I was using 5/16 c360 brass rod ... I have made screws out of steel bolts ... I look on Ebay under "vintage tap die" you can get these really nice tap and die sets that are 100 years old for cheep ... I look for any thing that has 26 TPI and 30 TPI ... all the other krag screws are 26 TPI English bicycle thread ... im still looking for a 8-30 die the must have them somewhere .. 

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