What is the advantage of a mid length gas system over a carbine length gas system, or is there any? Just curious, and is there also an advantage of using a full/rifle length gas system over that of a mid length or carbine? Tanx.

BTW I did a search and nothing.

Generally the longer the gas system the lower the gas pressure in the system. This lower pressure generally results in increased reliability and less wear and tear.

Shooting one is kind of like having the recoil of a rifle with the length of a carbine. I think it's the best of both worlds. If I could only own one AR it would be a midlength.

This, plus it provides a longer site radius if using irons, more room on the handguard to grab and the ability to grab farther up, and if you go with a railed setup more room for accessories.  Also, some claim slightly less recoil from that of a carbine but I personally can't tell a difference.

This.  My lighter middy has much less recoil than my friends heavier HBAR 16" carbine.  There is no advantage: weight, length, or performance to a 16" carbine over a 16" middy.  I dont know why they even bother making them.

The advantages of the midlength gas system over carbine are that from both human and mechanical engineering the midlength is a more optimal configuration for a 14.5 - 16 inch barrel length. With a direct gas system like the AR has, matching the gas system length to the overall barrel length is critical to optimum operation of the firearm.

Human: Longer sight radius, more handguard length, smoother operation.

Mechanical: relationship of pressure to dwell time much closer to optimum than carbine length gas system, so less wear, higher reliability, reduced stress on components, reduced gas port erosion.

Dupes by the dozen...
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