Gas Key - Bolts Sheared Off

[BillChunn]

It appears that this is getting to be a common occurrence.   The bolt was used in a CKArms carbine that was part of the initial buy on "Black Friday" in November of '17.  It arrived just before Christmas and has about 4,000 rounds through it.  Yesterday at practice the gas key broke away from the bolt carrier and jammed the rifle.  Both bolts are sheared off.  

 

Does anyone know the cause of this failure?  Is it a bad batch of bolts or just a bad design that has been carried over from the AR15?  Has anyone come up with a one piece design that is not outrageously priced? 

 

The good news is that it happened at practice and not at the Area 6 match next weekend, 1,500 miles from home.  Am in the process of getting it replaced before the match.  Will be driving south down I-75 so a slight detour will be incorporated to go by CKArms and see if a replacement is available.

 

BC

 

 

[bmiller]

Bill, my PSA bolt did that when I first bought it.  I think the barrel could be head spaced a little deep. Are there any marks on the barrel or bolt where they are coming into contact?   I think the chamber being too deep allows the bolt to smash into the back of the barrel causing the bolts to shear.  I pulled my barrel and faced it off to change the head space, the problem went away.  Since I have switched to a faxon gen 2 bolt.  It uses a one piece body with an Ar extractor.  There are a bunch of people marketing that bolt design that are rebranded.  The best deal I found was at AIM Surplus. $129 if I remember correctly.

[longbeard]

It's a regular occurrence on the AR9 platform.  Possibly caused by too light of a buffer spring setup or too hot of a load, but most likely from cheap craftsmanship.  I would steer you towards the Taccom bolts for PCC.  Get the upgraded gas key

[Flatland Shooter]

I think there is a possibility that some of those gas key bolts are not properly staked.  I routinely check to see if they are tight when I clean the gun.  On one PSA bolt the bolts were coming loose at around 6000 rds.   Replaced and restaked and put another 4000 rds through the gun without problems.

 

I suppose I could have just tightened the bolts but felt it was prudent to go ahead an replace with new ones.

[longbeard]

I think there is a possibility that some of those gas key bolts are not properly staked.  I routinely check to see if they are tight when I clean the gun.  On one PSA bolt the bolts were coming loose at around 6000 rds.   Replaced and restaked and put another 4000 rds through the gun without problems.
 
I suppose I could have just tightened the bolts but felt it was prudent to go ahead an replace with new ones.

This.
And cheap screws.

Sent from my SM-N950U using Tapatalk

[nickbfishn]

Where’s the best place to buy food replacement bolts?

[Flatland Shooter]

9 hours ago, nickbfishn said:

Where’s the best place to buy food replacement bolts?

 

I buy them from Brownells.

 

https://www.brownells.com/rifle-parts/bolt-parts/bolt-carrier-parts/bolt-carrier-hardware/ar-15-m16-bolt-carrier-key-screw-prod17529.aspx

[Darqusoull13]

9 hours ago, nickbfishn said:

Where’s the best place to buy food replacement bolts?

I'd pick up a JP bolt. I'm right around 31,000 rounds one and ~33,000 rounds on the other. Both still rock solid. Let me know if you need any help with your selections 

[photoracer]

I lost 2 gas keys from my first 2 9mm BCGs. I firmly believe its mainly due to improperly stakes bolts as in the first one I found the bolts were loose the night before a big SC match and sure enough they sheared off and I had to borrow a friends PCC to shoot the last stage. I have since opted for a higher quality 9mm BCG, one from Faxon, that uses a flat faced gas key instead of a sloped one. There is at least one maker out there that has the gas key machined out of the entire BCG so no bolts to break.

[TRUBL]

 You are shearing those bolts because the 'gas key' is too heavy. Don't matter if it is staked, loctitied, really tightened or even if it is a JP bolt.......they are going to eventually work loose and shear off. How to fix that???? Make them lighter......take them off get them on a mill or hand grinder and cut the crap out of them. make them lighter. Look at my extreme bolt on the taccom website and let that be your guide.....oh.....we've NEVER sheared our off....EVER. Wonder why?

[dmshozer1]

1 hour ago, TRUBL said:

 You are shearing those bolts because the 'gas key' is too heavy. Don't matter if it is staked, loctitied, really tightened or even if it is a JP bolt.......they are going to eventually work loose and shear off. How to fix that???? Make them lighter......take them off get them on a mill or hand grinder and cut the crap out of them. make them lighter. Look at my extreme bolt on the taccom website and let that be your guide.....oh.....we've NEVER sheared our off....EVER. Wonder why?

Tim,

Just asking but how can you cut a lot off the gas key when that is what rides inside the charging handle to keep the bolt up right.

Or am I missing something?

[Flatland Shooter]

14 minutes ago, dmshozer1 said:

Tim,

Just asking but how can you cut a lot off the gas key when that is what rides inside the charging handle to keep the bolt up right.

Or am I missing something?

 

Not sure but I think Tim is saying to take off the gas key to grind it down, then when much lighter bolt and stake it back on.

 

Maybe that could be the next Taccom product.  A super lightweight gas key.

Edited April 10, 2018 by Flatland Shooter

[TRUBL]

11 hours ago, Flatland Shooter said:

 

Not sure but I think Tim is saying to take off the gas key to grind it down, then when much lighter bolt and stake it back on.

 

Maybe that could be the next Taccom product.  A super lightweight gas key.

We already offer that

[TRUBL]

11 hours ago, dmshozer1 said:

Tim,

Just asking but how can you cut a lot off the gas key when that is what rides inside the charging handle to keep the bolt up right.

Or am I missing something?

You did't look at our bolt or our orientation key, do that and answer your own question.......and for the record.....9mm bolts do not have gas keys......get that out of your fricken heads!!! This is why we get the monkey see, monkey do crap. A correctly made bolt engages the charge handle.......not the key........no argument, if you do, you are an idiot

[L9X25]

56 minutes ago, TRUBL said:

You did't look at our bolt or our orientation key, do that and answer your own question.......and for the record.....9mm bolts do not have gas keys......get that out of your fricken heads!!! This is why we get the monkey see, monkey do crap. A correctly made bolt engages the charge handle.......not the key........no argument, if you do, you are an idiot

 

Come on Tim, get off the fence and tell us how you really feel!  

[Sarge]

19 minutes ago, L9X25 said:

 

Come on Tim, get off the fence and tell us how you really feel!  

Yeah, potential future customers are always watching.

[dmshozer1]

1 hour ago, TRUBL said:

You did't look at our bolt or our orientation key, do that and answer your own question.......and for the record.....9mm bolts do not have gas keys......get that out of your fricken heads!!! This is why we get the monkey see, monkey do crap. A correctly made bolt engages the charge handle.......not the key........no argument, if you do, you are an idiot

Dear Tim,

I asked a simple question.

I did look at your extream bolt. I also looked at your normal "key" that states it is lighter. Looks like any  other "key" I have ever seen on a 9mm bolt.

Your products are good. Your attitude is bad!

All respect I ever had for you just went out of the window!

[Sarge]

41 minutes ago, dmshozer1 said:

Dear Tim,

I asked a simple question.

I did look at your extream bolt. I also looked at your normal "key" that states it is lighter. Looks like any  other "key" I have ever seen on a 9mm bolt.

Your products are good. Your attitude is bad!

All respect I ever had for you just went out of the window!

?

[TRUBL]

I'm just a cranky old bastard.....tell you like it is. You complain about crap breaking and have no clue why is does.....NO ONE in the industry will tell you why or how to fix it.....just give them more money for the next thing. I lay it all out......I tell you truth, I am blunt, crass and basically really don't about having anyone respect for me, my products prove it.......if you can't live with that.....great, buy crap that breaks, and complain about it on the forums. I will tell you the truth......probably not what you want to hear, but it is the truth. Did you want me to sugar coat it? So you don;t feel offended? or can ya say......somgun.....the old bastard is right!! I'm gonna follow his lead. Oh, and BTW....you're welcome 

 

OH.....our key don't look anything like anyone elses......look again

 

Edited April 10, 2018 by TRUBL

[CHA-LEE]

A better solution is to simply have the "Gas Key" welded to the bolt carrier. When the bolts sheared off on my test AR9 we replaced the bolts, staked AND TIG welded the gas key to the bolt carrier. That thing isn't ever coming off again after that.

[hiker88]

14 minutes ago, CHA-LEE said:

A better solution is to simply have the "Gas Key" welded to the bolt carrier. When the bolts sheared off on my test AR9 we replaced the bolts, staked AND TIG welded the gas key to the bolt carrier. That thing isn't ever coming off again after that.

Cha-lee,

 

can you you post a pic? I might do that to my “spare” PSA bcg. 

[CHA-LEE]

I don't have access to that bolt carrier anymore so I can't take pictures. Once I proved that the MPX was better for PCC than the AR9 setup I dumped the AR9 like a hot potato. For the welding we simply tack welded the front and back of the key to the bolt carrier then smoothed it out so the weld wouldn't interfere with anything.

[Darqusoull13]

So while I and others appreciate your contributions to the forum, this statement is quite exaggerated.  I'm referencing the part in bold, not necessarily the platform claim that follows. 

6 minutes ago, CHA-LEE said:

I don't have access to that bolt carrier anymore so I can't take pictures. Once I proved that the MPX was better for PCC than the AR9 setup I dumped the AR9 like a hot potato. For the welding we simply tack welded the front and back of the key to the bolt carrier then smoothed it out so the weld wouldn't interfere with anything.

 

[CHA-LEE]

What is exaggerated? I have spent over $5000 on different PCC configs to prove to myself which setup was the best for PCC in competition and the AR9 in both Glock Mag or UZI Mag configuration didn't make the cut. 

 

In the end this is ultimately my opinion and my decision is based on my own research and testing. I doubt that many others are willing to shell out that amount of cash trying every possible PCC config to find the ultimate setup. That is what I did and I stand behind the results and product experiences I paid for.

 

If you feel that an AR9 PCC is the best thing for you in competition, great. Have fun and enjoy your time at the range with it. There is no need to turn this into a Ford vs Chevy argument that does nothing but waste time and make people butt hurt.

[nickbfishn]

Tim, i finally see the light! I’m sure everyone already knows the difference, but I didn’t. The new style bolts have a plateau cut on top where the charge handle grabs them. This way, the heavy key on the first gen bolts can go bye-bye and a trimmed down key can take its place. In the case of your extreme bolt, it is a VERY slimmed down version. 

 

So, with the old version key it is heavy and it gets slammed forwards, hits the charge handle, and cranked backwards when charging. No wonder they fall apart, bad design. 

 

I ordered aomw some new grade 8 screws to repair my old bolt, but It’s going in my Range bag and I’m ordering a new style. 

 

Thanks for your bluntness...the world needs more of you ?

 

 

5 hours ago, TRUBL said:

You did't look at our bolt or our orientation key, do that and answer your own question.......and for the record.....9mm bolts do not have gas keys......get that out of your fricken heads!!! This is why we get the monkey see, monkey do crap. A correctly made bolt engages the charge handle.......not the key........no argument, if you do, you are an idiot