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Kasspur
02-11-2014, 7:19 PM
Anybody know the distance the trigger and hammer pin holes are on a AK? and how far can they be "off". are the tolerances really tight?

ar15barrels
02-11-2014, 7:31 PM
I don't know tolerances, but here is a print:

http://th06.deviantart.net/fs70/PRE/f/2012/286/6/2/ak_74_print_by_gundamgpo3-d5hpg5o.png

Colt562
02-11-2014, 7:39 PM
The tolerances are marked on the bottom under UNLESS OTHERWISED SPECIFIED:

Kasspur
02-11-2014, 7:41 PM
Unfortunately that diagram does not show the distance between the two pins. It only shows the size of the holes. I am trying to get the distance between the two pins to make sure my template is of correct scale. Can someone that has a Ak47 measure the distance between the two pins for me? Center to center.

Colt562
02-11-2014, 7:43 PM
Unfortunately that diagram does not show the distance between the two pins. It only shows the size of the holes. I am trying to get the distance between the two pins to make sure my template is of correct scale. Can someone that has a Ak47 measure the distance between the two pins for me? Center to center.

I would take a second look. If you minus the larger one from the smaller one you get the distance.

Colt562
02-11-2014, 7:44 PM
4.888-3.353= distance between two pins.

ar15barrels
02-11-2014, 7:44 PM
Unfortunately that diagram does not show the distance between the two pins.

The distance between the holes in EACH AXIS can easily be obtained by subtracting the numbers from each other.

Kasspur
02-11-2014, 7:59 PM
4.888-3.353= distance between two pins.

Cool. I'm right between = 1.550

little larger but not by much


Thank you.

SJgunguy24
02-11-2014, 11:45 PM
Cool. I'm right between = 1.550

little larger but not by much


Thank you.

You need to be pretty much dead on or you could end up chasing a nasty hammer follow condition. That means either scrapping the reciever or tuning the FCG, and even that might not fix it.

kcstott
02-12-2014, 5:22 AM
If he can't come up with the numbers reading off a print what makes you think he can take good measurements with harbor freight calipers??

you need to insert oversized pins that fit the holes snug then measure over the pins. you will have to subtract one half of each diameter to come up with your center to center locations.


Cool. I'm right between = 1.550

little larger but not by much


Thank you.


yeah only three times what the tolerance allows, you're off a mile. based on this print you have +/-.005" you are at +.015" not good.

that said these axis locations should be a basic dimension. meaning no tolerance directly applied to them. then need to be on location perfectly and everything else is to reference off the axis pin holes. not the edge of the part and everything stacks as you get to the end.

That said again it's by far the best print i've seen yet.



Now I just though of something too... Are you measuring in reference to the top rails or are you going the shortest distance between the two holes. because that would be measuring the hypotenuse and would not give you the correct dimension


1.5669" center to center across the hyp.

Kasspur
02-12-2014, 4:25 PM
Yes I was thinking the same thing...because I measured from point to point is probably why I have a larger measurement. I will measure horizontally when I get home. That is the reason I thought it would be a little higher because one hole is a little higher than the other this increasing the distance.

Kasspur
02-12-2014, 5:38 PM
Ok, after remeasuring correctly it looks like it's .008 off. Will this make a significant difference?

kcstott
02-12-2014, 7:43 PM
well it ain't good but I doubt it will hurt anything. Just be sure to do a proper function check on the weapon. 1.535 is so nearly close to 39mm I'd call it good you are .19mm large so not great but i'd be willing to bet fine.

Kasspur
02-12-2014, 11:22 PM
Aye, drilled it out and installed trigger group. Function check without problems.