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308 AR10 Build Info/Picture Thread

My Faxon 308 barrel was a nightmare from the get go, besides the shotty finishing, the gas port was too small, and in the wrong location also... the gas tube was a bit short so I got the Wilson longer one and then it was too long. Still didnt eject so drilled the gas hole out. Finally got ejection dialed in and then started to address the fail to feed which i thought was a magazine issue, tried different ones no change, then polished the ramps, no change.... I got a bullet from a gun store (I dont have reloading stuff) and glued it in a spent shell and got real close inspecting its operation manually by pushing the dummy round in with a pencil so I could watch and sure enough.... no taper on the breach.
My problems and emails to them were in may and june...... the chat on the webpage would get through..... then nothing.... Till November when this guy finally replied... I had long past returned it and already gotten another one, and it was NOT a magazine issue.

This is their reply when asking about the tapered feed. Reply came a month after i posted that video and had even sent them the link.

Hi Marty,



My apologies for the delay! We have done a fair bit of testing on the "feed cone" at the breech end of the barrel and found that it can aid in feeding cartridges in some situations, but generally it presents a new set of problems in terms of accuracy and occasionally pressure. Since the rounds are still impacting the breech face they can be deformed slightly or even set back some. If you are primarily shooting M80 ball, this probably won't cause any noticeable issues, but it can be quite problematic with match or soft point/open tip ammunition. It can be especially problematic with polymer tip ammo as the polymer plug will often be pushed totally out of alignment or even broken off during the feed cycle.



In this same testing we noted that the main determining factor for whether a cartridge would properly enter the chamber or impact the breech face was it's presentation from the magazine. If the cartridge is held too high it will not "nose up" enough to reach the chamber and impact the breech face. We then tested various methods of lowering the presentation height and found that either modifying a magazine or the magazine catch to present the cartridge .005" to .010" lower will reliably solve the feeding issue. We also found that this issue tends to follow lower receivers but not barrels (we had barrels returned with this issue reported but could not replicate them on any of our testing receivers, but we have also had a receiver that would display this issue on any barrel/upper we installed on it). We have occasionally seen individual magazines cause the issue, but this seems fairly rare.



As for finding a favorable resolution for you with this particular barrel we do only have a couple of options. Since we can only issue a credit against an order in our system, we don't have a way of getting a refund directly to you (we can credit AT3 on their order, but we don't have a way to ensure they issue a credit to you), we are left with exchanging the barrel. We can exchange it for another of the same barrel or any other item in our catalog (or combo of items to get the full value). If you let me know what you would like in exchange for the .308 barrel, I can arrange to get it sent out as the "replacement" under our warranty policy.


Regards,


upload image
Martin W.
Product Support Specialist &
Specialty Sales Associate
Faxon Firearms
 
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I’m a tinkerer at heart and don’t like giving up on a problem I really want to pull that extension and chamfer that chamber just to see if I can fix the issue. As a single feed rifle this barrel shoots amazing. All my other barrels have a chamfered chamber. But I’m not really wanting to gamble a barrel on it right now. And while I feel relatively confident I can do it, I am self-taught and the chance of ruining it are a possibility.
This was just one of the groups during a trip to try and figure out the issue. I had multiple groups like this but only way was single feeding it. This is the only reason I didn’t just jerk the barrel off and send it back immediately.
IMG_4076.jpeg
 
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I’m a tinkerer at heart and don’t like giving up on a problem I really want to pull that extension and chamfer that chamber just to see if I can fix the issue. As a single feed rifle this barrel shoots amazing. All my other barrels have a chamfered chamber. But I’m not really wanting to gamble a barrel on it right now. And while I feel relatively confident I can do it, I am self-taught and the chance of ruining it are a possibility.
This was just one of the groups during a trip to try and figure out the issue. I had multiple groups like this but only way was single feeding it. This is the only reason I didn’t just jerk the barrel off and send it back immediately.View attachment 8592668
What mags are you running?
 
I’m a tinkerer at heart and don’t like giving up on a problem I really want to pull that extension and chamfer that chamber just to see if I can fix the issue. As a single feed rifle this barrel shoots amazing. All my other barrels have a chamfered chamber. But I’m not really wanting to gamble a barrel on it right now. And while I feel relatively confident I can do it, I am self-taught and the chance of ruining it are a possibility.
This was just one of the groups during a trip to try and figure out the issue. I had multiple groups like this but only way was single feeding it. This is the only reason I didn’t just jerk the barrel off and send it back immediately.
if you pull the barrel extension off, be prepared with some very thin shims, e.g. 0.001" or so, when you re-assemble the barrel and torque the living daylights out of the barrel extension, it might go beyond it's original clocking, and your headspace might be too tight, so you might need to shim it to restore your HS. Typically when you retorque something it goes just a little bit more as the threads mate better.

just my 2 cents.
 
if you pull the barrel extension off, be prepared with some very thin shims, e.g. 0.001" or so, when you re-assemble the barrel and torque the living daylights out of the barrel extension, it might go beyond it's original clocking, and your headspace might be too tight, so you might need to shim it to restore your HS. Typically when you retorque something it goes just a little bit more as the threads mate better.

just my 2 cents.
Not to mention gas port alignment.
 
Yeah. I thought about the whole gas port alignment when reassembling. I’m not going to be messing with this barrel. It’s already boxed up and ready to go back. I do appreciate everyone’s help and insight on the issue though. Even if we didn’t come to a solution other than the one I’m currently about to do.
Thanks again. This place is wealth of knowledge and experience.
 
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I'm brand new to the AR 10 platform but just picked up a MEGA monolithic rail that someone put a Noveske 6.6 CM barrel on. Im in love and it shoots basically one large hole at 100. I saw earlier in the thread that many of you have, or had, MEGA rifles. I got the idea that it would be nice to have 308 capability so I'm thinking rather than get into changing barrels (I'm mechanically retarded) it might be easier to just get another upper. Will most uppers interchange easily with a different make or is that a headache? If that will work is there anything else that would need adjusted, changed, or otherwise fucked with? Any and all suggestions welcome, especially on 308 upper makes that might work.

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I'm brand new to the AR 10 platform but just picked up a MEGA monolithic rail that someone put a Noveske 6.6 CM barrel on. Im in love and it shoots basically one large hole at 100. I saw earlier in the thread that many of you have, or had, MEGA rifles. I got the idea that it would be nice to have 308 capability so I'm thinking rather than get into changing barrels (I'm mechanically retarded) it might be easier to just get another upper. Will most uppers interchange easily with a different make or is that a headache? If that will work is there anything else that would need adjusted, changed, or otherwise fucked with? Any and all suggestions welcome, especially on 308 upper makes that might work.

View attachment 8597920
View attachment 8597921
if you're mechanically handicapped (being polite here), then you should stick with a MEGA upper for your 308. One of the common wisdoms for the AR-308 platform is that you should match upper and lower brands, due to idiosyncracies of individual mfrs, and there being no real set standard other than the former, not the revived, DPMS LR-308, and Armalite AR-10.

some of those idiosyncracies manifest themself in the radius of curvature for the buffer tube mount at the back of the receiver, also, the receiver bore axis height over the receiver flat mating surface, also, the width of the receiver flat mating surface (this being cosmetic). might be other nuances, but those first two for sure will bite you in the as$.

unless somebody you trust tells you that Brand X will fit guaranteed no problem with the MEGA lower.
 
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if you're mechanically handicapped (being polite here), then you should stick with a MEGA upper for your 308. One of the common wisdoms for the AR-308 platform is that you should match upper and lower brands, due to idiosyncracies of individual mfrs, and there being no real set standard other than the former, not the revived, DPMS LR-308, and Armalite AR-10.

some of those idiosyncracies manifest themself in the radius of curvature for the buffer tube mount at the back of the receiver, also, the receiver bore axis height over the receiver flat mating surface, also, the width of the receiver flat mating surface (this being cosmetic). might be other nuances, but those first two for sure will bite you in the as$.
Thanks, thats what I sort of suspected. Any suggestons, other than Gunbroker, where I might find a MEGA upper?
 
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I've had several AR10 type rifles in the past and always got rid of them because of the weight. I decided to build a lighter weight AR10/AR308 pattern rifle and it came in at 7.8lbs bare, 10.4lbs loaded. I can't complain. Great shooter and very handy.
1000008651.jpg
 
I've had several AR10 type rifles in the past and always got rid of them because of the weight. I decided to build a lighter weight AR10/AR308 pattern rifle and it came in at 7.8lbs bare, 10.4lbs loaded. I can't complain. Great shooter and very handy. View attachment 8597940
Nice, You nailed it, the MEGA is a heavy beast but shoots well.
 
The barrel is where I lost most of the weight, about 2lbs. Went with a 16" Wilson Combat 6.5 CM that shoots great. I could shave about 12oz going with a different handguard and prob 1.5lbs if I went to carbon fiber stuff, but CF is expensive for not much gain. This sucker balances great with the suppressor and, so far, I'm happy.
 
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The barrel is where I lost most of the weight, about 2lbs. Went with a 16" Wilson Combat 6.5 CM that shoots great. I could shave about 12oz going with a different handguard and prob 1.5lbs if I went to carbon fiber stuff, but CF is expensive for not much gain. This sucker balances great with the suppressor and, so far, I'm happy.
Where did you get your WC barrel?
 
As stated above, the differences may be slight, but could make a HUGE difference. I have a very nice Aero M5E upper that will only fit(attach) my PSA PA10 lower if I tapped the take down pin in. I could prob dremel a little off to make it fit but decided to just sell it. The matching PSA PA65 upper fits like a glove and all lines match up.
 
I've had several AR10 type rifles in the past and always got rid of them because of the weight. I decided to build a lighter weight AR10/AR308 pattern rifle and it came in at 7.8lbs bare, 10.4lbs loaded. I can't complain. Great shooter and very handy. View attachment 8597940
Just saw this on on my olcal gunsite, looks nice...

The REVOLUTION uses a 5.56 bolt carrier and other 5.56 parts allowing for a shorter overall receiver size and reduced weight. This also isn’t a normal small frame .308, it’s smaller! It features many 5.56 parts; such as charging handle, bolt carrier, cam pin, buffer, heat sink barrel nut, handguard, and 5-position gas piston operating system. The barrel extension, bolt assembly, upper, and lower receiver are the exact same size as those on an AR15. Weighing in at 7.3 lbs. the Revolution features our new Edge Handguard with four built-in QD mounts, and is packed with all you’ve come to expect from POF-USA. Fully ambidextrous billet receiver set, nickel plated bolt carrier, 5-position adjustable gas piston, single stage match grade trigger, and more.
1737555221457.png
 
Just saw this on on my olcal gunsite, looks nice...

The REVOLUTION uses a 5.56 bolt carrier and other 5.56 parts allowing for a shorter overall receiver size and reduced weight. This also isn’t a normal small frame .308, it’s smaller! It features many 5.56 parts; such as charging handle, bolt carrier, cam pin, buffer, heat sink barrel nut, handguard, and 5-position gas piston operating system. The barrel extension, bolt assembly, upper, and lower receiver are the exact same size as those on an AR15. Weighing in at 7.3 lbs. the Revolution features our new Edge Handguard with four built-in QD mounts, and is packed with all you’ve come to expect from POF-USA. Fully ambidextrous billet receiver set, nickel plated bolt carrier, 5-position adjustable gas piston, single stage match grade trigger, and more.
View attachment 8598383
Oh yeah. Super nice and expensive. I can build almost 3 PSA AR10's for the cost of one of those, but they sure are nice. The Ruger SFAR is basically the same thing.