Picked this up from a small auction a few weeks ago. I've been wanted to add an M1903 and took a gamble on this Mark I. I actually tossed in a low ball bid the day before and walked away. A bit surprised to find I had won it.
Anyhow, the Mark I is an interesting variant of the M1903, modified in a number of ways to accommodate the "US Automatic Pistol Cal .30 Model of 1918", aka the "Pedersen Device". The Pedersen Device was an insert that substituted for the standard bolt to generate a semi-automatic rifle firing an over-sized pistol round for rapid fire in trench clearing warfare of WWI. By the time these were ready to be deployed in numbers, WWI had ended.
The modifications of the rifle that constitute the Mark I designation are a cutout in the left receiver rail that served as an ejection port for the spent cartridges, a corresponding notch in the stock, a special magazine cutoff, and a special sear/trigger assembly. Most of the Mark I rifles were converted back to M1903 configuration (except for the markings and receiver rail cutout) in the 20's. My example is missing the trigger and sear but has the other parts. I will not be picking up a Pedersen Device, as most were destroyed 90 years ago and the few survivors fetch 30-50K, or somewhere in that stratospheric neighborhood, depending on accessories, magazines, condition, etc.
The stock has seen some hard use and the bolt is an earlier 90 degree type, rather than the slightly swept back bolt handle that would be appropriate for the later manufacture of the Mark I's. The barreled receiver and stock is likely original, as well as the magazine cutoff. Other parts beside the bolt appear to be replacements. It's interesting that whatever refurbishment that was done skipped the magazine cutoff replacement.
The bore is very good, .300 across the lands, as you can see from the muzzle erosion gauge. It's a very nice shooting rifle with its narrow blade front sight. It's just a nice bonus that it's a bit more collectible than the average M1903
UNDER THE HOOD