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Posted: 10/3/2005 6:35:50 AM EDT
[Last Edit: 10/3/2005 6:40:16 AM EDT by aceface]
Headspace – everyone seems to says check it – but not what to do about it  – well ok.

Check done – head space too much (about .010 too much).

Now what?  Try different bolt? -  barrel trunion? -  take to the gun  doctor? - – Hmmmm this could get expensive – might be cheaper to just buy another kit and  start over.  I guess it would help to have a pile of parts laying around.  Any suggestions?

Lesson learned – never buy a kit unless you KNOW it has matching numbers.
Link Posted: 10/3/2005 6:40:30 AM EDT
i have a simlar problem with a MAK-90, so it isn't just kits.  What i was told was that i would need to punch out the barrel pin,  get the barrel to where it needs to be to properly HS, drill an oversized hole for an oversized barrel pin.

Makes sense to me, that's why that MAK is sitting waaay in the back of my safe.
Link Posted: 10/3/2005 7:59:19 AM EDT
Sounds logical – but ez?  Has anyone here done this?  Wonder where one would get this oversized pin – it probably would have to “homebrew”.  
Link Posted: 10/3/2005 8:43:09 AM EDT
no there is or was a place to get them, i'll see if i can drag up a link.
Link Posted: 10/3/2005 8:47:57 AM EDT
Remove barrel pin..Adjust  barrel for proper distance.. redrill for larger barrel pin..install larger barrel pin..done
Link Posted: 10/3/2005 8:59:07 AM EDT
The standard barrel pin is 7mm (0.276) so if you can find anything a little bigger you would be fine.  There are places that sell 7.5mm barrel pins but I will have to search as well...  

Just get the pin out and measure to confirm the size you have.  I have read that some of the Rommy kits may have 7.5mm pins already...

I have not had to do this yet myself...
Link Posted: 10/3/2005 9:10:11 AM EDT
[Last Edit: 10/3/2005 9:12:02 AM EDT by Hammer in PA]

Originally Posted By aceface:
Headspace – everyone seems to says check it – but not what to do about it  – well ok.

Check done – head space too much (about .010 too much).

Now what?  Try different bolt? -  barrel trunion? -  take to the gun  doctor? - – Hmmmm this could get expensive – might be cheaper to just buy another kit and  start over.  I guess it would help to have a pile of parts laying around.  Any suggestions?

Lesson learned – never buy a kit unless you KNOW it has matching numbers.



I take it your saying it failed the "No-Go" gauge.  Meaning that your bolt closed with that gauge.  Have you tried the "Field" gauge?  Just because a kit has matching numbers doesn't mean it will headspace correctly.  Can you send the kit back?
Link Posted: 10/3/2005 9:58:56 AM EDT
Yo - Hammer in PA

>>Have you tried the "Field" gauge? <<
Not having a field gauge I put a .008 shim under a no go and it still goes.
I put a .010 shim under the no-go ganges and it won't

>>Just because a kit has matching numbers doesn't mean it will headspace correctly<<
I'm sure that is true but I would say the odds are MUCH greater on a kit that has matching numbers of being OK.  This is my first kit out of 5 that doesn't have matching numbers and It's the one with headspace issues.

>>Can you send the kit back<<
Well I'm sure I could try - but the kit only cost me $80.00 and looks super (like new),  other than this - and I'd like to try and fix it -  But If I can't I'll have my first pile of parts.


Link Posted: 10/3/2005 10:11:24 AM EDT
Wouldnt it be easier to buy a Good drill bit a bit bigger and use the shank end instead of ordering some pin, Im sure Lowes sells something that would work, even some bar stock out of steel would do it
Link Posted: 10/3/2005 2:38:21 PM EDT
I've used the shanks on the dril;l bits before.  Actually, I wouldn't be concerned over only 10 thou.
Years ago I had one worse than that and I put several thousand rounds through it.  Disclaimer on and off.....
Link Posted: 10/3/2005 7:08:24 PM EDT
bottom of the page....http://globaltrades.com/ak_receivers.html


"Assembly Pins & Oversize Pins You only need the standard pins for normal assembly of AKs, but if you run into problems, the oversize pins can save you a lot of grief. They are about .001" bigger than the standard pins. We bought these to solve problems in our rifle assembly business, but we decided that we should make them available to our customers."
Link Posted: 10/4/2005 6:26:23 AM EDT
MSC Direct<--- you can order pins here, just cut to length.

7mm drill rod<--- For those needing to replace those pesky barrel pins

... and HERE is the stuff that GT sells (I think)..  It is sized at 0.0014 over the 7mm barrel pin.  It is the same as a "J" sized drill bit.

Keep in mind that these are a couple of bucks for 36" of pin.  Just cut to fit.
Link Posted: 10/4/2005 9:03:39 AM EDT
[Last Edit: 10/4/2005 9:18:54 AM EDT by aceface]
Yo aztroop and Mack_Bolan

If the barrel is moved toward the receiver .010 to clean up a headspace issue  -- if my caluclations are correct - to keep everything "round"  the minimum oversized pin should be .020 over stock size.

MSC Direct looks like a cool site!!

Yo TerryG3
>>Actually, I wouldn't be concerned over only 10 thou.<<

I have shot the gun and spent cases show no signs of a headspace issue (flattened primers - cracked/split cases - streached cases).   .010 might be able to be considered a borderline problem.
Link Posted: 10/4/2005 6:38:24 PM EDT
I had a case where both gauges fit in a matching numbers AMD-65 after assembly.  I pressed the barrel pin back out, and pressed the barrel in a little farther until the no go gauge didn't go and pressed the barrel pin back in. There is a range, despite what logic would tell you, where the headspace is adjustable by barrel depth in the trunnion without redrilling the pin for an oversized one. That is what I would try first.
Link Posted: 10/4/2005 7:35:06 PM EDT
You can also try pressing the barrel in more with the pin in, or using a large brass punch and hammer to push it out some with the pin in there, depending on which direction it needs to go.  Although you aren't off by much anyway.
Link Posted: 10/4/2005 8:47:35 PM EDT
Yo old_school_1960 and 2FALable

>>There is a range, despite what logic would tell you, where the headspace is adjustable by barrel depth in the trunnion without redrilling the pin for an oversized one.<<

Interesting - might be worth a try.

ALSO I wonder which way the barrel  tends to drift - In (toward receiver) form recoil or out from breach pressure???? I assume the pin keeps it from going one way or the other.   If  "in" maybe one could just relieve that side of the cut in barrel slightly if after doing what you suggest and the pin pushes the barrel back out.  This might be worth a try for SMALL adjustments.





Link Posted: 10/5/2005 3:23:30 AM EDT
Well because I'm a dangerous freak I know what I would do.. but it's just me.  Being off the amount you are, I'd go fire the beast and few times and then recheck the headspace.  It's either going to get worse or get better...

But I certainly wouldn't advocate anyone else do something just because I would.
Link Posted: 10/5/2005 4:37:04 AM EDT
Barrel defintely moves outward during firing.  Lets just say that someone I know found a different method for barrel removal when they forgot to put the barrel pin in before test firing.  
Link Posted: 10/5/2005 10:46:56 AM EDT

Originally Posted By BillSXT2002:
Barrel defintely moves outward during firing.  Lets just say that someone I know found a different method for barrel removal when they forgot to put the barrel pin in before test firing.  




I have done lots of stupid things, but That takes the cake!...


Thanks!...I feel much better about myself now!..
Link Posted: 10/5/2005 5:29:30 PM EDT
i dont think it really maters much if your part numbers all match if and only if there all new,..try smaking the barrel in or out then re-install the pin,  and check headspace
Link Posted: 10/7/2005 7:23:39 PM EDT
Is it necessary to HS an AK kit with matching numbers?  There seem to be a lot of Ak being build, but I have a hard time believing everyone owns GO / NO GO gauges.  Thanks
Link Posted: 10/7/2005 8:32:11 PM EDT
it's like putting on a condom, before "making love" the the bar fly you just met.

Sure, you might come out "ok" but is it worth the risk?



well, a lot of people do it and it's all good, however, a few people do it, and die.



Link Posted: 10/8/2005 3:54:22 AM EDT

Originally Posted By millsusaf:
Is it necessary to HS an AK kit with matching numbers?  There seem to be a lot of Ak being build, but I have a hard time believing everyone owns GO / NO GO gauges.  Thanks



all i can say was my factory built MAK90  has excessive HS and routinely tears the ass end off of the fired case leaving the rest in the chamber.. I won't shoot that gun anymore until i have corrected the problem.
Link Posted: 10/8/2005 10:10:16 AM EDT
anybody ever wonder why those broken shell removers are sold for AKs?
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