Im thinking of getting a 18inch SPR for something different. Should I go with a rifle gas system? Everything I have now uses the carbine system which I know is more violent and harder on the gun. Is there any difference between the carbine, mid and rifle systems besides the gas tubes?
I’d go 18" mid-length. A little more inherently reliable in cold climates. Mid-length works well on the Noveske 18" SPRs. If you’re going to shoot it suppressed a lot get the rifle length.
If you don’t live where it gets cold and you don’t shoot wolf ammo when there is snow on the ground, go rifle length gas system like a real SPR.
You could also go intermediate length which is between rifle and mid-length.
Rifle length it is, I never shoot Wolf except in AK’s and I live in the Phoenix, AZ area where it is as hot as the Devils us Gas System.
Thanks guys
Just for my information - why is rifle length better for surpressed fire, and mid length better for cold weather? I understand, generally the rifle/mid/carbine gas system differences and their effect on reliability, cycle rate, etc. outside of the weather and the surpressor, but am not aware what effect the surpressor and the weather introduce.
Just tryin’ to further my education … 
Thanks.
Adding a suppressor makes more gas go through the system and increases bolt velocity and cyclic rate. So using a rifle gas system would be increasing the size of the system. The bigger the gas system the lower bolt velocities and cyclic rate.
I actually recommend the mid-length for use with a suppressor.
Mid-length runs a smaller port size so the addition of a suppressor has LESS effect than on a rifle setup where the port is opened up more to account for the shorter dwell time.
For pure competetion, I recommend the rifle length setup for it’s smooth operation ans short dwell which helps you stay on target.
Cold weather reduces the operating pressure of the ammo and can also make the lubrication heavier (more sluggish movement).
Cold weather combined with a short dwell time has a potential for short stroking problems.
In reality it usually just causes a failure to lock back on an empty mag.
Function from shot-shot is usually fine.
While we’re all talking about mid-lengths: Is there any down side to running a 14.5" midlength ? I plan on shooting M193, Blue Box, and Wolf (for plinking). And here in NJ it does get cold.
HLD…
OK, that all makes sense. Thanks for the explanation.
Im one of those guys who can pull a trigger and thats about it. Does a middy use the its own gas tube? I have only seen rifle and carbine length tubes thats why I ask. If I were to get a midlength what additional parts are needed over a carbine? I like spares of almost everything:p
Yes it has a mid-length gas tube. The system is 2" longer than a CAR length system and 3" shorter than a rifle length system.
Same parts, but it’s the barrel which determines which system you have (or more accurately where it’s gas port is). Same gas tube roll pin, FSB (or gas block) and a mid-length sized gas tube.
Ditto.
C4
The image is easier to read on my gas systems page
Carbine to Middy
Middy to Rifle
an old link to an ARF album pic
Somewhere I had a pic of them stripped out besdie each other and refrencing a yard stick, but my old laptop died in California two weeks ago - and I have not got the data recovered before I went back to work.
Thanks for the pics and illustrations. Leave it to Randall to have a tutorial for about everything 
Its amazing the amount of information on this board. I have learned more on here in less than a year about the insides of the platform thn I did in 18years as a lowspeed guy in a hispeed unit with a target on my back.
When you have answered questions over and over for years like I have, you tend to make up tutorials and pictures to better explain things.
I keep a collection of technical photos here to help explain things.
Feel free to browse the folder.
Many of the pictures are either self-explanatory, or named in such a way as to explain what they are.
Please read the “read this first” text file at the top before you save or re-use any of the pictures.
Randall you are the man.