Direct Impingement vs Piston Driven

[going_home]

Your preference ?

Reasons ?

[vintage]

no preference really. If you had a bump stock and wanted to make a light mg than probably piston driven for a little more weight to the mechanism.

[Nobody]

Actually the AR15 is not a true direct impingement system, as the bolt head acts as the piston. So your question is moot.

Have a nice day

[Loguzzzzzz]

Actually the AR15 is not a true direct impingement system, as the bolt head acts as the piston. So your question is moot.

Have a nice day

Your response it moot and once again non poingnant. . .

[Loguzzzzzz]

Piston driven is cleaner.
If you make cleaning the front part of your normal cleanup regimen then "direct impingement" will not be a problem.

[Olsson]

Is the original question meant to actually mean Direct Impingement, or is it meant to refer to the AR15/M16 type of gas operation? Which, as has been mentioned, is somewhat of a hybrid.

Regarding the AR15/M16 mechanic, my personal opinion is that the M16 family of firearms is the best firearm there is, no competition, until you have to actually fire it. Well, at least if you have to fire it, expecting someone to fire at you in return. I would rather have the extra weight of a piston, than risking my firearm to seize up in the middle of a firefight. I'm speaking from first hand experience of both, and even though my load out was way in excess of a 100 lbs, I still prefer a piston driven assault rifle.

[Army]

Actually the AR15 is not a true direct impingement system, as the bolt head acts as the piston. So your question is moot.

Have a nice day

No. The bolt face/head does not seal nor vent (before you ask, the cartridge case seals the chamber). The gas directly impinges (hence the moniker) on the bolt shaft, the gas rings seal the pressure from leaking forward and keep the bolt forward in battery. While the gas pressure forces the carrier to the rear (equal and opposite reaction), the carrier causes the bolt key to ride it's groove, rotating the bolt out of battery, and follow the carrier mass to the rear after all excess gas pressure has left the system.

At the time of invention, Stoner didn't want the added problems of more parts that consisted a piston system (which was already in wide use in a large variety of weapon systems). The added weight would also discount the purpose and goal of an ultralight rifle.

The main problem with piston systems, is nothing is keeping the bolt in battery during the firing sequence, outside of back-pressure thrust. Once the carrier begins to move, the bolt is free floating. This, is not a good thing.