Báng súng Picatinny

To build one, you need 

1. Attachment print (either pic center or hole center)
2. Stock (m3, m3 w/ heatset, or 4-40 x 3/8 screws) in either normal or short lengths
3. Matching buttplate to the stock chosen
4. 2x 10-32 nuts (Imperial Mounting) or 2x M5 thin nuts (Metric Mounting)
5. 2x 10-32 x 3/8in screw (slug hardware screws) (Imperial mounting) or 2x M5x10 bolts (Metric Mounting)
6. Depending on the style of stock 
   1. m3 - 2x: m3 x 8mm SHCS
   2. m3 w/ heatsets - 2x: m3 x 8mm SHCS, 2x heatsets
   3. 4-40 x 3/8in countersunk screws (standard slug hardware)
7. Depending on the style of Attachment print
   1. Hole Center: 1x m5 x 30 SHCS, 1x m5 nut
   2. Pic Center: 2x m5 x 30 SHCS 2x m5 nuts

When printing, orient things as seen in the photo below: 

The stock part should be printed fairly robustly (6 walls or so)