Earlier when XBrad outlined the different types of cannons, he tasked me (Craig) to trace the history of the types. Many of the calibers we see in use today date back to standardization decisions in the 1930s or even earlier. X Brad lead into this a bit, discussing the history of the famous “105” howitzer. The 105mm M2 gun came from a requirement placed after analysis of World War I experiences. Given that story line, I’ll pick the somewhat arbitrary start point of the weapons in the US Army inventory around 1914.
The Spanish-American War was in many ways a wake-up call for the Ordnance Department of the US Army. The Army went to Cuba and the Philippines with an inventory which featured breechloading guns. But such guns, like the 3.2-inch gun (above), 3.6-inch guns, 3.6-inch field mortars, or the lighter Hotchkiss mountain guns, had a poor showing against Krupp guns used by the Spanish. At that time in history the world was trying to catch up with the benchmark set by the faster firing French 75mm Model 1897 gun. But the French were not selling that marvel on the open market. What gave it such an edge? Well, sharp-eyed redlegs will notice the gun pictured above has no recoil mechanism. So just like the old Civil War pieces, every time it was fired, the gun crew had to readjust the piece. The French considered the recoil mechanism, along with the innovative breech block system, a state secret. In addition, the old 3.2-inch gun used separated ammunition with bags of black powder.
Following the Spanish-American War, the US Ordnance fielded improved equipment in almost every category. Some backstory about the Ordnance Department is of note here. In 1901 General William Crozier assumed the office of Chief of Ordnance. Although Crozier spent most of his career oriented towards seacoast defenses. This was in no way out of step with the Army’s priorities of the day. For about a century prior to World War I (arguably save a brief interlude known as the Civil War), the US Army’s most important mission was defending the nation’s coast. The Ordnance Department tended to be conservative in technical approach, and were reluctant to change designs based on feedback from the field. Some historians over the years have been critical of Crozier’s approach, but during his tenure as chief (1901 to 1918) a number of outstanding weapons emerged. Just to name a few – the M1903 rifle, the M1911 pistol, the M1918 BAR, the M1917 Machine Gun….
To solve the field gun requirement, the Ordnance officers first replaced the 3.2-inch gun. Following the lead of the British Army, the US purchased rights to a field gun from the German Erhardt company. The Erhardt 3-inch gun featured a pneumatic recoil system and fixed ammunition. The gun ranged out to 8,500 yards. Like the British Army, which purchased a similar piece as the Quick-Firing 15-pdr, the Americans considered the Erhardt a temporary solution while awaiting domestic weapon developments.
With a few modifications to suit American tastes, the Ordnance department standardized the gun as the M1902 with production starting at Rock Island Arsenal. But funds were short and only a limited number hit the field. But enough were produced to outfit the regular Army. The M1904 and M1905 had small improvements, but most parts were interchangeable.
Limbered up, the M1902 resembled its Civil War forbears. This is due to the pole trail and spoke wheels. The pole trail limited elevation to 15°. And of course in the field horses (or some of those new tractor contraptions) pulled the gun. The gun on carriage weighed 2,400 pounds.
While some shortfalls emerged, the field artillery found the M1902 at least acceptable, if not outstanding. The gun served well by all accounts. Indeed, one of them still serves the “Aggies” of Texas A&M.
In 1906-7, the Ordnance Board, deviating somewhat from previous experiences, accepted input from the field regarding artillery (perhaps “had to accept” after some pressure from above is one way to describe it). Input lead to several “stable-mates” for the 3-inch gun – a 3.8- and 4.7-inch field guns along with 3.8-, 4.7-, and 6-inch field howitzers. In addition a 3-inch mountain howitzer appeared to supplement the 2.95-inch Vickers mountain gun then in service (I’ve mentioned those in passing in a post on my blog, and will return to discuss in detail later). In September 1907 a series of tests evaluated various artillery systems against redoubts and entrenchments (Yes… the Americans were thinking about fighting in trenches long before the Great War). As with many similar tests over the years, the army compiled many lessons learned backed with empirical data, but lacked the funds to translate conclusions into equipment purchases.
The 3.8-inch M1908 howitzer, on paper at least, offered useful performance figures. Firing a 30 pound projectile to a maximum range of 6,100 yards, the setup weighed 3,000 pounds. Line diagrams from manuals show a compact design with recoil system mounted over a short barrel. The box carriage trail allowed the howitzer to elevate up to 45°. But few of these weapons rolled off production lines, and fewer still were issued. The 3.8-inch howitzer paired well to the 3-inch gun, and might have been a great complement at the divisional level in France.
The 4.7-inch Model 1907/08 howitzer reached limited production also, but although several survivors exist today, very limited details exist about the gun’s service. Manuals credit the gun with a 7,000 yard range at 40°. But increased caliber raised the weight to 4,000 pounds, perhaps making the weapon only a marginal improvement over the 3.8-inch howitzer. Similarly the 3.8-inch Model 1907 field gun failed to find a niche. It weighed double that of the 3-inch gun, but offered only a few thousands yards more range with a 30 pound projectile.
The 6-inch Model 1906/07 looked good on paper. Weighing 7,200 pounds, the 6-inch howitzer was lighter than contemporary French and British weapons in its class. But in 1917 the Army deemed its 9,000 yard range with a 90 pound projectile insufficient for the war in Europe. As a result the Army shelved this promising howitzer, opting for French and British designs.
Saving the best for last, the 4.7 -inch M1906 field gun (some list the gun as M1907 or M1908, which were just improvements on the basic design) actually measured up rather well with contemporary European guns.
Although the gun weighed 8,700 pounds in action, it threw a useful 60 pound shell to 11,000 yards. This gun fit into the “medium” category of field artillery, working at the corps level. But while successful, like the other field artillery types in the US inventory, only a few were produced by 1914.
Thus as the world entered the “great war” the US had at least a start towards modern artillery equipments. While lacking howitzers, perhaps more so due to institutional preferences, the field artillery possessed a couple of capable field guns in the 3-inch and 4.7-inch categories. But in 1917, the rush to equip a force to fight in France would overtake these otherwise capable weapons.