AR-10 build (sort of) for under $700

Liberty97045 · Jul 31, 2015

I know that this is not technically "a build" but I got a couple of great deals to put together a complete AR-10 for a very reasonable price.
Complete upper assembly $449.99 + $17 shipping
Complete lower assembly F2F $200 NIB ($239.99 retail)
Magazine $18
Total $684.99

The upper will arrive Monday, I owe you a picture and a range report next week

Machined from Aluminum Forgings 7075-T6
Hardcoat Anodizing: MIL-A-8625F, Type III, Class 2
Milspec diameter Receiver Extension
M4 Stock
Staked M4 Lock Nut
Standard Heavy Carbine Buffer
Caliber: .308

SKU: 507388
Barrel: 416R Stainless Steel
Barrel Length: 18"
Chamber: 308 Winchester
Twist Rate: 1 in 10"
.750" Gas block Diameter
Mid length Gas system
Forged upper receiver
T-marks
Forward Assist
Ejection Port Cover
A2-style Flash Hider
Magpul MOE Black Midlength Handguard

ZA_Survivalist · Jul 31, 2015

Is this a true AR10 spec reciever or an LR308 type?

Im not super familiar with AR10 variants but seek to get into them here soon. This is a killer deal!

oli700 · Jul 31, 2015

nice deal !

B5Ben · Jul 31, 2015

PSA is more along the lines of an LR308 but that is the problem with the AR10 realm, there isn't a standard like the mil spec AR15's. I went all PSA just to ensure there weren't any compatibility problems. I think this is a great deal and less than I paid but I also got the Midwest industries free float hand guard upper. The only issue I have had is that there isn't a BAD lever on the market that will work with PSA that I have found. I tried magpul, Troy, and phase 5. None of them worked due the proprietary bolt catch that PSA used.

Member 5605 · Jul 31, 2015

Awesome, that's the same build route I want to go. It will match my AR nicely.

mjbskwim · Jul 31, 2015

B5Ben said:
PSA is more along the lines of an LR308 but that is the problem with the AR10 realm, there isn't a standard like the mil spec AR15's. I went all PSA just to ensure there weren't any compatibility problems. I think this is a great deal and less than I paid but I also got the Midwest industries free float hand guard upper. The only issue I have had is that there isn't a BAD lever on the market that will work with PSA that I have found. I tried magpul, Troy, and phase 5. None of them worked due the proprietary bolt catch that PSA used.

Yeah I looked at it like there wasn't any conformity! But we got spoiled with AR 15s.Besides the AKs what other rifles are exactly alike?
You have to look harder for parts but it's still fun to be able to build a rifle.
You did good

Liberty97045 · Aug 5, 2015

I need some help with this. When I received the upper, there were some brass shavings on the bolt face from the test fire. I thoroughly cleaned the weapon before firing. I only shot 5 rounds and the fifth shot jammed. All the casings looked like they had rim damage so I am thinking that I have a rough chamber. I have read several things on polishing chambers. One technique involved a flapper wheel with 360 grit emery tape. The second involved a 45 caliber mop with polishing compound which seems like it would take forever. Anybody done this and care to offer your $0.02? When I get home I will try to post some helpful pictures.

edslhead · Aug 5, 2015

Mine did that right after I got it going. I tried a few things but what worked was lots a oil and shooting it. After a short break in it was fine.

B5Ben · Aug 5, 2015

I agree, keep shooting it. I had a similar issue on an Adams Arms AR15 that didnt run quite right until about 100 rounds were through it. Frustrated the crap out of me since it was essentially a fancy single shot for a short while due to FTE's, but once that period was over it been 100%. I have only few failures on the PA-10 and it too was early on.

Liberty97045 · Aug 5, 2015

So here we are, looks pretty rough. Opinions?

B5Ben · Aug 5, 2015

I have no experience polishing a chamber but am interested as it cant hurt. I'm also curious about the ring marks on the cases. My buddies 9mm AR had very similar marks and would like to know what they are from.

Swedish K · Aug 6, 2015

poor man's polishing concept - you might get a steel case and put a bit of polishing compound or even valve grinding solution - pop out the primer and drill it out - run a screw through the hole into a dowel and manually spin it like trying to start a fire with a fire drill by hand. I suppose you could use a drill to spin it but I'd try by hand first.

Of course you could contact PSA and see what they might do to fix it...

Stomper · Aug 6, 2015

Wow! Even my dog said that chamber is ROUGH!

Liberty97045 · Aug 6, 2015

B5Ben said:
I have no experience polishing a chamber but am interested as it cant hurt. I'm also curious about the ring marks on the cases. My buddies 9mm AR had very similar marks and would like to know what they are from.

I believe that the horizontal marks are from striking the deflector. I'm not sure it that is the right term. I am talking about the little wedge between the forward assist and the ejection door.

I discussed this with penalty box and I am going to try blueprinting it. Take a new shell, sharpie it all over, then feed it by hand and extract normally without firing. This should reveal any burrs, high spots or other problems.

I am thinking about starting with 360 grit and then moving to the mop dipped in automotive polishing compound to make it pretty. I will not be trying to polish out low spots, only high spots identified by blueprinting.

B5Ben · Aug 6, 2015

That could be true. In the case of my buddies 9mm AR, it was a slick side and didn't have a shell deflector but still could have been from impacting the ejection port itself.

I haven't seen that mark on any cases ejected from my PA-10 that I recall. I am curious to check my chamber to compare yours. I will post up some pics tonight when I do.

Liberty97045 · Aug 6, 2015

Here it is

Liberty97045 · Aug 6, 2015

I went for it and it worked so far.
First I tried cleaning the chamber more thoroughly. The I blueprinted a cartridge and while the shell dropped out with only a tap or two, I could see two scores.
I used my flapper with 320 emery tape for about 15 seconds.

It was definitely cutting so I stopped. And shot these five rounds.

Very little damage and no jam this time. I gave it another 30 seconds with 600 emery paper for a smoother finish.

spectra · Aug 6, 2015

Looks like you might have it figured out....

Have read many posts on a 308 forum that PSA does not mix well with other 308 builds......

I am sure they work fine but if building a .308 rifle stick with all PSA stuff or go another rout....

B5Ben · Aug 6, 2015

Looks great! I bet mine doesn't look that good from PSA. Will find out soon enough.

B5Ben · Aug 6, 2015

Well isn't as bad as yours was, but sure isn't as polished as yours is now. Glad to hear you got it tuned up. I didn't realize how difficult it was going to be to take a pic of a chamber. Keeping the flashlight and phone in just the right place long enough for it to focus is harder than I thought.

I also noticed a the barrel face is marred up. Will have to look into an AR10 vice block and wrench in order to fix that up.

Here is one in all of her glory