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Wyseguy
12-31-2007, 8:09 PM
Ok, just finishing up my first AK build, and I'm having one last problem (at least I hope it's my last) When I installed the bolt carrier and bolt, the bolt goes all the way to the barrell, but the bolt carrier doesn't go all the way to the end. Right now, it looks like the bolt is unable to turn that last little bit that allows the bolt carrier to move all the way forward, but that's just a hunch. This is from an all matching parts kit. If I pressed out the barrell and then checked to see if it was properly in place, do you think that would solve the problem? Do any of you know what the problem could be?
Thanks

BigMac
12-31-2007, 9:41 PM
take the bolt out of the carreir and see if it will lock up fully.


if it will then something is in the way. work it back and forth a couple times looking carefully for whats not fitting and grind it off ;)

Builder
12-31-2007, 10:01 PM
As BigMac writes, make sure the bolt will operate correctly and close all by it self. The bolt should touch the end of the barrel and rotate to lock the lugs. If the barrel was fitted too far aft, it would prevent the bolt lugs from closing.
If the bolt carrier does not move all the way forward with the bolt attached, this could be from the bolt not rotating and holding it from closing or the gas piston is hitting the gas block and preventing the bolt from closing and allowing the bolt to rotate. Remove the gas tube and check to see where the gas piston hits the gas block.
Both of these are related but are from different causes.
Thanks,
Builder

Ford8N
01-01-2008, 5:25 AM
If it is a matching kit, when you put the barrel pin in the trunion, it set the correct headspace. If the barrel was to far forward or backward, that pin would not go in. If the barrel was twisted to much, that pin would either not go in or be a real b***h to go back in. Check the alignment of the gas block. If it is canted to much, it will affect how the BC slides up to the trunion. Also, check to see if the lower rails are meeting up with the corresponding rail/guide on the trunion. It should be perfect. Is this a used matching kit or a brand new matching kit? Used kits tend to work better, bearing surfaces are worn in, ect. Is this a home built receiver or a factory built receiver? If a factory is it an ArmoryUSA, NoDak, Vulcan, Eubank, ITM, Elk River?

This is as much help as I can do with the limited description of the situation.

Wyseguy
01-01-2008, 6:21 PM
To answer a few of your questions:
It is a used matching kit, but doesn't look very used
I was first using a flat that I built, but I also tried it with a NDS-3 receiver I bought from NoDakSpud to use a a reference and have the same result with both recievers
The bolt carrier goes in fine without the bolt.

thedrickel
01-01-2008, 7:56 PM
So it's a screw build?

Try the bolt without the carrier. Basically do what BigMac said - keep working the bolt and carrier with and without each other until you figure out where the bolt is hanging up, and then take corrective action.

FEDUPWBS
01-01-2008, 8:07 PM
So it's a screw build?

Try the bolt without the carrier. Basically do what BigMac said - keep working the bolt and carrier with and without each other until you figure out where the bolt is hanging up, and then take corrective action.



take corrective action= BFH or grinder
Big Mac is a gun pimp listen to him!

Ak47owner
01-04-2008, 5:46 PM
mabe the barrel was installed to far back is the barrel pin in it?

ar15barrels
01-04-2008, 8:16 PM
take corrective action= BFH or grinder


AR builders laugh at these types of threads. ;)

thedrickel
01-05-2008, 5:30 PM
AR builders laugh at these types of threads. ;)

AK builders laugh at people that refer to their "AR builds".

Redchevyman
01-05-2008, 5:38 PM
You may need to push the barrel out a little with the barrel pin in place. The barrel will move a little and your bolt will clear. Do not grind anything until you try this.

tankerman
01-05-2008, 6:38 PM
AK builders laugh at people that refer to their "AR builds".
Are AR's actually builds? I have a couple and when I put them together it reminded me more of playing with a LEGO set than actually building a rifle.

ar15barrels
01-05-2008, 8:46 PM
Are AR's actually builds? I have a couple and when I put them together it reminded me more of playing with a LEGO set than actually building a rifle.

Some would call it assembly, but I do actually BUILD the heart of AR's...the barrel.

www.ar15barrels.com/making.shtml

Ford8N
01-06-2008, 8:09 AM
You may need to push the barrel out a little with the barrel pin in place. The barrel will move a little and your bolt will clear. Do not grind anything until you try this.

Very interesting. I thought it would be pretty solid but the way tolerances are on the AK, it would not surprise me. Have you miked one out to see how much it changes?

Thanks for the tip.

Redchevyman
01-06-2008, 2:25 PM
Very interesting. I thought it would be pretty solid but the way tolerances are on the AK, it would not surprise me. Have you miked one out to see how much it changes?

Thanks for the tip.Never miked one, but I have read that some poeple have had the bolts free up by bumping the barrel forward into the pin.