You can carry the M48 around cocked for the day of hunting/shooting without any problems or damage to the spring. Most of us shoot our "springers" quite a bit when we carry/hunt with them so s "day" cocked is a pretty long time. Most of us don't leave them cocked over night though. You can uncock the M48 without firing it and leave the pellet in the chamber if you want to. I do that on my springers, including my M54, all the time. Thus is is easy to just cock the rifle when a target of opportunity presents itself.
To uncock; grasp the barrel as you normally do to cock it and break the action pulling the barrel down in the "cocked" position so you can feel spring compression. The butt of the rifle should be braced against the body where it is when you normally cock the rifle. Hold the barrel solidly with the spring compressed and release the safety and pull the trigger easing the barrel out until the bear trap engages. Let go of the rifle ith the trigger finger hand and release the bear trap (keep holding the spring tension with the barrel) and ease the barrel out to the extended position. A few practice times and it will come easy. The rifle is now uncocked but has a pellet loaded. All you need do to fire is cock the action, line up on the target, release the safety, aim and smoothly pull the trigger.
Extensive tests have been conducted because this is an oft asked question. The test results showed no damage or weakening of the spring when left cocked for for as long as several weeks. Don't worry about it. However, all springer mainsprings will take a "set" after a thousand or so shots have been fired. This is normal and should not be confused with the spring weakening.
Larry Gibson
