Carrier Key hitting Lower.

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[ARCHIVED THREAD] - Carrier Key hitting Lower.

Posted: 2/18/2006 4:49:37 PM EDT

My carrier key is hitting my lower receiver and knocking my carrier key loose. It's a Stag lower with a LMT Bolt group, and a Cav arms colapsable stock. I was wondering if anybody had an idea as to why.

Posted: 2/18/2006 4:54:50 PM EDT

[#1]

Replace your recoil spring and get yourself a heavier buffer, H at least but H2 might be better. That should eliminate the contact.

Posted: 2/18/2006 4:58:20 PM EDT

[#2]

Quoted:
Replace your recoil spring and get yourself a heavier buffer, H at least but H2 might be better. That should eliminate the contact.

That has nothing to do with it. The buffer and receiver extension keep this from occuring. One or the other or both are out of spec.

Posted: 2/18/2006 4:58:28 PM EDT

[#3]

Quoted:

My carrier key is hitting my lower receiver and knocking my carrier key loose. It's a Stag lower with a LMT Bolt group, and a Cav arms colapsable stock. I was wondering if anybody had an idea as to why.

It is impossibe for the carrier key to hit the lower. It is entirely contained within the upper. You might want to look at a schematic to determine what parts you are trying to talk about.

Posted: 2/18/2006 5:04:31 PM EDT

[#4]

Quoted:
It is impossibe for the carrier key to hit the lower. It is entirely contained within the upper. You might want to look at a schematic to determine what parts you are trying to talk about.

It's impossible for you to get your foot any farther in your mouth. Go pull out an upper and see how far out a carrier will come.

rj

Posted: 2/18/2006 5:05:19 PM EDT

[#5]

Quoted:
Quoted:

My carrier key is hitting my lower receiver and knocking my carrier key loose. It's a Stag lower with a LMT Bolt group, and a Cav arms colapsable stock. I was wondering if anybody had an idea as to why.

It is impossibe for the carrier key to hit the lower. It is entirely contained within the upper. You might want to look at a schematic to determine what parts you are trying to talk about.

I believe he is referring to the area of the lower where the buffer tube attaches.

Posted: 2/18/2006 5:08:23 PM EDT

[#6]

Quoted:
Quoted:
Replace your recoil spring and get yourself a heavier buffer, H at least but H2 might be better. That should eliminate the contact.

That has nothing to do with it. The buffer and receiver extension keep this from occuring. One or the other or both are out of spec.

+1. Post this over at the Troubleshooting forum. Either your buffer tube is too long or not screwed in enough, or your buffer is too short or the tip is broken off or the buffer is otherwise damaged and short.

Whenever you have an issue like this you should not fire the weapon again until it is resolved.

rj

Posted: 2/18/2006 8:07:39 PM EDT

[#7]

Two people in this post have proven beyond a shadow a doubt they have no idea how things work, yet give advice anyway.

Typically this happens when someone tries to run a short carbine buffer in a A1 or A2 stock, the buffer will not bottom out in the buttstock extension so the carrier key hitting the lower receiver is what stops bolt/carrier rearward travel.

Like other said, either your buffer assy. is short? Never Seen one, or your buttstock tube is too long? never seen one. You can always drop a spacer into the back of the buttstock to limit it's travel, or I would just reccomend you buy a quality brand name buttstock/buffer over what you have there.

Posted: 2/18/2006 8:15:05 PM EDT

[#8]

Quoted:
Two people in this post have proven beyond a shadow a doubt they have no idea how things work, yet give advice anyway.

Typically this happens when someone tries to run a short carbine buffer in a A1 or A2 stock, the buffer will not bottom out in the buttstock extension so the carrier key hitting the lower receiver is what stops bolt/carrier rearward travel.

Like other said, either your buffer assy. is short? Never Seen one, or your buttstock tube is too long? never seen one. You can always drop a spacer into the back of the buttstock to limit it's travel, or I would just reccomend you buy a quality brand name buttstock/buffer over what you have there.

I noticed that too. It's obvious what is happening, I just wondered why. I got the buttstock, but was having problems with FTF when it got dirty, so I got an H-buffer, and M-16 carrier, and solved the problem, but I just noticed after tightening up my carrier the third time that that was what was hitting the lower. After the first time the carrier key came loose, I retightened, and staked it per Tweaks thread about how to stake them. No help. I think I will get a CMT/Stag Buttstock and see what happens.

Posted: 2/18/2006 8:45:59 PM EDT

[#9]

If your stock is fully closed, your buffer tube looks long.

Posted: 2/18/2006 8:55:34 PM EDT

[#10]

Where'd you get the reciever extension?

Posted: 2/18/2006 9:00:40 PM EDT

[#11]

As others have said, either the buffer is too short or the buffer tube is too long, or something is installed wrong. Perhyaps you could measure the interior length of the buffer tube and the length of the buffer here... others can measure their parts, and it should be easy to see which part, if any, is too short.

Posted: 2/19/2006 3:22:19 AM EDT

[#12]

Be kind of unlikely but the carrier key could be to long at the rear portion.

Posted: 2/19/2006 5:31:24 AM EDT

[#13]

Before you fire this rifle again you should take the buffer spring out, stick the buffer back in the rec extension [ buffer tube ] and then just slide the carrier assy down the tube to make sure it bottoms out with some clearance on the back of the carrier key.

This should be a normal check on any new build along with a check of buffer protusion.

There needs to be some more 'before firing checks' put up on the "Build It Yourself " page. There seems to be a lot more buffer related issues popping up lately.

rj

Posted: 2/19/2006 5:43:26 AM EDT

[#14]

Looks like a Tapco/ Leapers type stock. Flat sling swivel

Posted: 2/19/2006 6:40:45 AM EDT

[#15]

This kind of thing is why I buy factory assembled Colt and keep it all Colt

Bring me some Kool-Aid to put out the flames that will surely ensue!

[ARCHIVED THREAD] - Carrier Key hitting Lower.

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