I shot my recently built Grendel today to function test it. It has a cut down 24" AR Stoner bbl and Bolt. It's a rifle length gas system with a Syrac adj gas block. I have a Magpul rifle stock and a Noveske 13.5 NSR holding it together.
Absolutely no function problems except the $100 dollar adj gas block seems to be letting some gas out the adjustment screw. I'll post pics shortly, but has anyone had this problem?
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I have never had an issue with the Syrac or the DA7 adjustable gas blocks. I had a friend with a JP adj gas block that failed him but I hear other people have had good luck with them. How far out did you have to adjust the screw? I noticed when I adjusted the Syrac I only had to turn it one half turn to get the appropriate gas with most of my rifles. I am interested in seeing your pictures. I just shot one of my rifles 2 hours ago and I have no gas residue at all.
I may have screwed the adjustment screw out too far!!! Damm, I re-read the instructions and it said 4 turns out max. The screw did not come out of the block, but it's definitely blowing gas out the screw or the push button.
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Nukes Wrote:In what way did your friend's JP fail?
His adjustment screw fell out during a multi gun match after he experienced a few malfunctions to cycle. The manufacturer replaced the screw and it seems to be running top notch so far .
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04-27-2013, 01:54 AM
(This post was last modified: 04-27-2013, 01:57 AM by cbe1962.)
If the push button still holds the adjustment screw from turning, I don't think you brought the screw out too far. The reason they say that, is the internal parts are held in place by the adjustment screw, take it out and those parts fall out. If they fall out the push button won't lock the adjustment screw in place any more.
I have a Syrac too and have seen evidence of a small amount of leakage. This is my first adj gas block and I just assumed given the pressures, that some leakage was normal. I will be interested to hear what others say.
I am with Montana - 1/2 to 3/4 turn from closed was enough for mine to function properly.