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12/30/2010 2:30:40 PM EDT
How many people run middy piston systems?  If you do, any problems?

Does the longer operating rod cause more or less stress on the system?  

It seems like having a longer rod on a short stroke system, would put more stress on the rod itself.  I am also assuming the pressure curve is similar to a carbine system, but honestly I do not know.  

Does anyone have any information specifically on middy systems?
12/30/2010 2:51:49 PM EDT
[#1]
The mid-gas system lets the chamber pressure drop before trying to jerk the case out of the chamber, it puts less stress on the bolt lugs, cam pin , cam pin area of the bolt and the cam pin slot in the carrier.
Pressure on the OP rod is less with a mid gas system.
12/30/2010 3:09:46 PM EDT
[#2]
OP, I would say it's about a wash. You get lower pressures at the gas port with a mid-length system and a milder cycling impulse. In a mid-length, the op-rod is longer and more easily bent due to its extra length, but this issue is probably negated by its milder impulse. Conversely, a carbine length system has higher gas port pressures and a more forceful cycling impulse. The op-rod in the carbine is shorter and theoretically should be able to handle the higher pressures without flex. You just get rougher cycling with a carbine.

I would go with the mid-length simply for the benefit of smoother cycling and less jolt overall.
12/30/2010 7:14:26 PM EDT
[#3]
Interesting.  Thank you for the information guys.

Looks like I am going with a midlegth system.
12/31/2010 10:28:41 AM EDT
[#4]
LMT mid piston next to DI 14.5s in 5.56 and 6.8



12/31/2010 4:05:10 PM EDT
[#5]
I have mid length and rifle length Adams kits. They both run like sewing machines.

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