New AR Build, Help Needed!

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donebymonday

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Hi all! Long time lurker, first time poster...

I just finished my first build which I was super excited for. I haven't shot it yet though, because I am running into problems. It was suggested I rack a mag of rounds through to make sure it's working well. And, I am glad I did! This is what happens after it ejects six or seven-ish rounds. It gets caught up, then I clear it, and after a few more, repeats. Once I even picked up a round and found it compressed... eek!

The rounds that do eject come out strong, so I can't figure out the rhyme or reason here. First build stump town!

Any suggestions on how I fix this?

Thank you in advance!!

PXL-20210716-175356964.jpg

PXL-20210716-175405379.jpg

PXL-20210716-223222298.jpg
 
The angle of the mag lips also look a little high in front, are you sure the mag was seated completely?
 
Have you tried racking the rounds slowly to see if you can pinpoint where they are hanging up?

Have you tried a different magazine? I had a build that was giving me grief until I figured out that the magazine I was using was just ever so slightly out of whack that it directed the rounds just beneath the start of the feed ramp. A magazine change made my AR work perfectly.
 
BTW, congrats on your first post and welcome to THR.
There are others here who are more expert on the Ar than me and will probably join in, but I do own one or five and have never had a round compressed that far. A new tight mag that isn't really seated all the way can cause that, I give mine a good slap to make sure and they also seat easier if the bolt is open.
 
Start with a different mag. Seat the mag correctly; push up till you hear a 'click', then pull down to be sure it locked in. Then repeat the same test you are using. If it still happens, it's in the gun; If not, retry the mag you first used. This sounds like instructions for a suppository, but insert as directed, and test again. If it does not happen, it was in the way you were inserting it. If it does happen, label that mag for use only by people you dislike, and get another one.
Be sure you are charging it correctly. Don't ride the charging handle forward; let go at the rear and let the recoil spring do it's job.

AK Hunter said:
Shoot it! It’s the only way you will know for sure if you have a problem.
Click to expand...

It would be wise to be sure the rifle passes a function test before firing it. o_O
 
You said YOUR first build, so you built it right? Did you build the upper also or did you buy it built?

If you built everything, did you check all the specs with go/no-go gauges? Specifically the barrel to be sure you don't have issues like this.

Give us some more info and I'm sure we can help you out. Do not fire the rifle until you're sure it's safe. If you have to, take it to a smith to have it checked out.
 
Welcome Aboard @donebymonday!
Whose lower part kit was it?
Is the magazine catch pristine? Looks like the magazine is a little low, but it’s hard to tell from here.
Is the magazine clean?
Are the rounds grit free?
Seven is just about how many are straight before the curve in the magazine, if it doesn’t feed it’s usually the magazine…
 
What ammo is that ? ( You don't want one to fire like the bullet setback shown. )

Pics of the magazine feed lips... your photos make the feed lips look odd to me.
 
Mk-211 said:
You said YOUR first build, so you built it right? Did you build the upper also or did you buy it built?

If you built everything, did you check all the specs with go/no-go gauges? Specifically the barrel to be sure you don't have issues like this.

Give us some more info and I'm sure we can help you out. Do not fire the rifle until you're sure it's safe. If you have to, take it to a smith to have it checked out.
Click to expand...

Hello!

I guess "build" may have been a little premature... I put it together though :)

I have an Anderson multi-cal lower which I paired with this Palmetto kit: https://palmettostatearmory.com/psa...-5-lightweight-m-lok-classic-rifle-kit10.html

I have tried both Magpul and Amend2 magazines, both present with the problem.

I have tried with magazines loaded with American Eagle and Speer.
 
You can't properly test the rifle manually cycling it. Take out and shoot it.
Starting out I would make sure it's lubricated and bring extra mags.
Post pictures of any failures and go from there.
 
On new parts, it usually helps to cycle the action several times without ammo (like 25 times or so) with proper lube.
That seems to seat in the locking lugs so the bolt runs smoother. Otherwise, I've had the first 2 or 3 rounds fail to cycle the bolt fully.
As above - seat those mags fully - easier to seat with the bolt locked back.
 
carbine85 said:
You can't properly test the rifle manually cycling it. Take out and shoot it.
Starting out I would make sure it's lubricated and bring extra mags.
Post pictures of any failures and go from there.
Click to expand...

I beg to differ. A manual function test should always be performed before firing any gun after building, or repair. If it passes the manual function test, then a test fire is warranted. They do not leave the shop until they pass a manual function test.
This is what the US Army Armorer school taught me, and every gun shop I smithed for insisted on the same procedure.
 
Hi all! Here are some more photos, in case these help. These include photos of a magazine seated with the bolt locked back, then when I send the bolt forward what happens (looks like the round isn't seated high enough to catch properly?? But it's as high as it will go and locked in solid.) Then a photo of the mags I have tried to show the feed lips, which I think look ok?

Forward.jpg
mags.jpg
Seated.jpg

Thanks again for all the feedback!!
 
Get rid of the 'jungle clip holder'.
If you insist one something like that,
https://www.midwayusa.com/promotion?targetLocation=/_/N-18830+4294926540?Np=2&Ntpc=1&Ntpr=1&Nrpp=24&Nr=AND(p_visible:1,customertypeid:1)&Ns=p_metric_sales_velocity|1&UserSearchQuery=GUN+MOUNTED+MAG+HOLDER&userSearchQueryRemoveAction=&hasFiltersApplied=True

From the top picture it is obvious your magazine is not sitting high enough. The mag coupler is probably doing it, but if it isn't, and you are seating them correctly, hie thee to the smithy!
Have you tried locking the bolt back, inserting the mag, then hitting the bolt release? Or have you been inserting the mag with the action closed, then charging and releasing the charging handle when it is fully back?

Feed lips look OK from that angle; If you pull the upper and take a pic through the back of the upper, it will show them better.
 
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I am with entropy, you want to know the rifle isn’t mangling the ammo before you shoot it. If you have setback like you posted in the OP and fire that round, you could be posting a kaboom thread next.

Don’t baby the thing though, once you have the charging handle all the way back, let your fingers slip off from the rearward force, think sling shot, do not hold on to it “riding” it back home. Alternatively, just lock the BCG open, insert Mag and hit the release.

I can’t see enough detail from your photo, what one of these looks most like what you have?

36CEFC99-0F6D-48DC-AA18-0A60CC012FF9.jpeg

While you have it opened up measure from the top of the lower to the top of the feed lips of your Magpul magazine, like this and let us know the height.

BD09A521-A524-48FE-8D06-656D1B23D6E3.jpeg
 
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entropy said:
I beg to differ. A manual function test should always be performed before firing any gun after building, or repair. If it passes the manual function test, then a test fire is warranted. They do not leave the shop until they pass a manual function test.
This is what the US Army Armorer school taught me, and every gun shop I smithed for insisted on the same procedure.
Click to expand...
I said "Properly Tested" meaning full function. Regardless of you military training it's not properly tested until live ammo is cycled through it
 
donebymonday said:
Hi all! Here are some more photos, in case these help. These include photos of a magazine seated with the bolt locked back, then when I send the bolt forward what happens (looks like the round isn't seated high enough to catch properly?? But it's as high as it will go and locked in solid.) Then a photo of the mags I have tried to show the feed lips, which I think look ok?

View attachment 1012162
View attachment 1012163
View attachment 1012164

Thanks again for all the feedback!!
Click to expand...
That last photo seems to look like maybe the barrel is not "clocked" to the lower correctly (refer @jmorris 's photos).
So, the bolt may be mashing the rounds into the blunt end of the barrel, rather than a ramp to pop them into the chamber.

What buffer is in this build? This last as I'm wondering about bolt speed as well as round presentation here.
 
Check to see if the rear corner of the barrel extension is overhanging the receiver feed area. Your last picture seems to show this exactly. I've seen several rifles that do this. Best cure is to get a good barrel, and check the fit before its finally installed. If you want to clear up this area yourself, a file will not work. This calls for careful work with a rotary grinding tool.
 
A couple of quick notes:

Magpul mags have anti-tilt followers installed as standard; assuming it’s a new magazine, it isn’t the follower. Could be feed lips on a bad batch but it’s giving other mags the same hassle.

All PSA uppers come with M4 feed ramps so unless alignment is an issue, that isn’t your problem either.

Magazine coupler is not present on all mags so while it may present its own issues, it cannot affect the others. Still agree with ditching it.

Almost, and that word is key, almost safe to eliminate those three.

I would start with the unanswered sling shot or riding the CH question. Then get it properly lubed, inspect the bolt face, and swap the magazine catch. If you don’t have a second catch, PM me and I’ll send one out free of charge.
 
Skylerbone said:
A couple of quick notes:

Magpul mags have anti-tilt followers installed as standard; assuming it’s a new magazine, it isn’t the follower. Could be feed lips on a bad batch but it’s giving other mags the same hassle.

All PSA uppers come with M4 feed ramps so unless alignment is an issue, that isn’t your problem either.

Magazine coupler is not present on all mags so while it may present its own issues, it cannot affect the others. Still agree with ditching it.

Almost, and that word is key, almost safe to eliminate those three.

I would start with the unanswered sling shot or riding the CH question. Then get it properly lubed, inspect the bolt face, and swap the magazine catch. If you don’t have a second catch, PM me and I’ll send one out free of charge.
Click to expand...

Hello all! When I get home this evening I will take some photos and measurements and post some more on those questions - thank you all for the ideas! I also have an older PSA build I will be able to take the upper from and see what happens there. I hadn't thought to try that before.

On the note of magazines, I will get rid of the coupler. For this problem though, I have now tried ten separate magazines of all kinds... amend2, magpul, D&H... and all present the problem.

As far as the charging of the round, I have tried locking back the bolt, inserting a magazine, and releasing forward, and it still does it. I also make sure I pull back the charging handle and release when it's as far back as it goes, to be sure I am not riding it forward. I haven't held on to the handle as it goes forward at all.

As far as the magazine catch, could this problem occur by me turning the release too much or too little? I'm not sure that I am referencing it correctly. But the magazine release, where you push it in with a punch and then turn the opposite side bar. The video I watched to build said make sure the screw was flush with the face of the release, which I did, but the magazine sometimes didn't fall when I pushed it that way, so I brought it back one more turn and it seemed to work right after that. But maybe that is a problem?
 
donebymonday said:
As far as the magazine catch, could this problem occur by me turning the release too much or too little? I'm not sure that I am referencing it correctly. But the magazine release, where you push it in with a punch and then turn the opposite side bar. The video I watched to build said make sure the screw was flush with the face of the release, which I did, but the magazine sometimes didn't fall when I pushed it that way, so I brought it back one more turn and it seemed to work right after that. But maybe that is a problem?
Click to expand...

If the lower is machined correctly (pocket depth) then the number of twists won’t matter when it comes to positioning the magazine though it can affect release if you cannot depress the button far enough to allow the magazine to release.

What I’m meaning by the catch being problematic is not being formed correctly. Again, a very outside chance but if the pad is too narrow it might allow the magazine to slip and sit a bit low. Pictures for posterity’s sake.


This is the pad that catches the magazine and holds it.
3AB768F4-1554-4514-87F8-69ACC885F6CC.jpeg

What things look like without the receiver blocking the view.
735FD2E8-3BA6-4F7D-B9B2-FDB020BC8CB5.jpeg


5F8A6872-C406-4EC8-91CF-904E82878E15.jpeg


B32CEE1A-C836-462A-914D-20AFFDE0F418.jpeg
 
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