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Several years ago a post on riveting the side rails for an AK was live--it is now beyond reply so here are my comments on riveting a side rail.
There are two basic types of side rails.
The Com Bloc rail which uses the front most rivet of the rear trunnion for the side rail rear rivet, and the Chinese type (UTG) that does not use that rivet.
If you already have your receiver riveting done it is easier to use the Chinese type and merely position the rail and drill three new holes.
With the axis pins in place, but the spring retainer or wire removed, position the rail in its correct position.
There is an undercut in the back side of the rail for the center support rivet.
With the rail properly in place clamp it to the receiver leaving room for marking and drilling the rivet holes. Use the depth gauge of your caliper to align the tip of the rail with the top edge of the receiver. This is critical for precision rail alignment. Make certain the your axis pins are clear for inserting and removal.
Carefully place a spring loaded center punch in one of the rail holes and center punch several times to get a good starting hole.
Use a small center drill for the starter hole then drill out with a 5/32" drill--keep in mind that you might also be drilling through the welded bolt carrier rail on the inside.
Check your position of the side rail several times with the calibers and proceed to the next hole with the same procedure as above.
When drilling is completed your rail should be parallel with the top of the receiver.
Make certain that the inside hole is deburred so you flat head rivet will be flat with the receiver.
Use a 5/32" x .500 rivet for good crushing.
Use the AK Builders rivet tool to reach into the receiver for crushing.
I made a backup tool from a bolt for crushing the rivets.
Note: the UTG side rail comes with threaded rivets and nuts but I don't want any loose rivets.
The inside bolt slide rails might need Dremeled for rivet head clearance .
If using the Red Star axis pin retainer it will be necessary to file a half moon groove to clear the rear rivet head.
It is time consuming but you will have a solid scope rail mount.
Comments or procedure improvements welcomed
There are two basic types of side rails.
The Com Bloc rail which uses the front most rivet of the rear trunnion for the side rail rear rivet, and the Chinese type (UTG) that does not use that rivet.
If you already have your receiver riveting done it is easier to use the Chinese type and merely position the rail and drill three new holes.
With the axis pins in place, but the spring retainer or wire removed, position the rail in its correct position.
There is an undercut in the back side of the rail for the center support rivet.
With the rail properly in place clamp it to the receiver leaving room for marking and drilling the rivet holes. Use the depth gauge of your caliper to align the tip of the rail with the top edge of the receiver. This is critical for precision rail alignment. Make certain the your axis pins are clear for inserting and removal.
Carefully place a spring loaded center punch in one of the rail holes and center punch several times to get a good starting hole.
Use a small center drill for the starter hole then drill out with a 5/32" drill--keep in mind that you might also be drilling through the welded bolt carrier rail on the inside.
Check your position of the side rail several times with the calibers and proceed to the next hole with the same procedure as above.
When drilling is completed your rail should be parallel with the top of the receiver.
Make certain that the inside hole is deburred so you flat head rivet will be flat with the receiver.
Use a 5/32" x .500 rivet for good crushing.
Use the AK Builders rivet tool to reach into the receiver for crushing.
I made a backup tool from a bolt for crushing the rivets.
Note: the UTG side rail comes with threaded rivets and nuts but I don't want any loose rivets.
The inside bolt slide rails might need Dremeled for rivet head clearance .
If using the Red Star axis pin retainer it will be necessary to file a half moon groove to clear the rear rivet head.
It is time consuming but you will have a solid scope rail mount.
Comments or procedure improvements welcomed
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