the Garand's action can be damged by using unsuitable powders & loads, due to the pressure curve being different than that used in the original GI ball loads that only was loaded with IMR 4064, IMR 4895 powders....
Some have reported okay loads with the variable gas plugs... but... Your rifle was made at least pre 1955 or so & possibly 15 years older than that... original parts of the proper type are getting harder to find & very expensive even if you can locate them... It would not be worth it to me to chance harming my IHC postage stamp or Type II NM using a load that is saving me just a few cents per bullet .......It is up to you, it's your rifle... but to me it's a foolish idea.
Don't blame you, most shooters don't change. I liked them because I could take the blinders off and use allot more powder/bullet combo's that the standard "you have to use this or bad things will happen/4895 or nothing/yada-yada-yada.
For those that want more out of their garands, that plug will bring you to the promised land. Accuracy is the huge improvement with the adjustable plugs. Being able to fine tune loads is huge and the ability to get the garand to cycle with loads that would never happen with the traditional setup is an added bonus.
Standard setup:
It's called timing, the gas block has a set hole to allow a specific about of pressure/gas back to operate the op rod. The op spring has to be a certain strength for everything to work correctly. The end result is a very narrow window the ammo has to fit into to make enough pressure to cycle the rifle but not enough to harm it. Then the rifle has to like that load or accuracy suffers or the op rod isn't just right or the op spring is a little weak. The end result is the timing is off enough to affect accuracy.
The adjustable plug:
Only a fool could damage a garand while using 1. I've always said firearms are not for everyone. If things like turning a screw are complicated or moving a switch (safety) is hard to understand then those people should avoid firearms. For people that know how to turn a screw, install the adjustable gas pug and turn the gas screw all the way out. Load and shoot a round. There you just made the garand into a single shot. Give the screw 1/2 turn in and shoot another round. Nothing?? Keep testing with 1/2 turns and shooting 1 shot at a time. You will get to the point that there will be enough gas to start to move the op rod/bolt. Another 1/2 turn and the rifle will cycle but the brass will be laying at your feet. Give the gas screw a 1/4 turn at that point and the spent brass will be laying in a pile 3ft away. Cave man simple for anyone that understands how a screw works.
Extremely hot loads, big deal!!! You can dial the rifle in so the action barely functions. Extremely light loads, absolutely!!! Heck take your favorite coated/cast bullet and load them to 1600fps using your favorite pistol powder and adjust the plug until the garand cycles flawlessly.
With the adjustable plugs you can reload for your garands for accuracy 1st Then simply adjust the rifle for function.
With standard garands you have to reload for proper cycling/function 1st then try to find an accurate load within the small window of that functioning load.
I do find it funny that it's doom and gloom to even think about having an adjustable gas system on a m1 garand. God forbid something might happen!!! But no one bats an eye if their on a m1a1/m14. Go figure!!!!
Then you got people like brownell's selling them and putting things like this in their ad for a sales description.
Vented steel design changes cycle time by letting you adjust the gas volume in the cylinder. Quick adjustment of vent size with integral set-screw; eliminates changing screws for different vent sizes. Reduces battering on op rod, bolt lugs, receiver and trigger group. Available for M1 Garand and M1A.
Gee, who would want to reduce battering of their op rods and other assorted pieces and parts????
). I think I'll try it with the expanded gas plug in and if it doesn't operate the action, put the original gas plug in and try it. I doubt I could overpressure it that way. This is just a feasibility experiment and I hope within the ball park. If it hits the target we can see how to compensate.
