I built that pistol in Photo Shop it is a program for editing photos so that pistol is just a dream gun right now but I am into long range pistols and may have to build it this year just to see how it will work. What kind of FPS are you getting from the 6.5-284 with 140g bullets and what powder are you using in your pistol with the 129g bullets. I am shooting a rifle in 6.5-284 and like the 140g Amax bullets it has a 1 in 8.5 twist I think I would go with a 8 twist for the pistol. Do you have a pic of you pistol you could share with us.
Crow Mag
Crow Mag