ORIGINAL: txhunter58
80 grains of 777 and 460 grain no excuses gives me 8 inch groups at 25 yards! Tried 80,85,90,95, 100, 105,110 grains 777 with no excuses. Have not tried pyrodex though. And I am going to try the new platinum 338 powerbelts with 80-100 grains of 777. Those are my next totry along with themaxiballs.
I use only 75 gr. Shuetzen with the 460s NE's today & it was great out to 100 yards.
Why did you start with 80 gr? The "rough" 777 equivalent to my 75 grain Schuetzen FFFblackpowder load is 65 gr. 777.... enough powder/downrange thumpto take an elk at 100+ yards. Another load to try is roughly 70 gr. of powderwith Buffalo Ballet 270 HP. The only Maxi I would recommend for that 1-28" would be the MaxiHunter 270s. Lastly, you can also custom-order some monster conicals around 460 gr.from the BullShop Company. For your T/C, I would not exceed .5035 in diameter & I would suggest all lead, #2 lube and gas check-bottoms for your options.
So many Colorado folk buy sabot guns to shoot conicals. Amazing!