Thread: Does reducing the powder charge for a 12 gauge slug safely reduce projectile speed?

Originally Posted by Micky Duck

AP-70N appears in my old paper ADI book 3rd edition november 2000
cowboy shotshell data all loads shown are 1200fps at slowest........thats once n 8th loads.... SEEMS YOUR ap70n is for the heavy end of loads....

As you say, "Cowboy loads," which nowadays seem to favour Trail Boss.

My current task is for 1 oz to 1.2 oz slugs . For your interest, I have a copy of a reply from ADI powders in response to another user's query for subsonic loads and it reads as follows..


"Here are figures supplied to me by the Ballistics Lab at ADI Australia using ADI AS30N


12 Gauge
Case: Winchester AA compression formed (Should be the same in the new Winchester case)
Primer: Win209 or Fiocchi 616
Wad: WAA12 (1-1/8th wad)
Powder: ADI AS30N/Hodgdons Clays
Shot: 1-1/4oz Lead Shot


11 grains = 851 fps @ 5970 psi
12 grains = 910 fps @ 6915 psi
13 grains = 944 fps @ 8610 psi
14 grains = 985 fps @ 9840 psi "

Subsonic loads with similar shot weights however greatly reduced powder charges. It is from these that I create loads for my Spanish Laurona sbs and started with when seeking subsonic loads in the Norwegian silenced Sulun Tac 12 semi .