating 90mm AA guns during WW2. That the US, with air superiority, built 6x as many heavy AA guns as Germany (under constant heavy bomber attack).

Elsewhere online, I've seen claimed numbers of US 90mm AA guns as just under 10,000, which makes more sense to me. For reference, the US built 10,000 105mm light howitzers, 10,000 155mm medium howitzers, etc. I'd like to see a citation for that 130K figure. 75.75.185.92 (talk) 21:31, 6 February 2023 (UTC)