Gas Cylinder Tilt Test ?
- Thread starter Chris S
- Start date
I'm new to this, but I believe the Chinese cylinders are slightly larger than USGI spec, which would cause the problem your describing, if the cylinders you are trying are Chinese manf. Like I said I'm just going on memory from what I've read.
My original Norinco piston would bind half way, had to pull on it to get it all the way. Honed it down on a lathe with fine sharpening stone to get rid of the high spots, worked OK but ordered the Sadlack tin as I was not impressed with the Norinco quality. Let you know if it works better when it comes in.
Like FYN said the pistons are not the same ! I miced the the tin one and the norc one , and they are not the same. You will find that the the sadlak is smaller ! I still cant get one of my cylinders to work with any of the pistons,i guess it is worn out .
What to do, what to do
Brownells has SAI bare gas cylinders for under 60.00 USD.
You'll also need an M1A gas plug, and spindle kit. They also have the gas band plate.
Overall, VERY affordable even if it must be split into 2 orders to stay under the 100 limit.
Then your sadlak or other US made piston will work as designed.
Chinese gas cylinders and pistons do not share the same dimensions for internal function/dimension and gas volume, when compared to their USGI or other US counter parts.
Close enough to work, but not compatable internally
Brownells has SAI bare gas cylinders for under 60.00 USD.
You'll also need an M1A gas plug, and spindle kit. They also have the gas band plate.
Overall, VERY affordable even if it must be split into 2 orders to stay under the 100 limit.
Then your sadlak or other US made piston will work as designed.
Chinese gas cylinders and pistons do not share the same dimensions for internal function/dimension and gas volume, when compared to their USGI or other US counter parts.
Close enough to work, but not compatable internally
Yet another Chinese Norinco quierk? Should work to USGI-Mil specs for any M14-305. And stupid me, I thought they reverse engineered those guns according to USGI-Mil spec. Not impressed! Hope the Sadlak piston I ordered works without numerous other parts as suggested by M14 doc
What exactly does close enough to work, but not compatible internally mean? Will it work ok or not?. Not looking for match grade performance just something that works and provides good groups! Sheech every time I buy something, someone tells me to get something else to make it work. What ever happened to the keep it simple rule?
Close enough to work means that the chinese copied the parts close enough that the rifle functions with similar loads as called for in the design. BUT the parts are different enough that US made cylinders and pistons are generally NOT compatable with chinese cylinders and pistons
US piston = undersize in chinese cylinder
Chinese piston = oversize for US spec cylinder
There have been rare occasions where I've seen the sadlak non grooved piston function in a chinese cylinder, but generally no.
US piston = undersize in chinese cylinder
Chinese piston = oversize for US spec cylinder
There have been rare occasions where I've seen the sadlak non grooved piston function in a chinese cylinder, but generally no.
Got it TX. Guess I have a Sadlak NM tin for sale now? Lot's of folks looking for that and dont know about the conflict between parts. Just a wealth of information on here. You the Man Doc! Further questions, if I use the thing which is not the right size, will I loose any body parts besides my ####? (read alot on here about Dicks falling off
and some other parts of the gun either blowing up in your face or going down range several yards. Will it go into battery repeatadly with standard 308W commercial rounds say 168 gr. Hornady A-Max. So far, all I have done to the thing is change the oprod spring guide to a Sadlak NM and the spring to a chrome silicon with a spring recoil pad. Maybe these dont work or fit properly either because of Chinese mfg. specs????Before I spend any more $$$$ on this thing, lots of products out there, what the f..K fits this rifle?
p.s. cant even find a butt pad that fits the stock rifle because the after market products require a longer bottom bolt to fit the thing that is not available anywhere. Make your own? Ya right, I have time and tools for that?
Best regards...........................
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I've wondered this myself but never followed up. I have a whole bunch of chinese cylinders that will not function with any piston I have tried. Some of these have seen several thousand rounds and are simply past their service life, but others are from newish rifles that short stroked from day one.
A loose piston , either from wear or simply undersize or a worn out gas cylinder, will make the rifle short stroke. Ie: fail to feed and fire from the magazine after the initial shot or during a volley.
If your rifle shoots and functions normally, the piston/cylinder combo is functioning as per design
Using the sadlak piston may or may not work. Like the doc said it can cause short stroking issues but it's not going to cause your d*ck to implode. Try it. I bought the same piston thinking the same as you, and since I'm currently a lazy bastard I havnt bothered swapping it back. It's been a couple hundred rounds so far, and my d*ck is still swinging. Swapping out the gas cylinder as suggested by the doc will be probably the best fix, but give it a go, spend more money later if you don't want to now.
Guys ask me all the time what accessorries I recommend for improving accuracy. Save your money by first establishing your rifles base line accuracy.
-A tightening of the rifle's parts to make up for sloppy chinese assembly.
- Stock fit, improved with bedding or replace with a quality aftermarket that suits your taste.
- NM oprod spring guide rod
- Unitizing gas system
- correct trigger job
Once these things are done
- improved sights or mount and optic ( here I recommend steel mounts for standard scopes)
- then it's load developement.
When the parts on my chinese rifles won't work or havepast their service life, I source compatable US spec items.... Mainly because there is no source to just go buy chinese replacement parts.
Some guys opt to just replace things like gas systems and oprods and sights right off the bat.
A guy can save himself all kinds of money and the drawer full of bits that did not work or did nothing to improve the rifle, by following the steps above to establish your rifles base accuracy.
-A tightening of the rifle's parts to make up for sloppy chinese assembly.
- Stock fit, improved with bedding or replace with a quality aftermarket that suits your taste.
- NM oprod spring guide rod
- Unitizing gas system
- correct trigger job
Once these things are done
- improved sights or mount and optic ( here I recommend steel mounts for standard scopes)
- then it's load developement.
When the parts on my chinese rifles won't work or havepast their service life, I source compatable US spec items.... Mainly because there is no source to just go buy chinese replacement parts.
Some guys opt to just replace things like gas systems and oprods and sights right off the bat.
A guy can save himself all kinds of money and the drawer full of bits that did not work or did nothing to improve the rifle, by following the steps above to establish your rifles base accuracy.
Norinco M14-305s review
A loose piston , either from wear or simply undersize or a worn out gas cylinder, will make the rifle short stroke. Ie: fail to feed and fire from the magazine after the initial shot or during a volley.
If your rifle shoots and functions normally, the piston/cylinder combo is functioning as per design[/QUOTE]
Ya, as per design?, who the heck designed this Chinese want to be? Will try it at my own risk again with after market parts and hope my #### dont fall off. NOT what I was looking for. Was looking to get something more compatible to a M14 with interchangeable parts without the cost. Guess what, mine is a piece of S..t. and good luck finding parts that fit.
Without spending more than twice the $$$ on this for all the bells and whistles to make it work and look right, you may want to consider your purchase options. After market parts, forget about it, alot dont fit! Unitizing, glassing, new USGI bolts&parts, custom stocks, barrels, scope mount etc,etc,etc. Unless you have a budget of $2000+ this is NOT the gun for you, and you can do better with that kind of $$$$
Just shoot the thing out of the box, if it's not up to your expectations and does not meet your expectations, sell the puppy, dont waste any more $ and get a good rifle. You can save alot of $ and Agrevation with a good Lee Enfield 303 or maybe a good old Springfield M14, but I also have certain reservations with that one.......
A loose piston , either from wear or simply undersize or a worn out gas cylinder, will make the rifle short stroke. Ie: fail to feed and fire from the magazine after the initial shot or during a volley.
If your rifle shoots and functions normally, the piston/cylinder combo is functioning as per design[/QUOTE]
Ya, as per design?, who the heck designed this Chinese want to be? Will try it at my own risk again with after market parts and hope my #### dont fall off. NOT what I was looking for. Was looking to get something more compatible to a M14 with interchangeable parts without the cost. Guess what, mine is a piece of S..t. and good luck finding parts that fit.
Without spending more than twice the $$$ on this for all the bells and whistles to make it work and look right, you may want to consider your purchase options. After market parts, forget about it, alot dont fit! Unitizing, glassing, new USGI bolts&parts, custom stocks, barrels, scope mount etc,etc,etc. Unless you have a budget of $2000+ this is NOT the gun for you, and you can do better with that kind of $$$$
Just shoot the thing out of the box, if it's not up to your expectations and does not meet your expectations, sell the puppy, dont waste any more $ and get a good rifle. You can save alot of $ and Agrevation with a good Lee Enfield 303 or maybe a good old Springfield M14, but I also have certain reservations with that one.......
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