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Old May 2, 2021, 09:23 PM   #1
ocharry
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First time ar build

OK guys and gals

I know this has been beat to death...but not for me..lol

I would like to ask for the wisdom of the crowd about my first AR build, so here we go

I am waiting on my bolt carrier group..it is a Griffen bolt carrier group....tracking says it should be here Tuesday..unless it falls into the black hole in St. Louis

But I have the upper ready to go I hope...I have the nose lapped with 80-90% flat and square and the green mountain barrel extension is a nice ring fit into the receiver....fits really nice and snug....everything else is done...dust cover, forward assist....so waiting on the bolt group so I can check head space before final assembly.....barrel is 18" rifle gas system ,gas block is fitted but not on at this time...also have auroshell 64 for barrel nut which I'm wanting to torque at 35-60 ftpd with receiver and barrel on a midwest industries action rod

So I guess the question to you all is....is there anything else I should do or check before I button this thing up ??

I know I'm itching to get this thing running....all of the parts are here and mock fitted or assembled....lol...gonna look good....all black...bolt and gas tube too....I want to call her midnight...lol....or black Betty..lol

So what is the wisdom of the crowd here??

Thanks
Ocharry
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Old May 2, 2021, 09:38 PM   #2
Shadow9mm
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Seems like you know what your doing. Best thing I can tell you is go slow, be methodical. If you run into a problem go to a tutorial and double check. Or better yet follow one as you are building. Go step by step, it will all come together just fine.
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Old May 4, 2021, 05:21 AM   #3
kymasabe
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Is the barrel dimpled? I may be paranoid but I worry about my gas blocks coming loose or not aligning properly, so I bought a Kaw Valley dimpling jig and I dimple my barrels. And, I blue-loctite the gas block set screws.
Barrel nut... I tighten 3 times. First 2 times to 30lbs and then loosen, then 3rd time I torque to final spec. I've found my builds tend to more accurate at lower torques, usually under 55lbs so if barrel nut timing allows, I try to keep my last torque in the 50-55 range.
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Old May 4, 2021, 05:45 AM   #4
stagpanther
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Quote:
unless it falls into the black hole in St. Louis
Ordered from Midway? That black hole is real, I've had packages lost for weeks, even months from there. Usually happens with anything that is handed off to the postal service from UPS or fedex. It becomes a magical mystery tour of who actually has it and who bothers to scan it. I've seen packages bounce back and forth, take side tours, go around in circles and sit at the destination sort center for a week. All the services are now seeking to charge an extra fee to get up to date accurate tracking information.
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Old May 4, 2021, 06:37 AM   #5
imashooter
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Sounds decent enough. Don't get too caught up in all the advice. Regarding the gb, I've done several with set screws. Dimpled one for the experience only. Never, ever, had one loosen. Just tighten the crap out of it and al should be well. You'll also run across info advising having a small gap (about thickness of business card) between the gb and adjacent shoulder. Again, I have only one following that protocol. All others butt up to the shoulder due to the optimum air flow when testing the fit. Just depends on the barrel and gb.
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Old May 4, 2021, 10:54 AM   #6
ocharry
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kymasabe....no i have not dimpled the barrel...but i really did think about it..i have tried to use all U.S.A. parts or made here and i think i have done that..the gas block is a Midwest Industries, along with their slim hand guard and it has 3 screws to hold it to the barrel journal, i had it just snugged when i set it up so when i took it off i marked it and the screws snapped when i loosened them...so i think i am going to try it with out dimpling...also i am kinda thinking it may void any warranty the barrel may have....but if i have trouble i can always go back and put one on the barrel if needed...also the gas block came with some stuff called Vibra-Tite...never heard of that stuff but from what i have seen i guess it is pretty good...so i will use that on the screws at final...was gona use red loctite but they sent this stuff with the gas block so thats what i will use for the set screws

stagpanther....not from Mid way,, the bolt came from Optics Planet as did most of the stuff..they do have a pretty good selection and the prices are pretty good too...i tried to catch the things i needed on sale too so that helped some...when i was thinking i wanted to build one of these rifles and started gathering stuff...man i tell ya....the shelves are pretty bare out there....started out i wanted a Wilson barrel...picked one that was outa stock..called and they told me 8-10 weeks out..back to looking...heck i didnt even know Green Mountain made AR barrels.. i do have a couple of their 22 barrels and they shoot pretty dang good..but most places were out of stock...anyway GM had this one and it was kinda what i wanted so i ordered it from them ...i went back 3 days later to look at the blue print they offer ...hahahaha...that barrel was sold out......so yeah i had to wait for most things...and the Griffen bolt group is the last piece.... i know Optics Planet dont have the best rep for shipping and most of the stuff from them, when they ship only takes about two days for me to get it, and all of the stuff i have gotten from them was free shipping and no tax...so from Mid WAY i have to add that to the price....the prices between the two are very comparable within a dollar or two...and if you think you are gona build one of these things cheap you better sit down and think it through...cheap aint in the mix...my budget is around $1000 and i tried to do it kinda cheap and still have a good shooter..you know catch things on sale , no tax, free shipping, that kinda stuff..ahahahahahaa....same thing happened when i built a 1911....ahahahahahaa....cheap my donkey...but its a dandy and a shooter...hoping the same for this rifle...they tracking said may 4...havent looked today but i doubt it shows up today...

imashooter...when i checked the gas block it did in fact need to be spaced off the shoulder....just looking through the set screw hole, so i made a spacer out of and old plastic card and checked it and it looked pretty lined up...so this block does need the space between the shoulder and the block...but it did not cover the hole when pushed all the way to the shoulder...i just feel better about it being centered

thanks guys...now if only i had a bolt..maybe i could click the heals of my ruby slippers and get it past St. Louis.....i would have the sheets full and healed over

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Old May 4, 2021, 07:58 PM   #7
Shadow9mm
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For the gas block. I would recommend dimpling the barrel. the Kaw valley jig works well.

If you dont want to use a jig, install the gas block and shoot the gun. make sure it runs.

Then take the gas block off. you will most likely has scoring on the barrel from the set screws. nice easy marks to drill.

Vibra tite will not work. It is released with heat like lock-tite.

If you insist on using a thread locker rocksett is the way to go. rated for very high temps. Only catch is you need to soak the part in hot water to release it.
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Old May 5, 2021, 11:15 AM   #8
ocharry
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Shadow... thanks for the insight....i have been back and forth in my head about the dimple thing..and i have come to the conclusion ... for me..since i dont plan on running this gun hard and the gas block has 3 set screws...no 3 gun or stuff like that...mostly hunting and i dont think the barrel will ever get to hot to touch, i think i am going to try and not dimple the barrel...and see what happens, its not that big of a deal for me if i need to dimple.....i did look at the fixtures for doing the job, but for me, i have a mill and a lathe and i thought about making a fixture but it would be just as easy to put it on the mill, tram the barrel and put in a dimple or two, but i think 1 dimple would work and that way if i ever change the gas block i dont have to worry about spacing to match...plus doing it that way i would have better control over what i am doing.

been retired for 6 years after 50 years of twisting handles...lol...guess i needed something to play with among all the other things i do..lol...so here we are......i dont really consider this building...more like assembling...lol...prolly get some grief over that one!!

but hey the good news is the bolt group is out for delivery today...so, on with the shew


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Old May 5, 2021, 02:01 PM   #9
rickyrick
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I align my gas blocks for best gas port clearance, snug it down and mark everything.
I then take one set screw out and dimple right through the set screw hole on my drill press.
I install the first one and tighten down properly and use high temp locktite.
Finally I repeat the process with the other screw.

Not sure if this is the best way, but it works for me. But I test it first before I dimple
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Old May 6, 2021, 11:30 AM   #10
Shadow9mm
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Quote:
Originally Posted by ocharry View Post
Shadow... thanks for the insight....i have been back and forth in my head about the dimple thing..and i have come to the conclusion ... for me..since i dont plan on running this gun hard and the gas block has 3 set screws...no 3 gun or stuff like that...mostly hunting and i dont think the barrel will ever get to hot to touch, i think i am going to try and not dimple the barrel...and see what happens, its not that big of a deal for me if i need to dimple.....i did look at the fixtures for doing the job, but for me, i have a mill and a lathe and i thought about making a fixture but it would be just as easy to put it on the mill, tram the barrel and put in a dimple or two, but i think 1 dimple would work and that way if i ever change the gas block i dont have to worry about spacing to match...plus doing it that way i would have better control over what i am doing.

been retired for 6 years after 50 years of twisting handles...lol...guess i needed something to play with among all the other things i do..lol...so here we are......i dont really consider this building...more like assembling...lol...prolly get some grief over that one!!

but hey the good news is the bolt group is out for delivery today...so, on with the shew


ocharry
For hunting use, just firing a few rounds here and there its probably fine.

With that said the issue is not the barrel getting hot, but the gas block itself. As it has a much smaller mass than the barrel, and is taking gasses directly off the barrel the gas block itself tents to head up much faster than the barrel. And if the gas block expands faster it can loosen on the barrel due to the faster heating especially if it is aluminum block on a steel barrel.

What I would suggest to keep it easy. Mount the gas block and shoot it to make sure it is correctly lined up and running properly. Then shoot maybe 10-20 rounds through it fairly quickly to heat the gas block up. then re-tighten the screws on the gas block while it is hot, being careful not to burn your fingers. That way it will be properly tight, even if the gun gets heated up.
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Old Yesterday, 09:26 AM   #11
ocharry
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thanks again Shadow...this gas block is a little longer than most and it is steel, so what you said sounds reasonable to me.. check the screws after it is warmed up....and the gas block getting hot faster than the barrel...i can see that too... for sure

but, if it even shows any sign of not staying where i put it it will get a dimple or a pin...i sure dont want to have the thing stop working.....especially if it happened right when i needed it to run

so with load development and getting it sighted in, i should have a good feel for what it is going to do i think....buy then i will either trust it or not and if not i will fix that

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Old Yesterday, 06:01 PM   #12
Shadow9mm
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Happy to help. I expect re-checking when warm will be perfect for what you are using it for. Keep us updated on how the build goes. And post pics when you get it done!
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