M14: Should I polish the gas piston while I have everything apart?
- Thread starter Kwattro
- Start date
I know some people LIGHTLY oil the gas piston but I dont think alot of members here recommend it.
I did it myself, but I havnt tested it long enough to see any differences.
Just make sure you clean the gas system well if you do
I did it myself, but I havnt tested it long enough to see any differences.
Just make sure you clean the gas system well if you do
Ardent
CGN Ultra frequent flyer
The M14 gas cylinder and piston is a dry system, adding any sort of lubricant allows carbon deposits to stick and cause far more damage than if left dry, even in small amounts. While the result will not be catastrophic by any measure, your gun will last longer and was designed for a dry gas cylinder.
As for polishing it, there's really no point, if your guns cycles and feeds fine, why bother enlarging tolerances and messing with things?
It's really a "if it ain't broke don't fix it" situation.
As for polishing it, there's really no point, if your guns cycles and feeds fine, why bother enlarging tolerances and messing with things?
It's really a "if it ain't broke don't fix it" situation.Ardent said:The M14 gas cylinder and piston is a dry system, adding any sort of lubricant allows carbon deposits to stick and cause far more damage than if left dry, even in small amounts. While the result will not be catastrophic by any measure, your gun will last longer and was designed for a dry gas cylinder.
As for polishing it, there's really no point, if your guns cycles and feeds fine, why bother enlarging tolerances and messing with things?
If you clean your rifle throughly after shooting it shouldnt matter all that much.
Leave it alone !! Shooters experimented with these attempts to polish about 20 years ago and then they discovered extraction problems.
Guess Why ?
Leave the gas system DRY. If you really want to help the gas system out, leave a couple of drops of Shooter's Choice (fouling removal purposes) or USGI BORE cleaner on the piston. Then reassemble and shoot. This blows out the crud on the gas system interior.
Otherwise, please leave it alone !
If you really want to help things further and you just cannot help yourself, then add a dab of grease (any grease) on the gas plug threads on reassembling. This prevents any cross threading of those fine, fine metric threads. Also the grease prevents any chance of seizing after you defend your family from hundreds of attacking zombies. LOL
Cheers,
Barney
Guess Why ?
Leave the gas system DRY. If you really want to help the gas system out, leave a couple of drops of Shooter's Choice (fouling removal purposes) or USGI BORE cleaner on the piston. Then reassemble and shoot. This blows out the crud on the gas system interior.
Otherwise, please leave it alone !
If you really want to help things further and you just cannot help yourself, then add a dab of grease (any grease) on the gas plug threads on reassembling. This prevents any cross threading of those fine, fine metric threads. Also the grease prevents any chance of seizing after you defend your family from hundreds of attacking zombies. LOL
Cheers,
Barney
As has been said already, the M-14 Gas System should be run DRY!! Lubricants left in the gas assembly can diesel under compression, and this can cause erratic piston push = less accuracy.
Polishing the piston top might make cleanup a teensy bit easier. Much more critical would be cleaning out the carbon in the piston center. Polishing the piston sides can reduce diameter, increase blow by, and if way too small, decrease reliability. To test your piston/cylinder for fit, take the entire gas assembly off and get it perfectly clean, perfectly dry. Then, put the piston in the cylinder and with a finger covering the gas cyl gas port, hold the assembly vertical, and let the piston slide down. The SLOWER the piston drops out, the better the fit. The actual diameter of the piston is not as critical as the clearance between piston OD and cylinder ID.
PS: dropping the piston onto a concrete floor will absolutely, definitely, positively NOT increase accuracy.
PPS: WELDING up a unitised gas assembly will quite probably warp or distort the gas cylinder around the weld points, causing binding and erratic reliablity again ... which is why it is recommended to ream out the GI cylinders after a weld job. The Chinese cylinders and pistons , being chrome plated, have their own issues, but SOME Chinese pistons fit perfectly in SOME GI cylinders. The Chinese pistons are often a bit larger in diam, so can be used to tighten up a worn [ or reamed ] GI cylinder.
Polishing the piston top might make cleanup a teensy bit easier. Much more critical would be cleaning out the carbon in the piston center. Polishing the piston sides can reduce diameter, increase blow by, and if way too small, decrease reliability. To test your piston/cylinder for fit, take the entire gas assembly off and get it perfectly clean, perfectly dry. Then, put the piston in the cylinder and with a finger covering the gas cyl gas port, hold the assembly vertical, and let the piston slide down. The SLOWER the piston drops out, the better the fit. The actual diameter of the piston is not as critical as the clearance between piston OD and cylinder ID.
PS: dropping the piston onto a concrete floor will absolutely, definitely, positively NOT increase accuracy.
PPS: WELDING up a unitised gas assembly will quite probably warp or distort the gas cylinder around the weld points, causing binding and erratic reliablity again ... which is why it is recommended to ream out the GI cylinders after a weld job. The Chinese cylinders and pistons , being chrome plated, have their own issues, but SOME Chinese pistons fit perfectly in SOME GI cylinders. The Chinese pistons are often a bit larger in diam, so can be used to tighten up a worn [ or reamed ] GI cylinder.
