AK74 Receiver Rails Measurement

[TheWabbit]

I'm still having some trouble with my two AK74s that are using a 100% receiver from IO (yeah yeah, I know). I got them cheap but I'm regretting it now. I'm having extraction issues and trying to figure out why. When someone has their AK74 open, can you take a measurement of the distance between the bottom of the bent receiver lip (that the bolt carrier rides) and the top of the receiver rails. I don't have any other 74s so I don't know what the correct measurement should be. I'm wondering if the extractor is too low.

Thanks.

 

[ottoclicker]

The rail height specs are the same for the AKM and AK-74.
In a proper receiver with stepped top rails, the lower bolt rails should be 6.0 mm to 6.3 mm below the step of the top rails.

 

[TheWabbit]

Thanks. I figured that was the answer but wanted to confirm before I move to other possible causes for FTE. I used a 1/4" drill bit (how I weld rails) to confirm the rails are straight and the correct depth.