I recently got my grubby hands on a big pile of gun-related documentation (thanks, Mike!), and one of the items that jumped out at me while looking through it was a 1949 report on the T25 rifle, printed by the Springfield Armory R&D department.
To recap briefly, by the end of WWII the military had decided that the M1 Garand needed to be updated, and they had John Garand working hard on a version (designated the T20) that used 20-round box magazines and was capable of full-auto fire. The urgency of that project evaporated with Japan’s surrender in 1945, and before long the concept of a new light rifle with a shorter cartridge (the T65, which would eventually be formalized at the 7.62mm NATO) took hold. US Ordnance put an engineer named Earle Harvey in charge of studying all the available small arms technology and developing an ideal “light rifle” for use with this new cartridge.
Harvey’s creation was the T25, and it really was a pretty good rifle. It used a modified version of the M1’s gas system (the same basic system would eventually be used on the M14) and a tilting bolt reminiscent of the Bren. With careful lightening and judicious use of some aluminum parts, it came in at a mere 7lbs, too. It performed well in early tests, and 50 were ordered for more extensive testing. Twelve of the T25 rifles were delivered in January of 1949 (having been built by Remington), and by the end of that year Springfield had also printed this manual on the weapon:
In addition to providing instructions for complete detail stripping of the rifle, the manual revealed a couple details I had not been aware of regarding the operation of the T25. For one thing, it was set up to fire from a closed bolt in semiauto and from an open bolt in full auto. That’s a good idea, given the necessarily light barrel and the operation plan to use the gun as a replacement for both the M1 and BAR. What is a bit more surprising is that the bolt release was integrated into the trigger, like some much earlier designs (you can see this mechanism in action in my videos on the ZH-29 and Farquhar-Hill).
Bascially, the manual of arms for a system like this is (starting with the bolt locked open on an empty mag): remove the empty mag and replace it with a loaded one (the bolt stay open when the mag is removed). Confirm that the selection is on semi, and pull the trigger once. This releases the bolt, which chambers the first round from the new mag but does not fire. Then pull the trigger a second time to fire, at which point the rifle operates just like you would expect, loading a new round and waiting, closed, for the next trigger pull. If the selector is set to full auto, things work a bit differently. In full auto, the rifle fires from the open position, so the first trigger pull when locked open and a full mag inserted will fire, and continue to fire until the trigger is released – at which point the bolt will catch in the open position and wait for another trigger pull.
This type of mechanism seems pretty crazy today, with all of our training to keep away from the trigger until actually ready to fire. From a military perspective, though, it’s not necessarily a bad idea. By using the trigger, the design allows the bolt release control to be removed entirely, which certainly simplifies the controls. If a soldier in combat shoots his rifle dry and has to reload, he will naturally be going back to the trigger, so using it as the bolt release is easy to train. The bolt can still be alternatively closed by removing the magazine entirely (thus disengaging the holdopen mechanism) and racking the charging handle. The trigger release idea certainly doesn’t fit with modern range safety practices, but in its 1940s military context I think it was arguably a pretty good decision. It simplifies handling and training and removes a lever on the outside of the gun all without making the system more complex.