[mholmes7979]

I bought a AK 74 kit with new US barrel. The barrel pin is .278. The rear sight pin is .160 and the front sight & gas port oins are .12. What # drills or sizes should I use for the above?

 

[MASP7]

http://microadvances.com/guide/DrillChart.gif

 

[74uLLC]

Print this out and stick it on the wall in your shop/garage....

www.ak-builder.com sales the correct drill for the barrel pin. His site is down right now but should be up soon.

 

[MASP7]

Well mine has fractional, number, letter and metric drill sizes... :grin:

 

[74uLLC]

Well mine has fractional, number, letter and metric drill sizes... :grin:

Yup...I like that one too!

 

[MASP7]

AND... standard end mill sizes!

 

[mholmes7979]

Thanks to everyone for the drill chart. It helps a bunch but, what I need now is "how much under the pin size should one drill the barrel". Some web sights say .005 but that seems a whole lot for a pin that is only .12 in diameter.

As you can most likely figure out from my dumb questions this is the first gun I've assembeled. I have a darn good drill press and a Harbor freight 12 ton press but, if I don't get the holes for these pins drilled to the correct size I'll either be unable to press the pins in or the pins may fall out.

Any help on how much under the drill sizes should be for the pin diameters I listed?

Remember I'm a rookie hear and don't know what I don't know!

 

[Storydude1]

Press fit items should have a hole size .001-.0005" smaller than pin size.

 

[mholmes7979]

Press fit items should have a hole size .001-.0005" smaller than pin size.

Thanks

 

[Storydude1]

...

 

[steelcore1964]

If you go a little large on the hole(which is VERY VERY easy to do btw) placing one of the pins on your vise anvil and smacking it 1-2 times with a heavy hammer usually flattens them just enough to be a snug press fit.

+100

 

[mholmes7979]

Being new to all of this I'm going to start out using a drill bit a little too small, then if I can't press the pin in I can always drill the hole a little larger. There is much to learn for the new rookie (me).

If you go a little large on the hole(which is VERY VERY easy to do btw) placing one of the pins on your vise anvil and smacking it 1-2 times with a heavy hammer usually flattens them just enough to be a snug press fit.