PSA AR 10 feed problems

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[ARCHIVED THREAD] - PSA AR 10 feed problems

Posted: 1/14/2017 1:44:06 PM EDT

I have a complete 7.62x51 PSA setup upper, lower, bolt group only non PSA parts are Heavy buffer & spring and Magpul PRS® Precision-Adjustable Stock, PMAG 10 LR/SR plastic mag (**edit **originally wrote Magpul Mag). I fired my rifle for first time it wont feed the second round. It fires a sigle shot fine and bolt hold open catch is functioning properly.

My first question how wet should the action area be especially on a new gun? It wasn't wet, just lubed.

Will going back to a stock buffer allow it to feed better?

Posted: 1/14/2017 1:55:38 PM EDT

[#1]

Brand new rifles and builds should be soaking wet during initial testing. So wet, after a few shots, oil oozes from every orifice.

It's a pain if you're bothered by oily, grimy hands. But necessary to insure pepper function and break in. Lots say no break in period needed, but that's bull. They are new parts that need to work together. EVERYTHING mechanical needs a break in period UNLESS it's so finely and precisely machined to exacting tolerances. Which, we all know, these rifles are not.

Your heavy buffer should be fine as long as its an AR10 rifle buffer, which it must be if your bolt is locking back correctly.

Posted: 1/14/2017 3:42:44 PM EDT

[#2]

Quote History

Quoted:
Brand new rifles and builds should be soaking wet during initial testing. So wet, after a few shots, oil oozes from every orifice.

It's a pain if you're bothered by oily, grimy hands. But necessary to insure pepper function and break in. Lots say no break in period needed, but that's bull. They are new parts that need to work together. EVERYTHING mechanical needs a break in period UNLESS it's so finely and precisely machined to exacting tolerances. Which, we all know, these rifles are not.

Your heavy buffer should be fine as long as its an AR10 rifle buffer, which it must be if your bolt is locking back correctly.

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Thanks, will lube her up so she is dripping wet then I will runs many rounds through her.....

Posted: 1/14/2017 4:02:51 PM EDT

[#3]

Out of curiosity, what magazines are you using with your rifle?

Don't be afraid to over lube the rifle. Unless you are using the rifle in very very extreme climates/conditions, extra lube will not hurt a thing.

I bought all my components directly from PSA. I built the lower and bought a complete 20" upper and am using the 308 rifle buffer and spring from PSA also. I have two PMag magazines and haven't had any problems with my rifle.

Posted: 1/14/2017 4:44:32 PM EDT

[#4]

I'm going to say you need a heavier buffer spring. I had the same issues with my AR-10 build, and I expected that as I had a light AR-15 carbine spring like my brother who had the same issues before me. He recommended the David Tubbs spring and I figured I give the light 15 spring a try first. No go. It didn't feed well, so I got the Tubbs spring and have had no issues since. FYI, my AR-10 has a carbine stock and a heavier 4.4oz buffer from CTD. There are numerous heavy springs out there I think, but my only experience is with Tubbs. It was about $30.

The AR-10 bolt is much heavier, of course, and it needs a heavier spring to push it back forward with enough force to strip the next round off the mag and send it home properly.

As far as lubrication goes, I drench my bolt in motor oil and let it drain off over-night. I work it by hand a lot and blow out with air and wipe down before shooting the first time. Motor oil is a good cheap product for guns in basic mechanical applications. It has good staying power. Don't use it in the cold.

John

Posted: 1/14/2017 5:23:28 PM EDT

[#5]

Quoted:
Out of curiosity, what magazines are you using with your rifle?
Don't be afraid to over lube the rifle. Unless you are using the rifle in very very extreme climates/conditions, extra lube will not hurt a thing.
I bought all my components directly from PSA. I built the lower and bought a complete 20" upper and am using the 308 rifle buffer and spring from PSA also. I have two PMag magazines and haven't had any problems with my rifle.

http://i577.photobucket.com/albums/ss215/12Bravo10/PA10_zps6qfk19kx.jpg

View Quote

I am using a 10 round PMAG LR/SR, mistakenly wrote Magpul in my post. I did have to clearance the mag slightly, in back side, to allow it to go up into the rifle so mag catch would lock.

Quoted:
I'm going to say you need a heavier buffer spring. I had the same issues with my AR-10 build, and I expected that as I had a light AR-15 carbine spring like my brother who had the same issues before me. He recommended the David Tubbs spring and I figured I give the light 15 spring a try first. No go. It didn't feed well, so I got the Tubbs spring and have had no issues since. FYI, my AR-10 has a carbine stock and a heavier 4.4oz buffer from CTD. There are numerous heavy springs out there I think, but my only experience is with Tubbs. It was about $30.
The AR-10 bolt is much heavier, of course, and it needs a heavier spring to push it back forward with enough force to strip the next round off the mag and send it home properly.
As far as lubrication goes, I drench my bolt in motor oil and let it drain off over-night. I work it by hand a lot and blow out with air and wipe down before shooting the first time. Motor oil is a good cheap product for guns in basic mechanical applications. It has good staying power. Don't use it in the cold.
John

View Quote

I have Slash’s XH rifle buffer and Spring, I think my problem is lubrication. I wanted to rule out something I may have missed in my build. I have done a 9mm pistol and rifle and a 45 pistol and all is good. With this caliber I didn’t want over look something. I will soak the bolt as you recommended.

Posted: 1/14/2017 5:29:37 PM EDT

[#6]

Hopefully it is something as simple as not enough lube. I am going to suggest trying a different magazine (if you haven't all ready) since you stated that you had to modify yours. Keep us posted on what you find.

Posted: 1/14/2017 5:41:59 PM EDT

[#7]

I'd be willing to bet it's the magazine not presenting the next round properly because the magazine is not positioned correctly.

I purchased a PA10 lower that wasn't machined properly to accept Magpul magazines. I wasn't going to modify all my mags so I ditched the lower...and the upper...and put the parts on an Aero M5 set. Zero problems later. Stock buffer spring.

I will also suggest oiling up the gun and hand cycling the action a few hundred times. Seems to break things in well. I'd not worry about the buffer spring at this point.

It might also be that the extractor is not catching the round, especially if the problem is common on one side of the magazine versus the other. You might pull the extractor, remove the second o-ring and try again.

Good luck!

Posted: 1/16/2017 9:38:01 PM EDT

[#8]

Is it failing to chamber the next round?
Mine had a crazy strong extractor, two springs and two o rings in it from PSA. I took all of them out except the long spring and it now chambers the next round everytime.

Posted: 1/25/2017 6:13:03 PM EDT

[#9]

I just got back from range. Still having problems but I think I can narrow it down. So I ran it wet, what is happening it can feed the 2nd round its just that the round and bolt dont seat fully in the chamber. Pressing the forward assist isn't enough. If I pull the charging handle back about and inch or so let it go and it will seat the bolt and the round. What has me puzzled is the gun works perfect to feed the first round. I can pull handle back and let her rip chambers perfectly, also can chamber 2nd and 3rd round this way (manually). Additionally, with bolt open I can insert mag just release the bolt with the bolt hold open catch (??) and that round is chambered fine.

Posted: 1/25/2017 6:17:16 PM EDT

[#10]

Quote History

Quoted:
You might pull the extractor, remove the second o-ring and try again.

Good luck!

View Quote

I will look into this as well.

Posted: 1/26/2017 11:04:41 AM EDT

[#11]

Are you still using the same magazine (modified) or have you tried other magazines yet? Sounds like a good idea to check the extractor like others have suggested.

Posted: 1/26/2017 2:40:35 PM EDT

[#12]

I bet it is a tight extractor. Using the handle it will chamber it properly but using the FA it won't. Mine did the same thing. My first issue with my pa10 was the bad headspace/chamber deal. And it wouldn't even chamber the first round. At least you don't have that problem. After psa fixed my pa10 then it did what yours did. Removed a o ring and installed a ar15 extractor spring. It's been flawless since.

Posted: 1/26/2017 9:19:36 PM EDT

[#13]

Could very well be the extractor as other have said. Make sure there's only one o-ring.

Also, I'd ditch the heavy buffer until the rifle is a little more broken in and you've got your other issues sorted out.

-Stooxie

Posted: 1/26/2017 9:57:47 PM EDT

[#14]

Ok will take the bolt apart and see what is in there. BTW I did remove the heavy buffer before shooting it this time.

I am still a little confused as to an alternative mag I would like to get a steel one. I have this one: Magpul PMAG Gen 3 DPMS LR308/SR-25 Pattern AR 308 Magazine

So do I use an SR 25 type; ASC SR-25 10 Round Magazine .308/7.62 Or an LR 308; ProMag, DPMS LR-308 Magazine, .308 Winchester/7.62 NATO Or this one ProMag, DPMS LR-308/SR-25 Magazine which is both LR308 and SR-25?

Posted: 1/26/2017 11:08:05 PM EDT

[#15]

The only .308 mags I have are pmags. Have a few 25 round, a few 20 round and a 10 round. I have never had a mag issue in my pa10. Before buying mags I would try the extractor mod first. Also I never changed the h buffer in mine.

Posted: 1/27/2017 2:27:51 AM EDT

[#16]

I had similar problems so I replaced extractor spring and o-ring with a sprinco ar10 kit and mine hasn't misfired once since.

Posted: 1/27/2017 10:02:24 AM EDT

[#17]

Last night I pulled the bolt apart and there was one (1) O ring with the extractor spring so I removed the O ring and put spring back in and reassembled it. Unfortunately to get to the range takes some doing, hopefully will get there by next weekend. Will update then. Thanks for all help so far.

Posted: 1/27/2017 10:35:24 AM EDT

[#18]

Quote History

Quoted:
Last night I pulled the bolt apart and there was one (1) O ring with the extractor spring so I removed the O ring and put spring back in and reassembled it. Unfortunately to get to the range takes some doing, hopefully will get there by next weekend. Will update then. Thanks for all help so far.

View Quote

If it still malfunctions your next step should be 1 o-ring with a ar15 extractor spring. That's what my pa10 needed.

Posted: 1/27/2017 2:00:36 PM EDT

[#19]

There is so much conjecture in this thread, without having a full picture of what is going on.

You start to see very quickly how bad advice can be thrown all over the place.

OP: You said you made modifications to the magazine.

What is it that inspired you to do that, and do you have pictures of before and after?

Magpul is the maker of the PMAG-same company.

Posted: 1/27/2017 3:38:08 PM EDT

[#20]

Quote History

Quoted:
OP: You said you made modifications to the magazine.

What is it that inspired you to do that, and do you have pictures of before and after?

Magpul is the maker of the PMAG-same company.

View Quote

All I did was take a small amount of material off the lower back end of mag, there was a beveled up plastic area that I removed with a dremel. Prior to the mod the mag wouldn't go in far enough to catch, the mag was tight against the lower. I slowly removed material until it would slide in and engage securely.

Posted: 1/27/2017 5:45:07 PM EDT

[#21]

After seeing how you modified the magazine, I'm thinking that it still might be hitting the bottom of the magwell and not fully seated or seated and a slightly off angle causing the feeding issue.. A different magazine (without the lip around it) would rule out any out of spec machining on the lower.

Posted: 1/27/2017 7:11:07 PM EDT

[#22]

Quote History

Quoted:
After seeing how you modified the magazine, I'm thinking that it still might be hitting the bottom of the magwell and not fully seated or seated and a slightly off angle causing the feeding issue.. A different magazine (without the lip around it) would rule out any out of spec machining on the lower.

View Quote

That is what I am thinking

Posted: 1/27/2017 10:56:43 PM EDT

[#23]

I'm using cproducts mags. I couldn't get the pmags to seat in my lower

Posted: 2/16/2017 11:08:48 AM EDT

[#24]

FFR5294,

Any updates? Did you try a different magazine or try any of the other suggestions?

Posted: 2/16/2017 11:54:31 AM EDT

[#25]

Quote History

Quoted:
I'm using cproducts mags. I couldn't get the pmags to seat in my lower

View Quote

Pmags work great in mine. I would start with the buffer and spring recommended by PSA. An SLR adjustable gas block should also be on the shopping list.

[ARCHIVED THREAD] - PSA AR 10 feed problems

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