Warning

 

Close

Confirm Action

Are you sure you wish to do this?

Confirm Cancel
BCM
Durkin Tactical Franklin Armory
User Panel

Site Notices
Posted: 10/15/2015 6:47:11 PM EDT
I have just completed my PTAC Tac 10 build, have PSA parts for the most part (except for LPK and mag release, which were Seekins). Bought some SR 25 magazines (20 round) on Midway, they fit fine, release fine, but the bolt won't close with an empty magazine in place. Wondering if the follower is getting in the way, but don't really want to put a live round in the gun to see if it operates then (have not test fired the weapon). Any thoughts/suggestions?
Link Posted: 10/15/2015 8:43:25 PM EDT
[#1]
An empty magazine is supposed to hold the bolt open.

Edit: The bolt won't close even with pressing the bolt release?
Link Posted: 10/15/2015 10:50:10 PM EDT
[#2]
Yeah. That means it works. There is a bolt release lever on the left side of the gun.
Link Posted: 10/16/2015 6:35:00 AM EDT
[#3]
You really should have a few dummy rounds laying around if you get this AR assembly bug....

Oh, and the PSA/PTAC .308 use the Armalite AR-10 size/shape bolt hold open, not a regular AR-15 or DPMS pattern.
Link Posted: 10/16/2015 9:16:32 AM EDT
[#4]
When I have a magazine properly seated, and I release the bolt, it goes about half-way across the magazine. I used the proper (PSA supplied) bolt hold open. Time to run and get dummy rounds :)
I'll try and post a picture of what it does later, that may help.
Link Posted: 10/16/2015 10:45:02 AM EDT
[#5]
I am also building a PTAC/PSA .308, so far all PSA Parts. What barrel did you go with? or did you buy a complete upper?
I am leaning towards a Rainer Arms 18"or 20".
Mine so far, got a ways to go.
Link Posted: 10/16/2015 2:38:47 PM EDT
[#6]
Discussion ForumsJump to Quoted PostQuote History
Quoted:
I am also building a PTAC/PSA .308, so far all PSA Parts. What barrel did you go with? or did you buy a complete upper?
I am leaning towards a Rainer Arms 18"or 20".
Mine so far, got a ways to go.
http://i3.photobucket.com/albums/y86/bbush44/308AR/20150224_180126_resized.jpg
View Quote



I went with the PSA barrel and bolt, wanted to make sure on compatibility there.
Link Posted: 10/16/2015 3:04:51 PM EDT
[#7]
Which PSA Barrel did you go with? Range report when you make it out.

I've got the PSA BCG, I plan to keep mostly PSA on my build but read some users received tight chambers on the PSA 308 complete uppers.
Link Posted: 10/16/2015 6:06:03 PM EDT
[#8]
Try some Magpul magazines...........they work fine in my PA10
Link Posted: 10/16/2015 8:05:00 PM EDT
[#9]
I'm using magpuls as well without issue.
Link Posted: 10/18/2015 11:15:33 AM EDT
[#10]
In looking inside the chamber, it looks like the bolt carrier is getting hung up on the back side of the magazine. I can't get a good picture of it. Will report back when the Magpul comes in...Just to be sure, thee Magpul G3 is the correct mag for this rifle?
Link Posted: 10/18/2015 11:59:53 AM EDT
[#11]
The mags you mentioned in the first post are the same ones i have. If you could try and get some pictures it might help us see what the problem might be. I can get my bolt to hang up on the mag follower if i push the bolt release and ride the bolt forward with the charging handle.

Link Posted: 10/18/2015 12:52:37 PM EDT
[#12]
Link Posted: 10/18/2015 1:06:38 PM EDT
[#13]
Discussion ForumsJump to Quoted PostQuote History



As long as the bolt closes when loaded and holds open when empty then the mag is doing what it is supposed to do. PA10s have slight variations in dimensions from dpms, if those variations are causing what you are seeing with that particular mag/rifle combo then use different mags (if it bothers you). But it sounds like a non-issue...

I use ASC mags and they have functioned flawlessly so far as has my PA10.. I just picked up a pmag but haven't tried it at the range yet.
Link Posted: 10/18/2015 1:07:55 PM EDT
[#14]




In addition, the mag will not seat when the bolt is closed. This all makes me put my hopes on PMAG :)
Link Posted: 10/18/2015 1:13:52 PM EDT
[#15]
Does it still hang up if you don't ride the bolt forward? There really isn't a reason to ride the bolt forward.
Link Posted: 10/18/2015 1:31:10 PM EDT
[#16]
The bolt goes about 1/2 way across the magazine if the bolt is released by pusshing the button
Link Posted: 10/18/2015 1:44:54 PM EDT
[#17]
Discussion ForumsJump to Quoted PostQuote History
Quoted:
http://i1315.photobucket.com/albums/t600/MN05Wrangler/IMG_0016_zpshd8ozl7e.jpg

http://i1315.photobucket.com/albums/t600/MN05Wrangler/IMG_0015_zpsbvo1rnkl.jpg

In addition, the mag will not seat when the bolt is closed. This all makes me put my hopes on PMAG :)
View Quote


Will it seat if you slam the bottom? Sounds like spring tension pushing the rounds up into the bottom of the carrier.

Again if the mags are feeding without issue, use them for range mags and buy some Pmags, ASC or Cproducts mags. Pmags are $18. ASC are $15 (all stainless construction) and Cproducts are about the same.
Link Posted: 10/18/2015 2:35:25 PM EDT
[#18]
Discussion ForumsJump to Quoted PostQuote History
Quoted:
View Quote

Blew the picture up. but now you can clearly see the lips of the magazine are running into the bottom oft he carrier.  That would also explain why it is hard to insert a magazine.

EDIT: Looking at the other side of the magazine the feed lip look like that are in contact with radius in the upper,  There should be a slight clearance.  The magazine is inserted too far.  Either due to the magazine catch in the wrong place, or the hole in the magazine is wrong.

Check the position of the magazine catch.  The bottom of the catch should be .925" below the top shelf of the lower.  The top of the hole in the magazine should be 1.150" below the top edge of the feed lips.
Link Posted: 10/18/2015 6:20:39 PM EDT
[#19]
Are there different mag catches?
Link Posted: 10/18/2015 6:28:03 PM EDT
[#20]
Discussion ForumsJump to Quoted PostQuote History
Quoted:
Are there different mag catches?
View Quote

No.

Are the measurements off?
Link Posted: 10/19/2015 10:34:49 PM EDT
[#21]
Top of hole to top of feed lip is 1.16 on the mags, from the top of the magwell to the bottom of the mag catch is 0.924.

Can I file the hole in the mag up a bit to make it fit?
Link Posted: 10/20/2015 7:49:05 AM EDT
[#22]
Discussion ForumsJump to Quoted PostQuote History
Quoted:
Top of hole to top of feed lip is 1.16 on the mags, from the top of the magwell to the bottom of the mag catch is 0.924.

Can I file the hole in the mag up a bit to make it fit?
View Quote

No, don't do anything.  Those numbers are close enough to say the lower receiver and the magazines you measured are not the problem.

Is this a matched upper/lower set, or from two different manufacturers?

With the .308 ARs I would only get uppers and lowers from the same place, as there are slight dimensional differences that cause problems.

If the upper and lower are both from PSA, I would contact PSA about this.
Link Posted: 10/20/2015 11:39:30 AM EDT
[#23]
Discussion ForumsJump to Quoted PostQuote History
Quoted:
Are there different mag catches?
View Quote

According to http://palmettostatearmory.com/psa-pa10-upgrade-kit.html the PA-10 mag catch is special. Here is just the mag catch if that's all you need: http://palmettostatearmory.com/psa-pa10-magazine-catch.html
Link Posted: 10/20/2015 1:04:15 PM EDT
[#24]
Discussion ForumsJump to Quoted PostQuote History
Quoted:

According to http://palmettostatearmory.com/psa-pa10-upgrade-kit.html the PA-10 mag catch is special. Here is just the mag catch if that's all you need: http://palmettostatearmory.com/psa-pa10-magazine-catch.html
View Quote View All Quotes
View All Quotes
Discussion ForumsJump to Quoted PostQuote History
Quoted:
Quoted:
Are there different mag catches?

According to http://palmettostatearmory.com/psa-pa10-upgrade-kit.html the PA-10 mag catch is special. Here is just the mag catch if that's all you need: http://palmettostatearmory.com/psa-pa10-magazine-catch.html

The size and shape of the parts that lock the magazine in place is the same, the only thing different is the length of the threaded stud.

That just means when the catch is installed it is not flush with the top of the button.  The position of the feed lips relative to the lower is correct as verified by his measurements, the problem is in the upper or the mating of the upper and lower.
Link Posted: 10/20/2015 5:23:39 PM EDT
[#25]
Discussion ForumsJump to Quoted PostQuote History
Quoted:

The size and shape of the parts that lock the magazine in place is the same, the only thing different is the length of the threaded stud.

That just means when the catch is installed it is not flush with the top of the button.  The position of the feed lips relative to the lower is correct as verified by his measurements, the problem is in the upper or the mating of the upper and lower.
View Quote View All Quotes
View All Quotes
Discussion ForumsJump to Quoted PostQuote History
Quoted:
Quoted:
Quoted:
Are there different mag catches?

According to http://palmettostatearmory.com/psa-pa10-upgrade-kit.html the PA-10 mag catch is special. Here is just the mag catch if that's all you need: http://palmettostatearmory.com/psa-pa10-magazine-catch.html

The size and shape of the parts that lock the magazine in place is the same, the only thing different is the length of the threaded stud.

That just means when the catch is installed it is not flush with the top of the button.  The position of the feed lips relative to the lower is correct as verified by his measurements, the problem is in the upper or the mating of the upper and lower.


NEGATIVE. The bolt catch for the PA-10 is a unique part. You HAVE to use the PSA bolt catch for proper function.
Link Posted: 10/20/2015 8:44:30 PM EDT
[#26]
Discussion ForumsJump to Quoted PostQuote History
Quoted:


NEGATIVE. The bolt catch for the PA-10 is a unique part. You HAVE to use the PSA bolt catch for proper function.
View Quote View All Quotes
View All Quotes
Discussion ForumsJump to Quoted PostQuote History
Quoted:
Quoted:
Quoted:
Quoted:
Are there different mag catches?

According to http://palmettostatearmory.com/psa-pa10-upgrade-kit.html the PA-10 mag catch is special. Here is just the mag catch if that's all you need: http://palmettostatearmory.com/psa-pa10-magazine-catch.html

The size and shape of the parts that lock the magazine in place is the same, the only thing different is the length of the threaded stud.

That just means when the catch is installed it is not flush with the top of the button.  The position of the feed lips relative to the lower is correct as verified by his measurements, the problem is in the upper or the mating of the upper and lower.


NEGATIVE. The bolt catch for the PA-10 is a unique part. You HAVE to use the PSA bolt catch for proper function.

Yes, we know the bolt catch is special, read the bold....

Just checked with my PSA and plain ol' AR, and swapped magazine catches, they are same.
Link Posted: 10/22/2015 5:52:29 PM EDT
[#27]
The bolt catch, BCG, upper, lower, and barrel are all from PSA. The mag catch is from Seekins, and the LPK is a hodge podge of KNC and others.
Link Posted: 10/27/2015 11:33:21 AM EDT
[#28]
Discussion ForumsJump to Quoted PostQuote History
Quoted:
I am also building a PTAC/PSA .308, so far all PSA Parts. What barrel did you go with? or did you buy a complete upper?
I am leaning towards a Rainer Arms 18"or 20".
Mine so far, got a ways to go.
http://i3.photobucket.com/albums/y86/bbush44/308AR/20150224_180126_resized.jpg
View Quote



PSA website says that they will only guarantee proper fitment if you purchase their stuff, so I went with all PSA parts...
Link Posted: 10/27/2015 11:36:07 AM EDT
[#29]
Check Gas Tube Alignment.
Link Posted: 10/27/2015 11:38:03 AM EDT
[#30]
Follow-up... Magpul magazine fits fine. Have not had it to the range yet, so function is not confirmed, but the bcg moves over the mag, seems to work smoothly. Will add something when I take it out for a test drive. Thanks to all for their help with this!
Link Posted: 11/3/2015 10:55:50 PM EDT
[#31]
First 40 rounds through it, fired off the first few fine, then stovepiped a few rounds in a row. Lubed up the BCG and it cycled 5 rounds and stovepiped again. Gonna clean her up and try again later this week with different ammo. I did try it without the magazine in since I had mag issues earlier, still stovepiped. The rounds that did cycle flew out with authority. More to follow... Fun gun to shoot, for sure.
Link Posted: 11/3/2015 11:49:58 PM EDT
[#32]
Discussion ForumsJump to Quoted PostQuote History
Quoted:
First 40 rounds through it, fired off the first few fine, then stovepiped a few rounds in a row. Lubed up the BCG and it cycled 5 rounds and stovepiped again. Gonna clean her up and try again later this week with different ammo. I did try it without the magazine in since I had mag issues earlier, still stovepiped. The rounds that did cycle flew out with authority. More to follow... Fun gun to shoot, for sure.
View Quote

Sounds like mine when I took it out the first time. It's super overgassed and you'll need an adjustable gas block to turn it down.
Link Posted: 11/4/2015 9:52:49 AM EDT
[#33]
I may try and take the bolt apart and clean it up and see how it does. Will look into the gas block and see what I can get.. The saga continues, I think I will stick to AR 15's...
Link Posted: 11/4/2015 12:05:25 PM EDT
[#34]
Discussion ForumsJump to Quoted PostQuote History
Quoted:
I may try and take the bolt apart and clean it up and see how it does. Will look into the gas block and see what I can get.. The saga continues, I think I will stick to AR 15's...
View Quote

The 10s are a little more work to get working right but once I dialed down the gas I absolutely love shooting mine. They are definitely worth it.
Close Join Our Mail List to Stay Up To Date! Win a FREE Membership!

Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. One new winner* is announced every week!

You will receive an email every Friday morning featuring the latest chatter from the hottest topics, breaking news surrounding legislation, as well as exclusive deals only available to ARFCOM email subscribers.


By signing up you agree to our User Agreement. *Must have a registered ARFCOM account to win.
Top Top