PDA

View Full Version : Technical: Why is there a threaded hole in my piston?


sturmgrenadiere
October 10, 2000, 23:59
The gas piston I got with my STG kit has a threaded hole on the face that contacts the bolt? I don't remember if my previous FAL had this, but I am curious why?

thorlin
October 11, 2000, 00:13
I honestly don't know...but as an engineer, I might suggest that if I were designing a part which was intended to spend it's useful life impacting or pushing against another part, I might consider building the piston rod short, then screwing in a hardened or sacrificial stub that would be easily replaced, and for which you might easily carry many spares. Sort of along the lines of steel threaded inserts in an aluminum part...

In this way, if I wanted to protect the carrier for some reason, I could use a softer stub, and if I wanted to make the piston rod softer and more resilient, I could use a very hard stub.

I have thought a lot about the contact between the piston and carrier...surprised that each surface showed so little damage on the R1 and STG/R1 kit's I have on hand.

Just speculation. I really have no idea.


Originally posted by sturmgrenadiere:
The gas piston I got with my STG kit has a threaded hole on the face that contacts the bolt? I don't remember if my previous FAL had this, but I am curious why?



------------------
Mike Thorlin
Peoria, AZ
STG/R1 - In-process
R1A1 - In-process
R1/Blg BBL - on the way...
"Life's tough, ... it's tougher when you're stupid." John Wayne, "Sands of Iwo Jima"

kev
October 11, 2000, 00:30
It's for the attachment of a cleaning accessory, whether bore or chamber brush I'm not sure. Might even be for a brush for the gas tube. Kinda fitting, what?

thorlin
October 11, 2000, 02:03
That's a very good idea....

And isn't the gas tube susceptible to carbon fouling?? Good idea.

Destructo6
October 11, 2000, 12:43
It threads onto the pull-through cleaning cord and the associated brushes. I've used it, as suggested above, to clean the gas tube as well as the chamber.

DSA sells the cleaning kit that is used with the gas piston's threads. It comes in a case that is about the same size as a magazine, making it easy to carry in a magpouch.