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Yes, thanks.

Its my understanding that almost all the Gen IIs are over gassed. I was having problems and damaged brass before the addition of the syrac ord. adjustable gas block. I really like the syrac gas block because it has a ball detent on the adjustent screw and is less likely to come out of adjustment. After a very simple adjustment I now have my DPMS gen II running like a top and brass is undamaged after firing. It still flings them out a few feet but not the half mile it used to.

I�m pretty impressed with my gen II. If they had uppers available for it I would build a second one in 6.5 creedmoor, or maybe a fast twist 243.

several on here mentioned the adjustable gas block to me on the Gen2 hunter, my concern was that on my gun the issue was ejector damage and not extractor damage. It put all the brass in a neat pile at about 3:30 or 4 but some of it was bad torn up with twin holes bored into the back of the case and a half moon bend between them.

This one shoots fine "out of the box" even with the crappy Ruger trigger. My first outing with it is below. The top hole in bottom target is before I cranked my elevation down shooting 150 BTSP's over varget, the second 3 shot group is WW 150 powerpoints. I have repeated this a few times now and the gun is consistent, these are not "best" hand picked groups. It sucks that it weights almost 11 pounds full up and 20 rounds.

The Ruger is definitey one of the more attractive options for .308's under $2,000. POF is another piston dirven .308 that is capable of very good accuracy around the $2K range. The one's I've shot would shoot MOA with match ammo. I wouldn't hesistate to use either one.

@Josh Sorrenson - An adjustable gas block will solve most cycle of operation issues on a large frame AR rifle. Having experimented with just about all of them, the Syrac Ordnance Gen II is the clear standout.

@jimmyp - Do you have Gen II DPMS that's damaging your brass? If this is the case, you'll want to install a heavier buffer.

I thought the same thing before I got the SLR.

Really... What feature or operational capability of the SLR puts it ahead of the Syrac?

My apologies, I noticed the Gen II part after I posted. My experience was with the Syrac Gen I which was a bit tedious to adjust and would freeze up as carbon built up. The clamp on version was also a bit big and would only fit under a few handguards. The Gen II may have resolved all those issues. If so, I am sure it ranks right up there with the SLR.

Is that recoil spring/buffer considered heavy, (for a buffer?)

I put an 18" barrel on my DPMS and tuning the new adjustable gas block has not been as successful as I thought it would be.

Jimmy;

Any negative reaction to the 16" barrel?

No, it is made to work with the JP lightweight bolt carrier group. What problems are you having with tuning the gas block?

I have an adjustable gas block made "in house" by precision firearms in WV.

Trying to find the sweet spot seems impossible. Cannot tune it so the brass does not slam the deflector and get that crease in it every time. I glued the velcro doodad like y'all suggested. Next step I guess is a heavy buffer and just slow it all down. Or swap gas block.

Whose gas block are you using? There are really only two gas blocks on the market that are nearly linear when it comes to metering gas. They are the Syrac and SLR.

These folks are real nice people; he made the gas block but I don't see it on his web-page:
http://www.precisionfirearms.com/43.html

I had a suspicion that it was something along the lines of what you are saying about being "nearly-linear"

I had an instinctive thought that metering the gas was not as simple as might be thought.

Just checked out the SLR website. VERY good prices on everything.

Thanks y'all; I had never heard of SLR before.

What makes these 2 gas blocks so much better than any of the other adjustable gas blocks on the market??? I am running a Wilson adjustable block and it has worked great.

http://shopwilsoncombat.com/Adjusta...-Straight-Gas-Tube/productinfo/TR-AGB-C/

No, it's loud but I wear pro ears gold when I shoot it.

They have locking detents so screws can't back out or loosen yet they adjust with just one wrench like the others.

The photo below shows three metering screws. Syrac Ordnance on the left, SLR in the middle and JP on the right.

The JP is just an off the shelf cup tip set screw. The threaded body of the screw simply can't meter gas as effectively. When tuning a JP style block, you start with screw closed and back it out until the rifle completes a cycle of operation. These style gas blocks are either on or off given a specific cartridge. Once you hit the adjustment sweet spot, moving the screw in or out changes nothing (non-linear). I have no idea what type of screw the Wilson variant uses but I wouldn't be surprised if it were the same as a JP.

The Syrac and SLR variants work better because they have a machined metering surface. The metering screw on these models are precise enough that you can walk the ejection pattern through about 90 degrees. I'm prefer the Syrac varaint over the SLR for a few reasons:

1. The Syrac screw is purpose built whereas the SLR screw is just a turned down set screw.

2. The Syrac screw has four metering detents compared to the SLR which has three. This allows for more precise metering.

3. I'm not fond of the SLR leaf spring retention for the detent ball. It may be subjective but it's more likely to fail than the Syrac.

[quote=jimmyp]....

.... I have repeated this a few times now and the gun is consistent, these are not "best" hand picked groups. It sucks that it weights almost 11 pounds full up and 20 rounds.


It's unloaded weight is reported to be 8.6 lbs. The DPMS G2 AP4 is a little over a pound lighter per manufacturer's specs.

I wonder how light you can expect to go for a loaded 308 AR.