About to order another adjustable gas block for my next build and I’m really liking what I see from Syrac. However, I am a little hesitant about the Gen 2 with it’s spring-loaded detent vs the Gen 1 where you have to depress the spring-loaded button with another tool. I’m worried about things like recoil, eventual wear, carbon buildup, etc… eventually interfering with that and causing it to go loose so that the set screw can just turn freely.
I attempted to look around for some reliability reports or some explanation on the design and could’t find much.
Does anyone have any explanation of the reliability of the Gen II? Is it pretty proven that it’s a guaranteed improvement and pretty much impossible to go south? Or is everyone still feeling like for ultimate reliability the Gen 1 is still the way to go?
Yikes. That’s what I was afraid of. When it did seize, did it seize in the set position, so you just couldn’t adjust it any longer? That’d probably be fine with me as I don’t ever plan on adjusting it after I get it setup. But if it seized so that the set screw could turn freely that worries me.
I believe F2S does light coats of fireclean to his suppressor mounts to make removal of the suppressor easier with carbon build up. Might be an option to combat the seizing issue on the internal detent via carbon build up.
The carbon got into the threads as well as the detent, so the screw was stuck in the position I set it originally. Once the carbon broke loose, the screw would turn, but it would not click at each position. The screw was not loose enough to move under recoil.
If you know how the Syrac’s work, the detent rides up the corner between each flat on the screw. When the carbon built up, the detent got stuck in the “up” position preventing each position from clicking. I’m not sure if this was an isolated incident, but it only had around 500 rounds at the time.
I used Fireclean on the detent and have yet to have any more problems. I would advise to do the same if you have a needle point lube bottle. I went in through the port inside of the GB.
I Frog Lubed my Syrac but and that didn’t happen but it does vent the restricted over pressure out through the detention/spring hole…that tends to hit your hand if your using an open rail like a KMR. Check out the SLR.
The SLR vents out the opposite side, to the front of the leaf spring. If left unattended with slim rails like the NSR or KMR, the carbon build up can form a bridge to the interior of the rail itself and affectively make the barrel assembly no longer free floating.
I’d imagine the Syrac is capable of the same.
All adjustable blocks will seize or “carbon weld” over time.
What I’ve found with the SLR is the meter screw gets welded but the leaf spring and detent can still be easily removed. The Syrac design… not so much.
SLR states specifically that their block vents forward and was designed this way so as to keep the carbon and blowback off either support hand. It is well established that most blocks will carbon lock the screw over time. The solution is to regularly give them an adjustment turn to break that build up loose. You are correct about the Syrac, once welded you haver I punch the pin and pull everything out to clean it.
I don’t care what SLR states. I have over 2,500 suppressed rounds through a Sentry 7 here and have had to remove carbon build up from where the leaf spring leaks numerous times; it never self seals. I have since sealed it through my own means and haven’t had an issue. I even tested if it was leaking at the front edge of the leaf spring by placing a good amount of RTV silicone in and over the gap. The first few shots blew out the silicone so there’s a decent amount of pressure there. I’ve also tried numerous leaf springs to see if it was a manufacturing abnormality.
Giving it a “regular adjustment” after as little as 500 rounds of suppressed fire is a significant pain in the ass and since the host gun is dedicated suppressed, it can stay where it is. I consider these blocks “set and forget”.
All these detent adjustable blocks are great but they do leak and due to the gap size and gas pressure where the leak is… I haven’t seen one seal itself yet.
Ok then. Would you mind sharing your “my own means” sealing method for the benefit of all here?
To your last point, that restricted gas has to go somewhere so there’s not going to be a block that is “leak free”. You can restrict that gas from going into the action but it has to be vented somewhere.
My experience as well. Luckily I’ve got a RIS II to catch most of it. Lol. That won’t be the case on the wife’s gun because it’s going to be a KMR so I’m looking for something a bit “cleaner”.
If gas leakage from an adjustable block bothers you, consider using an adjustable carrier key instead. Adjustable carrier keys are available from Rubber City Armory or Sun Devil Manufacturing . The additional advantage is that a regular gas block can be used (pinned if you prefer), and this in turn makes it easy to switch to a non-adjustable carrier whenever you wish.