20 practical p-dog setup gas system length...?

deaddogs

Private
Minuteman
Mar 8, 2012
92
32
39
Lacrosse Wisconsin
So I’m putting together a 20 prac for a prairie dog rig. I’m planning on going for a heavy bench queen type setup. Here’s my parts list I have so far.
Aero enhanced upper or dpms lo- pro (can’t decide)
Superlative gas block
Mullerworks 11 twist finished at 24-26, .936 gas block and 920 at muzzle..?
My hang up here is the gas length, I don’t know if there is any benefit in a small caliber plus gas system (+1,+2,+3) ..? Any help this type of setup is appreciated. Thanks!
 

supercorndogs

Ham Fisted Gorilla
Minuteman
Feb 17, 2014
7,608
7,321
Colorado
Ask the place making it. There is a lot of space between a rifle length gas port and the muzzle end of a 26" barrel, but those little bullets are going fast. I did an 18" with rifle length gas, and it doesn't like to run without a suppressor. I think it is because of such short dwell time.
 

deaddogs

Private
Minuteman
Mar 8, 2012
92
32
39
Lacrosse Wisconsin
Well, my smith is a benchrest guy and hasn’t built many ar barrels, so we are working on this together. He will be doing the machine work and I need to do the r&d work. I can’t believe there would be any downfall to a longer gas system. Longer bolt lock-up time
Easier on brass.. not sure if the port size will need to a bit oversized.
just curious if anyone has any experience with these long barreled small bores
 

ScarlettRed

Private
Minuteman
Aug 7, 2017
184
101
Colorado
I've got a 22" 20 tactical with a rifle length tube. I shoot with a suppressor and a bootleg adjustable carrier and have the gas turned on full to operate. Makes no sense, but that's what works. 1-10 twist, 39g sierra bk. Smokes dogs though.
 

chutinlead

Chutin Big Lead
Minuteman
Apr 10, 2018
438
171
Wyoming
Mine is a 20" barrel with a rifle length gas system, adjustable gas block, homemade JP Silent Capture Spring Copy and I have the gas turned way down. It is such a slow smooth recoil that I've had friends wonder if it went off.
 

Halfnutz

Sergeant
Supporter
Minuteman
  • Jan 14, 2008
    1,211
    699
    Peoria County, Illinois
    My WOA is 24" with rifle length gas tube.
    FWIW I run WOA gas block and an H2 buffer.
    I use lower with multiple uppers, the H2 buffer works in all so far so I've never changed it.
    Great cartridge and a lot of fun.
     

    deaddogs

    Private
    Minuteman
    Mar 8, 2012
    92
    32
    39
    Lacrosse Wisconsin
    I spoke with Paul Craddock today and he helped me out tremendously. He recommended a +1 gas on a 24 inch tube, and answered all other questions I had. What a great gentleman! Great to talk to, wealth of knowledge. Only thing was he didn’t have a 11 twist tube in stock which I wanted..lol.
    Definitely would recommend craddock precision
     

    Bigtrucknut

    Private
    Minuteman
    Dec 9, 2020
    29
    15
    NoVA
    I shoot a DPMS in 243 Win with an AP M5E upper and BCG, 24" barrel (1:8 twist), rifle-length gas system, SLR adjustable gas block, and Armalite 3-port 308 muzzle brake. The rifle recoil is tuned with the adjustable gas block and replacement tungsten buffer weights in the rifle-length buffer (8.85 oz). Shoots like a dream, is extremely reliable, has no feeding or ejection issues, and the light, controlled recoil keeps me on target for quick follow-up shots. I've thought about going to a rifle length+2 gas system when I replace the barrel but this component mix works so well that I probably won't change it.
     

    Yondering

    Sergeant
    Minuteman
    Mar 16, 2017
    1,145
    715
    Skagit Valley, WA
    I built my 24" 20 Tac with a rifle length gas system; runs great. I'm sure you could also use a +1 or +2 system if you want; honestly I doubt you'd eve know the difference as long as the gas is tuned correctly (either through port sizing or gas block adjustment, doesn't matter).