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Hello, new to the forum and new to AR10s…need some assistance please


MJV83

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Hey guys. My name is Matt. Joined the forum because I recently finished my first AR10 build and took it out yesterday for the first time. I’m not going to sugar coat it…I’m new to AR10s for sure, newish to AR15s and even new to guns in general. I live in the extremely restrictive state of NJ unfortunately, so that’s mostly what delayed me buying a gun for most of my adult life. I did grow up with a few guns as my father had a few shotguns and rifles. 
Anyway, I’m here to ask you guys for any help or advice you can offer.

Water Board stuff, I’ll try my best to not miss anything…but if you need more info, please just ask. I’m all ears and here to learn!!

First the gun itself;  
-Aero M5 Lower, Aero M5E1 upper, Ballistic Advantage 20” .308 Heavy profile Premium Series barrel, Ballistics Advantage BCG Black Nitride (came as a combo with the barrel), VG6 Precision Epsilon 762, Aero M5 complete .308 Rifle buffer kit, and Superlative Arms adjustable bleed off Gas block: 0.75” clamp on melonite (I started FULL OPEN and tried a few other adjustments. At full open is the only time it came even close to cycling)

1: Don’t have Armalite AR10 recoil system

2: Buffer Weight - 5.6oz

3: Buffer Length - 5.3”

4: Buffer Tube internal length - 9 5/8”

5: Spring, Length, Coils, Brand, Color - Spring came with the Aero M5 rifle buffer kit. It’s 12 3/4” long, 39 coils, Aero, and has a “bronze-ish” color

6: Gas System Length - Rifle

7: Gas Tube length - 15 3/16”

8: Photo into Mag well

F796E1BE-06CE-4B03-9E0B-5C3BBDA1050C.thumb.jpeg.2db27ae51f91c73b45f689d96013993d.jpeg

After attempting to take some fine measurements, I “believe” the gas block was too far back. I had it up against the shoulder but I believe it needs to be about 1/32” forward of the shoulder to line up properly. This may solve everything, but without going to the range, I don’t know how to tell for sure. Here is a second photo of the Mag well with the gas block moved forward 1/32”:

4F219B46-3DBB-4FE2-962B-5DB9E794BC2E.thumb.jpeg.b38a2e7620d90e36bc938ca4646a29ca.jpeg

9: Photo of Bolt Face:

0969D475-B119-42F8-98D3-70FBEA565A56.thumb.jpeg.259f4eb2b651ade6ef48388d6af33335.jpeg

10: Photos of BCG Clearance:

6A6C0A0A-B370-4E54-A308-10F92F8064AC.thumb.jpeg.070fa7df42b57c9877b5c372d34c8a3f.jpeg

AADE2F21-D2AC-476F-95B8-D59A37146FDB.thumb.jpeg.cf32f59ffa85c787f13a55588d116a57.jpeg

5D07F2F9-57D9-4E02-A103-5CCA648C399D.thumb.jpeg.0100dd4faa3e73576d4322b0c4efedb8.jpeg

11: Gas journal diameter - 0.75”

11a: Gas Port Diameter - Measured with a slide caliper, it’s 0.083”. A 5/64 drill bit fits with a little wiggle and a 3/32” drill bit won’t fit.

12: Description of Malfunction - When I went to the range yesterday, my rifle wouldn’t cycle properly, or at all, depending on the ammo. My first “guess” is that it’s under gassed…but as I mentioned, I’m new so rather get some input from all of you. I shot 40 rounds total yesterday: 20 rounds PMC Bronze .308, 147 grain FMJ-BT and 20 rounds of Ammo Inc 7.62/51, 150 grain FMJ (bought it bulk from PSA). With the PMC, the rifle would “attempt” to cycle but the BCG would never go back far enough to eject the casing and I’d end up with a “stove pipe.” With the cheaper Ammo Inc stuff, I don’t even think the BCG came out of battery, and if it did, just barely. It cycles completely fine by hand, no binding, BCG stays back with an empty mag. I put a lot of money into this build and wanna get it working correctly as soon as I can!! Thanks for any tips!!
 

13: Here’s the two types of ammo used:

4135723C-BD13-41D9-92F7-0DE2D9BBBF66.thumb.jpeg.f79ca07b04005b468ee9e22238e7fe12.jpeg

A204799C-C60E-4963-9877-1F1A36C0D380.thumb.jpeg.053dc6f1c71d9ac2ca18ce6b02d25c40.jpeg

14: Here’s a photo of the buffer and spring:

5160EF2E-16EF-41B2-80FB-764B92D74089.thumb.jpeg.b93e1e05fe94b59eb985d3f3c71a8965.jpeg

I think that’s everything with a few extra photos. If I missed something, let me know and I’ll add it asap. As mentioned above, it could be that the gas block was too far back, but without going back to the range (which is a pain in the ass in NJ), I don’t know how to make sure. I’d rather try to trouble shoot as much as possible before my next trip to the range.

Thanks everyone and I look forward to hearing from you and shooting the poop (no pun intended).

Matt-

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I realized that I didn’t post a photo of the “finished” rifle. Not that it will help with figuring out what I did wrong, but since this is my first post…I figured I’d share the final product with you all…hope you like it. It’s by far my favorite of what I own…just wish it ran properly!!!

F09FD0FF-98B6-4A72-93B1-6C799C95C2C0.thumb.jpeg.423a324002f7a9c0c97ce195db349e74.jpeg
 

i have changed the grip since this photo. Switch to a Hogue grip instead of the Magpul. 

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Thanks for the “welcomes” and for the tips. I’m really hoping it’s just that the gas block was out of alignment!! And yes, I’ve only shot 40 rounds of crappy ammo. Hopefully with some better ammo and more rounds…it will start to cycle properly. I was ready to drill out the gas port to 3/32” then I thought  I’d be better off trying to get some input prior to drilling anything!! 
 

If anyone else notices something that seems way off (ie. Wrong buffer or spring or something else), please let me know!! Otherwise, I’ll have to pick up some better ammo and try again with the gas block repositioned.

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Gas port is too small.  20" rifle gas on a 0.750" journal needs a port diameter that's 0.096", or damn close to that.  Yours is 0.010" too small, and that will cause the exact problems you're having.  Everything else in the build looks good.

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Welcome to the forum! So sorry you live behind enemy lines. I saw what was coming many decades ago and got the hell out. I still have family there and I think it must be like a coyote sitting on a cactus for them. I hear the stories and then look at their eyes when they come to visit in my free state and can't believe what we can buy over the counter. You know you can move, right? They'll tax the crap out of you to leave the state, but you can choose to live free or stay behind enemy lines. 

Can't help with the AR10 since I have a .300BLK AR where things are much simpler.

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11 hours ago, 98Z5V said:

Gas port is too small.  20" rifle gas on a 0.750" journal needs a port diameter that's 0.096", or damn close to that.  Yours is 0.010" too small, and that will cause the exact problems you're having.  Everything else in the build looks good.

Thanks!! I’ll drill it out to 3/32” (0.9375)…with that and moving the gas block slightly forward…hopefully all will function properly!! It may be a few weeks before I have a chance to get back to the range, but when I do…I’ll definitely report back!!

11 hours ago, Matt.Cross said:

Has anyone mentioned running it wet yet? Go heavy on the lube for the first 300 rounds. If that BCG isn't wetter than the swimming pool on the Titanic, you're not doing it right.

The BCG was literally dripping with oil that day at the range. But hopefully with the port opened to 3/32” and moving the block slightly, it will work.

I really appreciate the tips guys!! When I started this build, I had read that the AR10 is NOTHING like the AR15 as far as ease of proper function goes…I thought people were just being dramatic, but with the very little experience I have, I can see how finicky these things can be. 
 

I’m not one that’s into social media or forums at all, but I’m definitely glad I found this one. Much appreciation to everyone for the help and the welcomes!! I will let you guys know how it works out next time I make it out to the range!

11 hours ago, BrianK said:

Welcome to the forum! So sorry you live behind enemy lines. I saw what was coming many decades ago and got the hell out. I still have family there and I think it must be like a coyote sitting on a cactus for them. I hear the stories and then look at their eyes when they come to visit in my free state and can't believe what we can buy over the counter. You know you can move, right? They'll tax the crap out of you to leave the state, but you can choose to live free or stay behind enemy lines. 

Can't help with the AR10 since I have a .300BLK AR where things are much simpler.

I know I don’t have to stay here and I have considered moving out of this hell hole and still am considering it. The only thing that’s really keeping me here is that 95% of my family is still here. If it gets much worse, I might have to get out…but who knows, maybe it will turn around?? I doubt it, but with how fucked up Phil Murphy (Governor) is, I “think” a lot of the people here are fed up and ready for a change…

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  • 5 weeks later...

I hopefully will FINALLY be able to get back to the range this coming Friday!! Yay!! Anyway, hoping with the drilled out gas port (thanks @98Z5V for the tip) and better aligning the gas block with the port…fingers crossed, it will cycle properly!! If I do make it to the range on Friday, I will report back with my success, or failure/back to the drawing board. I’ll be bringing more variety in terms of ammo this time, including some newly reloaded ammo as I finally have my reloading setup up and running. Thanks to all who gave me tips with that!! 

D80330C4-EE68-471C-942A-9CB4BDC86602.thumb.jpeg.668ec08a3af78da640dc0b570a9cf8ae.jpeg

Here’s my new reloading setup!!

image.thumb.jpg.29877ecc3c461bb49a70e98cc1bd085a.jpg

And my first .308 rounds!!

I did plan on only reloading 308 at first  when I decided to start reloading…but I couldn’t help myself and got the stuff to do 223 as well…

image.thumb.jpg.35f2bb2b2b7898546a366a22555631f8.jpg

 

Anyway, hopefully all goes smoothly at the range on Friday!! Thanks again to all who provided input, tips, cautions, etc…

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Went to the range today….and she’s running like a top now!! Thank you all for the help!! And thanks @98Z5V for having me drill out the gas port. I put about 150 rounds down range and didn’t have a single hiccup! Cycled perfectly, extracted perfectly, locked back on an empty mag…tested with 3 different types of factory ammo and 2 different hand loads. All of which performed perfectly. Granted, the groupings weren’t great…around 1.5-2.5 MOA @ 100 yards (depending on the ammo)…but considering this is the first time I had it running properly, and using several different loads, I’m plenty happy with that for now.

Now, onto the next step. I’m not at all “seasoned” with adjustable gas blocks. In fact, this is the only one I have. All my AR15s have standard gas blocks. So, I have a superlative arms adjustable bleed off gas block. As I now have zero issues with the rifle cycling properly, I’m guessing it’s time to get the gas block setup properly, or close to it at least…as I assume it may need slightly different settings for different loads.   Today, I ran it full open with no bleed off and it was throwing the brass at 4-5 o’clock, so maybe theres not much adjustments needed?? With this gas block, I can close it off some (restrict the flow) or bleed off some. According to superlative arms, they say to use the bleed function, rather than the restrictive function as it’s easier on the rifle components. That makes sense to me…anyone disagree with that? And, as far as adjusting it goes, from what I’ve read…I just start slowly opening up the bleed off function little by little until it stops cycling, then go back towards full open a few clicks, and “done.” Does that sound right? Again, this is my first adjustable block and with the bleed off…it just complicates it a little more. So I wanna make sure I’m doing it properly. Any input you guys have would be appreciated!! 

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3 hours ago, MJV83 said:

I just start slowly opening up the bleed off function little by little until it stops cycling, then go back towards full open a few clicks, and “done.” Does that sound right?

If it will stop functioning. I have not been able to bleed enough gas off on a 308 build to get there, 5.56 it does just like they say but 308 no way. Also pay attention to the path of the bleed off gas, it will remove finish or tear up a cover on a suppressor if close enough.

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1 minute ago, jtallen83 said:

 Also pay attention to the path of the bleed off gas, it will remove finish or tear up a cover on a suppressor if close enough.

I appreciate the tip, although being in NJ, “silencers” make the rifle “silent” and therefore, in the minds of our idiot government in NJ…only a criminal would need a “silent gun.” So, therefore…not aloud in NJ (1 of 8 states left that have a ban on them). It has NOTHING to do with someone wanting to reduce the decibel level to a less ear damaging point…gotta love the Libs…

i do appreciate the tips!

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