AR Gas/DI explanation

My question is why weren't they made w pistons in the first place
Click to expand...

Unnecessary for the gun to function reliably
More parts to break
Added weight (Yes, there IS SOME)
Increased complexity in general over simply having a pipe direct the gas all the way back.
 
My AR is a "dirty DI" and.... I would trust my life to it.

However, the piston thing is not just a gimmick, it does have merit. Along with cost and weight. I understand why they exist and why people like them.
 
I guess I will need to do some weight training because I own a heavier piston rifle...just weighed my piston rod and end cap...came in at a whopping 3.46 ounces.

After about 2000 rounds there are no signs of "Carrier Tilt" anywhere in the buffer tube or the bolt carrier of my S&W M&P15.

This discussion will always generate humorous comments, mostly from people who have no direct knowledge, or who have never handled, shot or cleaned a piston AR. It will be interesting to see which way the Military goes when issuing new contracts for weapon systems in the future.

Meanwhile I need to go lift some weights...........:D
 
Last edited:
"Why weren't they designed with pistons in the first place?"

Ask Eugene Stoner. He is no longer with us, but his rifle design is his legacy.

As for the comments about the weight,

1) I'm not doubting anyone's ability to lift a rifle

2) One cannot add parts to something and expect it to be lighter than it was

That is all.
 
If you're worried about mass more than weight, you should be worrying about where the oxygen is coming from to make the gun go boom.
 
RT, neither of you links prove anything one way or another. In the first video, the gun would have performed just as well either way Piston or DI. Dirt, mud and water are not the factors that make any difference between the two, if there is any difference.
The damage in the second link could have been caused by any number of problems, loose carrier key for one or even a worn pivot pin. I have and use both gas piston and DI and haven't formed any definite opinions yet but, just because someone posted a picture of a problem with his gun on a shooting forum and claims it was caused by carrier tilt due to a gas piston kit doesn't make if fact.
 
Yeah, Still what does that article have to do with carrier tilt or Gas Piston vs DI?
I will say that I only have experience with the Osprey Defense system, since it is the one that I own but, with the way it is designed I don't see where there is any chance of carrier tilt. It basically boils down to either forcing the BCG back with hot gas, or forcing it back with a steel rod. Why would one cause it to tilt more than the other. The steel rod is guided through the reciever by a steel bushing that is only slightly larger than the rod, just enough so that it will move back and forth and will not let it tilt or wobble or anything else. It pushes straight back so where does the tilt come in?
 
Good thread, this has answered some of my questions about the difference between the 2.

If you are just starting on the AR platform, DI will work just fine and is actually better to start with. I'm in this same position with only my 2nd M4 and parts are very easy to swap/build. As you progress and learn, you can look into spending a little extran on the piston system.
 
Another cool thing about piston AR's:

IF you and your family are sound asleep, a piston AR will load and charge and aim @ the perp, recite the miranda rights, and put the bad guy to sleep. That's just the beginning... it will also wash a load of dishes and laundry, because it's THAT clean!!!
 
Me, too. I bought a coated bolt carrier group, so I just have to wipe it down, and scrape the carbon off the tail.

IMAG0063.jpg
 
You must log in or register to reply here.
Back
Top