Finally got my Arsenal Type 3 Receiver in so I could start my AMD-63 build. I got this receiver because I am not very familiar with the AK family and thought I would use some professional help in a critical area. The Type 3 has the trigger guard, mag release and rails already installed and is heat treated/hardened. The instruction booklet that came with it was very informative and step by step.
Because of the thicker material, Arsenal recommends removing 0.6 mm from both sides of the trunions. Since I had planned on doing the milling/grinding myself, I took several measurements to verify how much material to remove. This is what I found: front trunion measured 31.9 mm thick front to back. The receiver measured 31.01 mm at the front inside at the side bends. The rear trunion was 31.5 mm thick and the rear receiver measured 31.03 mm across the bottom at the bend. Using these measurements, I only took 4.5 mm off each side of the front trunion and 2.5 mm off the rear, then test fit them both. Fit up was perfect. I did not have to take any metal off the top receiver rails as recommended because my trunions fit perfectly with a little rap with plastic hammer. The receiver to trunion front edge was flush and no receiver trimming was required. To remove the metal, I used an angle die grinder with a cut off wheel, grinding slowly and taking measurements at 5-6 locations along the grind area to maintain a true surface. I finished up with a diamond whetstone from Harbor Freight to remove any ridges that might be present.
After verifying that the trunions did not require anymore work, I then marked the holes for mounting the front trunion and drilled them out. I WENT THROUGH 6 DRILL BITS DRILLING THE FRONT TRUNION HOLES. The receiver is harder than the trunions and wore out the bits in a hurry. I have since purchased some Cobalt metal bits to drill out the rear trunion holes.
Because I am still waiting for my rivets and last compliant parts to arrive, my build is on hold until then. I plan on mounting the front trunion then locating proper site for the rear trunion and mounting it. If what I got from Arsenal is representative of their product line, then I would recommend Arsenal to everyone.
PICTURES WILL BE POSTED WHEN BUILD COMPLETE
Because of the thicker material, Arsenal recommends removing 0.6 mm from both sides of the trunions. Since I had planned on doing the milling/grinding myself, I took several measurements to verify how much material to remove. This is what I found: front trunion measured 31.9 mm thick front to back. The receiver measured 31.01 mm at the front inside at the side bends. The rear trunion was 31.5 mm thick and the rear receiver measured 31.03 mm across the bottom at the bend. Using these measurements, I only took 4.5 mm off each side of the front trunion and 2.5 mm off the rear, then test fit them both. Fit up was perfect. I did not have to take any metal off the top receiver rails as recommended because my trunions fit perfectly with a little rap with plastic hammer. The receiver to trunion front edge was flush and no receiver trimming was required. To remove the metal, I used an angle die grinder with a cut off wheel, grinding slowly and taking measurements at 5-6 locations along the grind area to maintain a true surface. I finished up with a diamond whetstone from Harbor Freight to remove any ridges that might be present.
After verifying that the trunions did not require anymore work, I then marked the holes for mounting the front trunion and drilled them out. I WENT THROUGH 6 DRILL BITS DRILLING THE FRONT TRUNION HOLES. The receiver is harder than the trunions and wore out the bits in a hurry. I have since purchased some Cobalt metal bits to drill out the rear trunion holes.
Because I am still waiting for my rivets and last compliant parts to arrive, my build is on hold until then. I plan on mounting the front trunion then locating proper site for the rear trunion and mounting it. If what I got from Arsenal is representative of their product line, then I would recommend Arsenal to everyone.
PICTURES WILL BE POSTED WHEN BUILD COMPLETE