AR build in MA. Now AR-9!

pretty nice for the factory.
i did not see much benefit from using 143 vs 140gr, and stick to 140gr. i bet if you will play with reloads you will shrink that group down quite a bit.
i posted that before, but, anyway - it may help if you did not see it before:

i stuck with 41.8gr loads of R16 and it is so far working out pretty damn good.
Yeah. I think the 140gr has slightly better BC, but not as good as the 147gr. I've also seen gel testing of the 143 ELD-X vs 140 ELD-M and they are very close in performance. 140 just seems to be a pretty good all-around go-to and the bullets are a lot easier to come by.

Maybe I'll try playing with 147gr down the line if it can be loaded to mag-length. But probably won't do it anytime soon.

Edit: I'm surprised, looking over that list, at how popular the small rifle primer 6.5 CM options were. I would have thought large rifle primers would provide for more consistent burns and MV, compared to small rifle primer. But if small rifle primer are being effectively used, I think I'll go that way when getting new brass. Then I can just use my 5.56 primers.
 
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Called the shop a few days ago after a 3 week wait. He said the guy hadn't even started yet but should start this week! The communication and time for work to be completed could certainly be better. I did just get the new PRS stock in so I may swing that by and add it to the build.

Anyone have a good truck for snugging up Magpul rifle stocks? My Ar-15 has a little wiggle. It's like ones its all assembled I need to somehow snug up the buffer tube while not rotating the stock.
Some magpuls have little leaf springs of sorts to keep tension. But some do not. I agree with paul73, some tape under it will tighten it up.
 
Some magpuls have little leaf springs of sorts to keep tension. But some do not. I agree with paul73, some tape under it will tighten it up.
Yep, some tape or some thin rubber sheet (old bike inner tube, rubber gasket material, etc.) For range blasters I usually don't give a crap, but for anything I want for precision I'll take out all the wiggle wherever I find it, including the stock. If there is any upper to lower wiggle, I'll slip an O-ring over the front upper trunnion.
 
I'll give the tape a shot. It's like it's got room to twist. So I I have to get heat on the loctite screw securing the two together.
I also tried one of the pieces to snug up lower to upper fit. It was a cheap 3d printed knock off and it broke. My new AR-10 with Aero parts has that spot for the tension screw but do I need to order the screw separately?
 
I'll give the tape a shot. It's like it's got room to twist. So I I have to get heat on the loctite screw securing the two together.
I also tried one of the pieces to snug up lower to upper fit. It was a cheap 3d printed knock off and it broke. My new AR-10 with Aero parts has that spot for the tension screw but do I need to order the screw separately?
Not sure about the set screw for the upper/lower fit.

But one make-shift solution I recently heard about is to put a dab of hot glue from a glue-gun down where the takedown pin section goes, and let it cool down with the upper and lower fit together. It's like a custom accuwedge. Though, I haven't tested it yet to see how well the glue dab stays in place when you lift the upper after it cools.
 
how popular the small rifle primer 6.5 CM options were
it produces much better ES/SD with the #450 primer than LRP #200 does. i used same load on both and from bergara it was same accurate, so, no loss of function there, SRP or LRP.
i have both kinds of brass now and shoot it indiscriminately of what primer is there, works same well.
dunno wtf i was testing there, it is quite typical for how it groups at 300yds. it was LRPs #200 group of 10.
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i remembered what i was testing - this brake - and it is on a very good sale again, at $81. i do recommend it.
 
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So KC small arms is having an issue with my build. They adjusted the gas block and now they're going to check the hole on the barrel. It's a criterion so of all the parts to be off spec I'd have guessed that last... We'll see!
 
I'm pondering on a build myself now.
Just because of the potential incoming ban.
Might be picking up an upper and lower real soon.
Since I cant swing $1500+ for a G3 clone or M1A that fast.
 
it produces much better ES/SD with the #450 primer than LRP #200 does. i used same load on both and from bergara it was same accurate, so, no loss of function there, SRP or LRP.
i have both kinds of brass now and shoot it indiscriminately of what primer is there, works same well.
dunno wtf i was testing there, it is quite typical for how it groups at 300yds. it was LRPs #200 group of 10.
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i remembered what i was testing - this brake - and it is on a very good sale again, at $81. i do recommend it.
I'm a fan of VG6 brakes, though I have not tried a Lambda yet. I have good results from the Epsilon and Gamma.

I'm using a 'Cookie Cutter' on a 300 BLK pistol- mainly because it's very, very loud LOL. Does a good job as a brake too, but I don't think it's a 'precision' option.
 
KC small arms actually called me with an update!(after I called earlier today and got nothing). Apparently the Criterion barrel gas port is only .080 but it should be in the .084-.092 range or something. I've reached out to Criterion....
 
KC small arms actually called me with an update!(after I called earlier today and got nothing). Apparently the Criterion barrel gas port is only .080 but it should be in the .084-.092 range or something. I've reached out to Criterion....
It does not cycle only 7.62 or both 308 and 7.62?
AR10 builds are that fun.
 
It does not cycle only 7.62 or both 308 and 7.62?
I can't answer that. They just informed me that it short strokes even with gas block maxed out. But either way the gas port seems to be undersized if their measurements are correct.
 
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I can't answer that. They just informed me that it short strokes even with gas block maxed out.
So you’re missing all the fun of doing it yourself I see. :).
Yeah, it it probably barrel port, may be getting it to .85 would be enough, but, you need to discuss with them what load you want it to be tuned for, ideally.
 
So you’re missing all the fun of doing it yourself I see. :).
Yeah, it it probably barrel port, may be getting it to .85 would be enough, but, you need to discuss with them what load you want it to be tuned for, ideally.
Unfortunately my cheapy armorer's wrench wouldn't fit over the barrel! I'm hoping the adjustable gasblock allows me to tune it in once I figure out what I'm actually going to be shooting etc.
 
Good luck with your build, I put one together recently that was a lot of fun. I went with a Superlative Arms adjustable gas block, and was able to really fine tune the stroke. The biggest pain in the ass for me was discovering a lot of high BC projectiles don’t ride the feed ramps and the chamber feed cone well. My first barrel was a Faxon match series big gunner, and it absolutely mangled the plastic tips of the ELD-M bullets. I tried polishing the feedramps, experimenting with different COALs, and eventually gave up. Tried again with a Wilson Combat barrel, and had similar issues. I contacted Wilson for advice, and they recommended the Hornady 140g BTHP at 2.80”, and I finally achieved success. I’m using all my ELD-Msin my bolt action Creedmore now.
 
Was dickering with the “Big Bitch” today and was pleasantly surprised by the about inch group at 200 on my second string.

57DD8895-D085-4A6C-9549-6DB4709AC722.jpeg

Moved over to the 400 for the last 4 rounds I had of 178s
8E3C0E47-5D40-4122-AFDE-4B5A599692B5.jpeg

Then shot a handful of 168s
B5A7032E-7E4D-4B1F-830F-B200F0E085BF.jpeg

That last string had guys a couple pits over using tannerite so I’m just going to assume that left one was from that.

I should have brought more ammo…

764FD855-7FD5-46F4-A959-852ED86DED4B.jpeg

Edit: I need to start logging days, weather, and scope adjustments. Temperature and precipitation differences from when I zeroed resulted in about an inch and a half shift up.
Would be good to know if a pattern develops in where my zero moved based on time of year.
 
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Jealous of that range. I only have access to 100 maybe 200 if i ask someone nicely
If I could string together enough open weekends I wouldn’t mind offering a trip up to Londonderry, but I have too much house shit to do now the weathers cooled. Only got up there today because wife cancelled plans because she thought she was coming down with something.
 
Rifle is coming home today. I've been slacking on optic. For under $1000 vortex viper.
you should have gotten that arken ep5 when i sent a message for 25% coupon. you would like it better.
not if anything is wrong with the viper, of course.
 
you should have gotten that arken ep5 when i sent a message for 25% coupon. you would like it better.
not if anything is wrong with the viper, of course.
I know. I have so much going on I'm trying not to spend money until the larger stuff is settled. But with the rifle done I'm getting itchy!
 
I know. I have so much going on I'm trying not to spend money until the larger stuff is settled. But with the rifle done I'm getting itchy!
i get it. i have nothing against top tier expensive glass, but, when collection grows above certain threshold, you kinda start counting $. :)

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i get it. i have nothing against top tier expensive glass, but, when collection grows above certain threshold, you kinda start counting $. :)

View attachment 658683
Trust me I'm not going for top tier anything on this build. Except for the barrel which had to be sent back 🤣
My longost range is just over 400yds but I'd really like 25x just to see what it's like.
 
Trust me I'm not going for top tier anything on this build. Except for the barrel which had to be sent back 🤣
My longost range is just over 400yds but I'd really like 25x just to see what it's like.
so, are you still on criterion barrel there? did shop break it in? still make sure to clean it after each first couple of shots.
 
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