04-21-2022, 12:43 PM
BluntForceTrauma Wrote:When I get around to stocking 18" 6mmARC barrels, they'll have a RLGS like my 18" Grendels (when I get around to restocking them). In production now are 6ARC 16" and 20" and 65G 14.5".
Having said that, I don't think the 6ARC using CFE223 or LeveRevolution powder needs a non-standard gas tube length any more than 65G using those powders. And having said THAT, barrels longer than 20" in 556 and 65G and 6ARC probably should have always had RLGS + X. I don't know that from experience, just remember Bill Alexander hinting at that.
Yesterday was out function-testing my 6ARC 12" barrel and its CLGS ejected beautifully. THEORETICALLY, gas port locations can be tweaked as much as gas port hole diameters, and you could end up with a million different gas tube lengths. However, if the intention is to keep things simple and use standard tubes, the key is properly sizing the gas port and it works perfectly well in PRACTICE.
Gas port sizing matters, but it doesn't change when the flow into the gas system begins or ends, gas system length and distance between the port and the end of the barrel determines that. That's why it's not surprising that a carbine length gas system works well on a 12" barrel ARC, I don't think carbine would be great for an 18"-20" barrel, nor would a pistol length system be as good for your 12" barrel, regardless of port size. And of course, putting a can on the end increases the length, if not magnitude of the positive pressure pulse on the gas system, making things worse.
Rifle length would be fine with me on an 18" ARC, and rifle length is the standard for accuracy focused 18" .223 ARs, it's the mid-length system that WC opted for here that is the anomaly. Rifle+1 would also be fine with me, I'm pretty confident that Proof did their homework when working with Hornady on the development, and of course, it's not like +1 systems are terribly rare either.
I might wind up picking up one of your 18" barrels, and probably already would have if they were available. When I had emailed a while ago it didn't sound like you were going to get to them before late summer or fall, so of course I have my eye out for other options that come up before then. I already have a 21" ARC, 16" Grendel and really feel 18" is the sweet spot for ARC, so unfortunately I'm not really interested in the 16" and 20" in the current batch.