Gibbz g10 308 build problems

[Franklin0722]

I have built a lr308 and having major feed problems. The magazine will hold the bolt open but will fail to load a round. The bullets will be scratched and sometimes even bent. The parts used in the build are

1. Gibbz arms g10 upper reciver. 2. Palmetto state lower. 3. Ballistic advantage ss fluted barrel.4. Aero precision nickle bolt carrier group.5. Oden adjustable gas block. 6. Cmc 2.5 trigger.

I have taken the gun to my local gun smith and has left everyone scratching there heads. We know it is something to do with the upper because a different upper on the PA lower will work correctly. Any help would be much appreciated. Paid so much money for a gun that is nothing more than a single shot at the moment just really want it to work correctly. 

 

Edited January 18, 2020 by Franklin0722

[washguy]

Franklin......so you took all the stuff to a gunsmith and he couldnt find the problem...right?....and now you make a post "The magazine will hold the bolt open but will fail to load a round "  this will hardly help us out here....we need pics and or a vid and more info than what you posted.....looks to me like you need to keep the barrel  and the bcg...and throw the rest of the crap away    Wash

Why would you pay so much money for that non working crap?

Edited January 18, 2020 by washguy

[98Z5V]

This is the FOURTH confirmed problem we've seen with the Gibbz platform here.  This is #4.

Here is the Gibbz history here.  There have been no resolutions or fixes found, as far as I know.

https://forum.308ar.com/search/?q=Gibbz

Edited January 19, 2020 by 98Z5V

[Ravenworks]

38 minutes ago, 98Z5V said:

This is the FOURTH confirmed problem we've seen with the Gibbz platform here.  This is #4.

Here is the Gibbz history here.  There have been no resolutions or fixes found, as far as I know.

https://forum.308ar.com/search/?q=Gibbz

They sure are proud of their receivers.

I did see this while I was at their site,have no idea if it's applicable.

IMPORTANT!! You MUST use the G10 Enhanced Cam Pin in the G10 Side Charging Uppers!
Use of a Standard Cam Pin will cause the Bolt Carrier Group to lock up in the G10 Upper Receiver and be VERY difficult to remove and could damage the Upper Receiver.

https://gibbzarms.com/product/g10-308-side-charging-upper-receiver-right-handed/

 

[Franklin0722]

May have found a fix. Did some sanding on a pmag along with some tape and I can actually get it to cycle the ammo. I had to file down where the mag would go just a little deeper into the receiver. I will try and take it to my range this week and see if it will actually shoot. I'm also going to order a metal magazine. Went to every chain and small gun store no one cares them. However every part on this build said that it is compatible with pmags. The lower itself will work with pmags using a different upper. 

Edited January 19, 2020 by Franklin0722

[98Z5V]

50 minutes ago, Franklin0722 said:

 I had to file down where the mag would go just a little deeper into the receiver. 

The lower itself will work with pmags using a different upper. 

That right there tells you that it's the upper receiver that's out of spec - not the PMag. 

[Albroswift]

I have 3 or 4 of the C products steel mags for 308 and they fit a little looser then the Magpuls, function quite well in a couple different builds. 

[Franklin0722]

On 1/19/2020 at 10:19 AM, Albroswift said:

I have 3 or 4 of the C products steel mags for 308 and they fit a little looser then the Magpuls, function quite well in a couple different builds. 

Ordered a c product steel mag to see if that will work. 

[COBrien]

The problem I had was headspacing. The bolt -- naked -- would headspace just fine on my Criterion barrel. But put that bolt in a carrier, and the assembly would not close on any headspace gauge or a live round. Sent the upper off to Criterion, and they said the headspace was in-spec, and actually a bit looser than they prefer for precision builds. They narrowed it down to the upper receiver (because, after all, there are only so many things that can cause a headspace problem...).

I called Gibbz Arms and they offered to look it over. For a price. No thanks.

So now the upper is just sitting, stripped, in a drawer in my workbench, waiting for me to get the time, energy, and want-to to un-fvck it.

Edited January 21, 2020 by COBrien

[Franklin0722]

I just received my C products steel mag and no solution. The steel mag will not hold the bolt open while the p mag would. With the p mag I can push up on it really hard and the bullets will load normal. With the metal mag if I pushed up on the the bullet would load but the bolt would not go into battery all the way. I tried to call gibbz arms they are closed this week for shot show. Either they can fix it l, send me a new one or just return the damn thing.  

[RedRiverII]

I read somewhere recently to use STANAG mags exclusively in a certain product.  Perhaps a PTR or something.  Don't remember,  or file that rib off of the pmag.

[Albroswift]

On 1/23/2020 at 3:25 PM, Franklin0722 said:

I just received my C products steel mag and no solution. The steel mag will not hold the bolt open while the p mag would. With the p mag I can push up on it really hard and the bullets will load normal. With the metal mag if I pushed up on the the bullet would load but the bolt would not go into battery all the way. I tried to call gibbz arms they are closed this week for shot show. Either they can fix it l, send me a new one or just return the damn thing.  

Friend just finished a 6.5 build, no mags yet borrowing some of my steel mags so if you want to sell them let me know. He hasn't ordered any yet. 

[unforgiven]

On 1/21/2020 at 10:56 AM, COBrien said:

The problem I had was headspacing. The bolt -- naked -- would headspace just fine on my Criterion barrel. But put that bolt in a carrier, and the assembly would not close on any headspace gauge or a live round. Sent the upper off to Criterion, and they said the headspace was in-spec, and actually a bit looser than they prefer for precision builds. They narrowed it down to the upper receiver (because, after all, there are only so many things that can cause a headspace problem...).

I called Gibbz Arms and they offered to look it over. For a price. No thanks.

So now the upper is just sitting, stripped, in a drawer in my workbench, waiting for me to get the time, energy, and want-to to un-fvck it.

That suks

[98Z5V]

On 1/23/2020 at 4:25 PM, Franklin0722 said:

I just received my C products steel mag and no solution. The steel mag will not hold the bolt open while the p mag would. With the p mag I can push up on it really hard and the bullets will load normal. With the metal mag if I pushed up on the the bullet would load but the bolt would not go into battery all the way. I tried to call gibbz arms they are closed this week for shot show. Either they can fix it l, send me a new one or just return the damn thing.  

Loaded mag or empty mag?  Sorry, I just caught this one. If you didn't already, try this test with empty mags.  Just put an empty mag in, charge it, and see if it holds the BCG locked to the rear.  No ammo in the mag.

[Franklin0722]

Will not load ammo on a loaded mag and wont hold the bolt open on empty. I called gibbz they offered to take a look at it for free and would replace the part if needed and if not I could get a refund. 

[98Z5V]

7 minutes ago, Franklin0722 said:

Will not load ammo on a loaded mag and wont hold the bolt open on empty. I called gibbz they offered to take a look at it for free and would replace the part if needed and if not I could get a refund. 

Does the mag lock securely in the lower - won't fall out?  Also, what brand is the lower?  Sorry if you stated that already, and I missed it.

EDIT - Damn, PSA lower.  Know if it's one of the first ones, or a Gen 2? Or even that Gen 3 that's out now?...

Edited January 30, 2020 by 98Z5V

[2ndAmendMedic]

I had a similar issue with Gibbz G10 upper receiver. The upper was disengaging the bolt catch. A bit of modifying the bolt catch and it cleared it up. It was the cheapest part so I figured why not start there. It seems that their uppers are out of spec. or aren’t designed to work well with non-Gibbz lowers. It’s a shame, I really like a side charging semi-auto upper in .308. Makes me hesitant to purchase their MG4 for an upcoming project I had in mind.

[98Z5V]

27 minutes ago, 2ndAmendMedic said:

I had a similar issue with Gibbz G10 upper receiver. The upper was disengaging the bolt catch. A bit of modifying the bolt catch and it cleared it up. It was the cheapest part so I figured why not start there. It seems that their uppers are out of spec. or aren’t designed to work well with non-Gibbz lowers. It’s a shame, I really like a side charging semi-auto upper in .308. Makes me hesitant to purchase their MG4 for an upcoming project I had in mind.

Your info, and your mods, would probably benefit all the Gibbz owners here, so pics of what you did would greatly help, both now and in the long run.

[2ndAmendMedic]

37 minutes ago, 98Z5V said:

Your info, and your mods, would probably benefit all the Gibbz owners here, so pics of what you did would greatly help, both now and in the long run.

I’ll see what I can do. I should be able to snap some pictures tomorrow.

[2ndAmendMedic]

I’m no gunsmith nor am I pretending to be one. But this seemed to remedy the situation for me. My bolt catch works better now, but it’s on a “hair trigger.” As in, if I give it a smack anywhere on the rifle the bolt rides forward. It locks to the rear on empty mag and it cycles fine.

specs are

Gibbz G10 upper, Shillen match barrel and bolt, NiB BCG. 80% Arms lower, CMMG lpk, Geissele SSA-E trigger. The rifle shoots about as good as I can; I’m still quite a novice at LRS. I’m working a few other things out on the rifle, but I’ve enjoyed it so far.

I hope this helps or maybe I’m wrong?

 

[Ravenworks]

1 hour ago, 2ndAmendMedic said:

My bolt catch works better now, but it’s on a “hair trigger.” As in, if I give it a smack anywhere on the rifle the bolt rides forward.

That's a really dangerous situation, your bolt catch is not working better.

If the bolt catch is what's causing your gun to fire anytime it wants to with a bump the cause needs to be found ASSP and fixed.

[98Z5V]

2AMedic - we need a description of what you did to the bolt catch - the pics don't really spell it all out. 

[2ndAmendMedic]

19 hours ago, Ravenworks said:

That's a really dangerous situation, your bolt catch is not working better.

If the bolt catch is what's causing your gun to fire anytime it wants to with a bump the cause needs to be found ASSP and fixed.

It doesn’t slam fire, that’d be fun, but quite scary... What I meant is a good bump will make it disengage off the bolt catch. The bolt wouldn’t catch previously, now it does. The upper receiver made contact with part of the bolt catch and kept it from engaging properly, now it engages, but barely. The slipperiness may be due to the NiB coating on the bolt?

17 hours ago, 98Z5V said:

2AMedic - we need a description of what you did to the bolt catch - the pics don't really spell it all out. 

I noticed that the upper receiver was making contact with the bolt catch and would not allow the bolt catch to properly engage and it would not hold the bolt open on last round or even when manually locking it to the rear. I cut down the area of the bolt catch that was making contact with the UR. Area in blue triangle in the pic was cut. It seems to work okay for now. It could be that I got the wrong spec bolt catch? I used a CMMG .308AR LPK so it should’ve been GtG.

I haven’t had much range time recently to mess with it further as I just had another kid. Family takes precedence.

[Franklin0722]

Sorry to take so long to reply. With quarantine everything has been moving slow. So I sent my g10 upper and my gen 3 psa lower to gibbz. After testing they said that the psa gen 3 was not compatible. So they talked me into buying the g10 lower along with taking my lower apart and switching it over to me. They also said that they would test it and made sure it worked. I just now got around to being able to shoot it... The damn thing still does the thing. Tried 4 different mags all the same. 1st bullet loads no problem. Shoot it and you see it eject and the bolt close in full battery as if there is a bullet in the chamber. Pull the trigger nothing. It will not load 2 bullets in a row its failure to feed just about every time. So now I'm waiting to get back in touch with gibbz arms. Im a little aggravated at the whole process of this rifle build. 

Edited May 26, 2020 by Franklin0722

[Chuck Plissken]

Random thought. From your last post/update and description I felt the need to chim in. What your last post describes to me is not a mag problem if it loaded a new round. I had a bad disconnecter in a lower parts kit a while back. It wouldn't let the trigger hold and reset itself but would do just what your saying. A round was chambered but trigger was already released due to not resetting.  I had a single shot rifle and that's what I found. Swapped the disconnecter out with another one at home and boom! It worked.

Edited May 28, 2020 by Chuck Plissken