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Posted: 5/28/2011 11:29:18 AM EDT
| I have an AK74 parts kit with new U.S. made barrel. But the barrel does not the the barrel pin slot cut out. What is the depth of the slot? And where does the slot need to be on the barrel? |
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You have to have the headspace set first. Then drill for an over sized pin if it does not line up (should do it anyway if its a non matching kit, and even then you should check the headspace). To gauge that you have to measure it in a couple places in that hole to get the offset, to determine what over sized pin you need.
Head over to AKfiles and start doing some reading, about a weeks worth before you press a pin in there. Lots of things can go wrong if you rush this portion of your build. Not trying to discourage you, a build can be done with simple tools, but you need to do certain things, and have certain tools to build an AK properly. |
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on a virgin barrel, after setting the headspace, I use an end mill to start the hole. This gives me a flat surface on the barrel shank, so when I follow up with a drill bit, it is less likely to want to walk. Drill half-way on both sides, with an undersize bit, to further reduce the chances of the bit wandering and creating an oval hole on the exit side. Then take a bit .001-.002" smaller than your pin diameter and spin it at high rpm and plunge it in and out. This reduces the propensity of any spiral cutter to make an oval hole.
Ideal would be a reamer 0.01mm smaller than the pin. I've found pins 0.01 larger than the hole, but hot the other way around. |
| I agree I like the reamers from Curits he sells them in sets for the right application and also the pins....If you have a virgin build I would get the smallest that will fit tru the hole already in your trunnion incase it has to be head spaced in the future you have the chance to use the oversized pins.. Dont take it from me but the standard is like .290 to .300 I know the oversize pins are like 302 to 312...... Just look in Curtis,s site to find out..... |
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