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I have a 20" Monster barrel with a Superlative Arms gas block. Is it normal for a little gas to leak by where the gas tube comes out? It's not a large amount, a thin line at about 2 o'clock from the rear POV, and maybe a 1/4" long.
My only experience is with 300BLK pistols and I don't think they generate anywhere near the pressure this does (even with the supers) so it's not really a fair comparison. That and the barrels and gas blocks are both black but even rubbing a finger on them doesn't catch any gas residue. I had some gas issues after I first built the 6ARC and double checked alignment and pin, all seems to be centered and lined up right. Is this a normal thing to have some leakage? I have been running unsuppressed in restricted mode rather than blowby/bypass mode. Would bypassing help with the leakage at the gas tube-gas block interface?
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Not a problem if it is only a little, you might even get a little blow by around the journal of the gas block around the barrel. It may even seal itself up after a little carbon build up.
Are you having any issues with it cycling?
If you can not see the tyranny of having a gun ban enforced by men with guns... Then you fail to understand why the second amendment was written in the first place.
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I was having trouble with feeding and reliably going fully into battery. I have not got back to the range recently since then. When I took things apart to check alignment I found that, it is indeed a small amount. I had a carbine tube and buffer at the time and reluctantly bought a few others if I can't get what I need with tuning from the block, especially since I have a can. The AGB is somewhat new to me and figured I need to learn how to tune it whether suppressed or not.
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I don't know how many rounds you have through it, but it may take a couple hundred rounds to get things loosened up and worn in.
You need to adjust the gas block wide open and start closing it off until it does not cycle. then open it up 1/4 to 1/2 turn. You need to get it to cycle without the can first before you put the can back on.
If you are going to run it with out the can at times you need to get it running without it first.
If you can not see the tyranny of having a gun ban enforced by men with guns... Then you fail to understand why the second amendment was written in the first place.
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I appreciate your help and that was my thought too regarding tuning before the can. The rifle only has 40, mostly painfully single-fed rounds through it. Hopefully things will come together a little better as time goes by...kind of what I was hoping and it's reassuring coming from you .
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Couple other things to note. 1. Is the gas block/tube centered up in alignment, sometimes the fail to go totally into battery can be from the carrier knocking against the tube even slightly.
2.A carbine buffer means you have one of the shorter barrels? That and the suppressor make for higher pressures at the gb so getting a little leakage would be common. Plus what Dino said.
All the moving pieces need to cycle back and forth together to wear into each other, this could take 100 rounds in my experience.
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Does your bolt lock open on an empty mag? You could be over gassed - i.e., your bolt is moving too fast to allow a round to pop up before it returns to battery. All that excess pressure could also explain the leakage. Turning the gas down is the obvious solution.
#FJB
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You have an SA gas block so wide open is actually the middle position. Start there with a std spring and Buffer. If your mags are working good and I suggest a cpd 10rnd Grendel mag, the rifle should run with a little gas tuning. Load 1 round fire and see if it locks back. If not you are likely undergassed. If it locks back. Close gas a few clicks and repeat until your happy.
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I managed to get it exactly as you just said. I have ASC mags, grendel and ARC, that worked flawlessly. My only malfunctions were from reloads. Apparently my measurements were off a couple thousandths and the converted grendel brass didn't want to go into battery fully. I actually have reliable operation now a few clicks into bypass now.
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Sounds like you got her dialed in. Good news. Handloads can be finicky in some rifles that’s for sure. The SA has block is a good one and should fix any issues there. I run them on my Valkyries and they work well. I would say get a case gage but I haven’t scored one my self.
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I use the Hornady comparators and they work good, I just got confused on the fireformed dimensions, converted dimensions and unfired Hornady brass dimensions.....most importantly I didn't bump the shoulder back enough and was 0.003"+ longer than fireformed factory brass on my converted handloads (lesson learned). I got the rifle and dies dialed in now. Much more fun and engaging than mass loading 9mm.
