I've come across a number of problems relating to Tolerances and Material hardness.
First example, The M76 receivers are all over the place when it comes to tolerances. I and three other people had issue in the placement of the magazine cuts. For example, all of those receivers were machine so the magazine sat to far down in the from end. How much? Over 2.5MM! This problem made the ammo feed under the bullet guide, jamming the weapon.
Another problem, The rear of the receiver was mis-angled by 5 degree, which would force the stock to aim upward at the buttpad end. Also, there were areas that they machined away too much material and not enough material in other areas.
There most recent batch of receivers have one Major problem, the center position of the Bolt is not centered (concentric) to the center line of the barrels. Most were off upwards to 1mm! This will cause the cartridge to jam/wedge into the chamber, not allowing the action to fully lock into battery.
I know what most people are saying when reading this, that i shouldn't complain because they are the only company making the M76 or Galil receivers, but I was fustrated to know that I had to pay more in repairs and re-heattreat then what the receiver originally cost me. Also, If ORF didn't make receivers, someone else would have.
BTW, don't ask about the Galil receivers, there's not enough space in the thread to list the problems.
Hopefully, ORF will invest into a quality control program, then I will happily purchase their receivers once again.
sleestak