It's official, midlength gas systems are superior to carbine gas systems.
- Thread starter AB_blaster
- Start date
Pistol and Carbine gas systems are much harder on the barrel, and BCG. Much higher pressures than rifle and mid length systems. The time to unlock the bolt from the barrel is shorter, which puts more stress on the lugs for example.
Harder to tune well, too, and fussier about everything being just so in order to function 100%.
Mark
I have been eagerly awaiting the results of this test for some time now. The forum debates will now be settled. 14.5" mid is greater than 14.5" Carbine
This test isn't about whether midlength is superior to carbine gas, nor is it about 16" or greater barrels. It is about which is superior WITH A BARREL LENGTH OF 14.5". Mid length has come out on top.
I suspect we will start to see a trend of a lot more 14.5" midlength's hit the market. Especially since SOCOM will be adopting a mid 14.5 URG now that their testing is complete
This test isn't about whether midlength is superior to carbine gas, nor is it about 16" or greater barrels. It is about which is superior WITH A BARREL LENGTH OF 14.5". Mid length has come out on top.
I suspect we will start to see a trend of a lot more 14.5" midlength's hit the market. Especially since SOCOM will be adopting a mid 14.5 URG now that their testing is complete
The test mentions that the cold hammer forged barrels stay accurate longer than the standard M4A1 barrels, but they seem to be attributing that to the gas system? Seems pretty evident a CHF barrel is going to last longer than a GI barrel.
One note: there is nothing wrong with carbine systems. For a civilian shooter you are likely never going to "wear out" your carbine. A balanced carbine is reliable and proven to work. You can have some fun with it tuning it with buffer weights, muzzle breaks and stock choices. Mid lengths are great too, but 14.5 mid barrels still need to be tested with your preferred ammo, buffer weight etc.
How can a gas system affect barrel life in any way? The gas system engages after the bullet has long left the barrel!!!
just the fact that they mention barrel life invalidaded the whole article for me.
Gunnerlove
CGN Ultra frequent flyer
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Wasted time, money and effort.
You're right, a carbine gas system gun will run, but it's harder on parts with increased recoil and as tested appears to have more stoppages.
I think what they're getting at is gas port erosion and the surrounding rifling due to excessively high port pressures on the carbine gas.
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Mid-length is pretty good (and finally, a new improvement) but the carbine-length gas system has been around for over 50 years, just as long as the rifle-length gas system, and has always performed flawlessly and as intended in all sorts of automatic carbines in those 50 years. We're shooting semi-automatic carbines with magazine restrictions, so just think about that.
Just like Hilo71 said, there's nothing wrong with carbine-length gas systems but I would choose a mid-length system if given the choice just because it is indeed better for your carbine. I gladly build and use AR-15s with carbine-length gas systems to this day anyhow.
Just like Hilo71 said, there's nothing wrong with carbine-length gas systems but I would choose a mid-length system if given the choice just because it is indeed better for your carbine. I gladly build and use AR-15s with carbine-length gas systems to this day anyhow.
I haven't bought a carbine length for a long time. The last carbine length I built was on a DD FSB RIS2 so you can guess how long it was ago.
The reason carbine gas system exists, and also the reason carbines are 14.5", have to do with mounting bayonet on a XM177 gas system.
It has nothing to do with ballistics, reliability....etc. It is all because of the bayonet and part commonality.
Interesting enough, Mid Length exists because people wanted to mount bayonet on 16" civilian carbine. That's how Armalite under Mark Westrom came up with the idea to make the commercial market happy. People were obsessed with mounting bayonet back in the days. It was a forbidden fruit during the assault weapon ban. After the AWB sunset, no one seemed to care about the bayonet anymore.
Putting Mid length on a 14.5" carbine was probably first done by KAC ( which they have their own mid length), and then BCM made it popular following Armalite's length. The spot light on port pressure and extraction timing all came to life during SCAR time and all the talks about M4 PIP back in the 2000's, but the idea of Midlength's advantage could be traced to something called "pig tail" gas tube back in those days.
The reason carbine gas system exists, and also the reason carbines are 14.5", have to do with mounting bayonet on a XM177 gas system.
It has nothing to do with ballistics, reliability....etc. It is all because of the bayonet and part commonality.
Interesting enough, Mid Length exists because people wanted to mount bayonet on 16" civilian carbine. That's how Armalite under Mark Westrom came up with the idea to make the commercial market happy. People were obsessed with mounting bayonet back in the days. It was a forbidden fruit during the assault weapon ban. After the AWB sunset, no one seemed to care about the bayonet anymore.
Putting Mid length on a 14.5" carbine was probably first done by KAC ( which they have their own mid length), and then BCM made it popular following Armalite's length. The spot light on port pressure and extraction timing all came to life during SCAR time and all the talks about M4 PIP back in the 2000's, but the idea of Midlength's advantage could be traced to something called "pig tail" gas tube back in those days.
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Gas port erosion. Throat erosion. Higher gas PRESSURES in carbine systems places more STRESS on components, including the barrel and chamber.
