Driftless
Donor
The US could have done without the 4.5" gun. This was a rework of the last in the series of 4.7" guns the US Army experimented with from 1900 through the 1930s. Circa 1941 the cannon was redesigned with the smaller bore and modified breech to make use of British 4.5" ammo. I corresponded with a US enlisted man who worked in the Fire Direction Center of a battalion of these weapons. He told me they invariably fired the entire battalion of 12 guns on a single target or aim point. After looking at the ammunition effects tables & the size of the explosive charge in the HE projectile its clear why. The ammo was underpowered compared to the US 105mm & 155mm cannon ammo. While the 4.5" gun had excellent range it had little destructive power. Comparablly the effects tables show 3-4 of the US 155mm guns, the Long Tom, had as great a destructive power on a target as a dozen or more of the 4.5" guns given the same time length of fire mission.
Another was the 3" AT gun. This was a version of the 3" gun used in the M10 Tank Destroyer, but mounted on a single axle towed carriage. Compared to the 57mm AT gun the 3" had poor tactical manuverability & was even worse compared to the M10, M18, & M36 TD vehicles. The towed 3" ATG was of course much more vulnerable to light counter fires like MG, mortars, light field artillery, and even tank guns.
With your knowledge of artillery in US WW2 use; what's your assessment of the 57mm Gun M1 (Ordnance QF 6 pounder) and the 75mm pack howitzer M1/M116? With the 57mm, was it mostly the US got caught behind the development curve and that weapon was the superior available choice at the time?