Aha! The buffer and tube are this kit from Midway.

The description at the link mentions a weight of 3.04 ounces.

We tinkered a good bit with the gas block last weekend; it’s not open all the way. I believe there are 17 detents in its span; it’s somewhere in the middle. I’ll get the wrench and count in a moment.

Here is the instruction sheet from Superlative.

That could be it.

Standard is generally 3oz and H1 is 3.8 and yours falls inbetween. If you have one you could swap out that may fix it. If it doesn't you may have to tweak that gas block a little. FOr science, only change one thing at a time, LOL. I would swap buffers first, then take a look at your GB

Thank you. I’ll look in the box for another buffer.

Meanwhile, I missed your earlier question about firing ’til empty mag. Answer: no, I couldn’t empty a magazine (only 3 rounds loaded) without a stoppage.

Guests on the way this evening; I’ll try to get out tomorrow and get a few more rounds through it.

Thank you all again, for your continued help. Gotta get this thing dialed in!

- - - - -

I was wrong earlier: there are 48 clicks (detents) across the span of this adjustable gas block. Mine was set at “5 from closed.” (Recording that here for the crowd, as well as for my own notes.) Instructions say to start at position 18 (fully open, full pressure) and adjust from that point. Will work on that tomorrow.

All-righty, friends and neighbors. It’s been a good day.

Yesterday afternoon I moved the gas block to achieve the .025” gap between the block and the shoulder on the barrel, following the instructions from Superlative Arms and contrary to Rustpot’s advice on page 1.

I got some time at a friend’s place this afternoon, and started testing again.
First round? Bolt didn’t close. I dropped the mag, ejected that round, fed it directly into the chamber, and dropped the bolt again. It fired fine, and ejected the empty brass well.

But the bolt didn’t close on the next round.

So I removed the handguard again, and moved the gas block about an inch away from the shoulder. I had the bright idea that I’d measure from the shoulder to the hole in the barrel, and then measure the distance from the “rear” of the gas block to the hole (do we call that a gashole? ), and do my best to line them up. And then I realized I had no way of measuring to the hole in the gas block without removing the gas tube, and I didn’t have the tools for that with me. So I had to think some more.

And then I wondered… if we assume (yes, I know what that does for us) that the hole distance is correct, how in the world do we make sure the gas block is in the right position radially about the barrel? The best I could do “in the field” was to squint a little and try to make sure the flat on the bottom of the gas block was parallel to the flat surfaces on the low part of the upper (where it meets the lower). So I squinted a little and lined that up the best I could. Tightened up the bolts, and set about trying again. (Is there a tool for that?)

I had some Remington UMC in the range bag, so I put four of those into the mag. All fed and ejected well.

Then three rounds of some Ammo Incorporated stuff I found in the bag. All fed and ejected well.

One leftover round of Hornady 80891? Fed and ejected.

I switched then to the Hornady 80867. Three rounds, fed and ejected.

Put the suppressor back on. Three more 80867, fed and ejected. Then three more. Then three more, and seven more after that.

By the time I had run through those and adjusted the scope a little, the final shot was about a half-inch off the center of the one-inch dot. At this point, variation from target center is a vthoky problem, more than a gun problem, for sure.

For kicks, I took an old tire from the front of my mower with me, filled a 2-liter bottle with water, and placed that inside the tire. I tried to hit the bottle cap, but struck a litte low. Then I put a couple of rounds into the tire itself. It’s interesting how small the entry holes are, and how rough the exit hole is.

A few pics: all shots were taken at 50 yards. (The holes at the top right of the cardboard were early shots, not aiming particularly well, just to prove function and ejection direction.)




Oddly enough, the hole in the black spot was one of the first three “good” shots. I should have just kept doing whatever I did there, right?

The hole with the 5 next to it is the last shot. I had ajusted the scope the wrong direction after the 1s and 2s, which led to the 3s and 4s being further right.





I didn’t have another buffer to try, but it appears that may not be the issue right now.
Further, I didn’t tinker more with the gas block adjustment, given that the gun was feeding properly and ejecting empties in the right direction.

I’ve still got some work to do, but I’ll consider it a success for the day.

Tomorrow evening I’ll open up this lower, see how much “glitter” is in there, and do some more cleaning.

- - -

So. Back to the root of the problem… where’s that “it ain’t got no gas in it” clip? At this point, all I can figure is that I hadn’t gotten the hole in the barrel and the hole in the gas block lined up well enough when I first installed it. I think.

Thanks for the update.
Good to learn that you evidently solved the problem.

Thank you all for your help!

- - - - - -

quote:

(Is there a tool for that?)

Sure enough, there is!
https://gasblockgenie.com/gas-block-genie-750-barrel/

$15 at Palmetto State.