New 9mm Bolt with integrated gas key

[Aircooled6racer]

Hello: No problem if you or anyone else wants to use the forward assist on a blowback or regular AR that is fine. It is your choice to do so. I still think the one piece bolt is a great idea though. Less parts, less chance of failure. Thanks, Eric

[robertg5322]

Am I missing something? Why are gas keys shearing when there's no gas acting against them?

 

Please correct me if I'm mistaken, but the only time the gas key (why is it called that on these non-gas operated things?) is in any way being worked is when initially chambering a round or clearing a jam, right? Is this when they're failing? Inertia from riding the BCG back and forth?

 

If this is true (and it may very well not be), it would seem manufacturers are using junk bolts to fasten them to the BCG? Replacing the bolts with higher-grade units; would seem like a logical solution. 

 

Has anyone had replacement bolts of known higher grade failing?

 

Thanks for the info.

[vinconco]

9 minutes ago, robertg5322 said:

Am I missing something? Why are gas keys shearing when there's no gas acting against them?

 

Please correct me if I'm mistaken, but the only time the gas key (why is it called that on these non-gas operated things?) is in any way being worked is when initially chambering a round or clearing a jam, right? Is this when they're failing? Inertia from riding the BCG back and forth?

 

If this is true (and it may very well not be), it would seem manufacturers are using junk bolts to fasten them to the BCG? Replacing the bolts with higher-grade units; would seem like a logical solution. 

 

Has anyone had replacement bolts of known higher grade failing?

 

Thanks for the info.

I noticed my NFA BCG had a loose gas key..... probably just before it sheared.   I put it back on with some red Loctite and contacted NFA about it.   They wrote back that they don't recommend Loctite but it probably would work and that I could send it back for "repair".   I then asked if the "repair" would involve properly staking the cap screws and then..........crickets. 

[Aircooled6racer]

1 hour ago, robertg5322 said:

Am I missing something? Why are gas keys shearing when there's no gas acting against them?

 

Please correct me if I'm mistaken, but the only time the gas key (why is it called that on these non-gas operated things?) is in any way being worked is when initially chambering a round or clearing a jam, right? Is this when they're failing? Inertia from riding the BCG back and forth?

 

If this is true (and it may very well not be), it would seem manufacturers are using junk bolts to fasten them to the BCG? Replacing the bolts with higher-grade units; would seem like a logical solution. 

 

Has anyone had replacement bolts of known higher grade failing?

 

Thanks for the info.

Hello: I think the sheared bolt maybe one of two things. Over torqueing the bolts or poor quality bolts. The pounding action would be the only force on the bolts. Red Loctite would solve the coming loose problem if that is the problem. We used to use that on stripper bolts on stamping dies for production runs. Tool and Die talk for we don't want the damn things coming loose. I would bet it is poor quality bolts. Thanks, Eric

[L3324temp]

A 223 bolt carrier closes far more gently compared to a 9mm bolt. Between the bolt engaging the locking lugs and the longer bottle neck cartridge it gradually slows down at the end rather than slamming.

 

The weight of the gas key is stressing the bolts from the rapid slam on closing.

 

Sent from my iPhone using Tapatalk

 

 

[amp]

On 3/3/2017 at 8:06 AM, Aircooled6racer said:

Hello: I agree about getting the right parts to do the job correctly the first time. I am not sure why the bolt on the gas key are breaking for you guys. Could be poor quality bolt or over torquing them? Maybe buy some good grade bolts and torque them to specs. I have been running the KVP bolt and a JP bolt with no problems after 1000-1500 on each. The one piece bolt seems like a great idea to solve this problem. Thanks, Eric

FYI, i have now sheared 2 keys on my KVP bolt. appx 700-800 rounds total.

both showed signs of stretching, ie over torqued

But they were also cheap cap screws. I have some higher quality ones on order now.

 

 

Edited March 6, 2017 by amp

[Flatland Shooter]

So far I've not sheared the gas key bolts on either of my 9mm bolts, but if PSA and Spinta did overtorque the original screws or they used cheap cap screws, replacing them with good quality ones sounds like a good idea.

 

Can anyone verify regular gas key bolts for .223 will fit the 9mm bolts?

 

Thanks.

 

Bill

[amp]

29 minutes ago, Flatland Shooter said:

So far I've not sheared the gas key bolts on either of my 9mm bolts, but if PSA and Spinta did overtorque the original screws or they used cheap cap screws, replacing them with good quality ones sounds like a good idea.

 

Can anyone verify regular gas key bolts for .223 will fit the 9mm bolts?

 

Thanks.

 

Bill

 

8-32 x 1/4 on my Kaw Valley

 

[1911luvr]

So far I've not sheared the gas key bolts on either of my 9mm bolts, but if PSA and Spinta did overtorque the original screws or they used cheap cap screws, replacing them with good quality ones sounds like a good idea.
 
Can anyone verify regular gas key bolts for .223 will fit the 9mm bolts?
 
Thanks.
 
Bill

The are the same. The sheared bolts on my ATI were exactly the same as the grade 8 bolts I ordered only for a standard 5.56 BCG.


Sent from my iPhone using Tapatalk

[robertg5322]

50 minutes ago, 1911luvr said:

The are the same. The sheared bolts on my ATI were exactly the same as the grade 8 bolts I ordered only for a standard 5.56 BCG.


Sent from my iPhone using Tapatalk

You wouldn't know the size and length off the top of your head, would you?

[amp]

11 hours ago, robertg5322 said:

You wouldn't know the size and length off the top of your head, would you?

8-32 x 1/4

[Skeeter190]

Does anyone know if this is an issue on the JP bcg also?

[robertg5322]

8 hours ago, amp said:

8-32 x 1/4

Thanks.

[Aircooled6racer]

1 hour ago, Skeeter190 said:

Does anyone know if this is an issue on the JP bcg also?

Hello: I have over 1000 rounds through my JP bolt with no problem. I also have over 1000 rounds through my Matrix bolt as well. I think we have all have come to the conclusion it is bad bolts. I have a KVP bolt coming for another ultra light build so I will see how it holds up. Thanks, Eric

[Solvability]

Has anyone seen an Ar9 with a catastrophic disassembly?  I have seen a number in which the cases failed but it caused no real damage.

[robertg5322]

Checked the gas key on the bolt in my ATI carbine and it was loose. Took about 1/8th of a turn. It was staked, and I re-staked it after tightening the replacement bolts which were also secured with red Lock titer. 

 

Overkill? Maybe, but that'should how I roll. We'll  see...

[rishii]

On 3/1/2017 at 10:37 AM, 1911luvr said:

Faxon just released an integrated BCG that solves the problem of sheared gas keys. I've experience a gas key shearing failure once already in less than 4k rounds, so I'm eyeing this intently.

$165

 
http://faxonfirearms.com/faxon-9mm-pcc-blowback-full-mass-bolt-carrier-group-complete-nitride//
 [/url'>
[url=] 
 

Dvor.com has them on sale for $134

you have to join to see the price

[bwframe]

Just discovered my KVP bolt had sloppy loose gas key screws. 1st indicator was a fairly stiff dragging when removing the bolt from the NFA billet upper. I had wiped it down prior to the Monday match and it seemed fine, although I didn't really pay much attention to the gas key. 

 

The bolt was slightly beat up in front of the gas key, where the side charging handle lug mates with it I believe. I smoothed out the slight burr that had formed there with a file. It looks as if the burr was dragging in the upper on the edge of the gas key channel. 

 

I red-loctited the screws, torqued them as much as felt comfortable and attempted restaking. We'll see how it goes. May not get to try it before the Sunday match. 

[usmc1094]

https://visiondefensellc.com/product/9mm-bolt-carrier-group/  I got one from here.  They are made by battle rifle development.  If you order from battle rifle development the have a few different finishes.