Ron Smith gain twist barrels

[buckbrushoutdoors]

I'm having him put together my first semi custom build and would like some feed back on his barrels. I've heard there is pretty good possibilitie that the gain twist can increase velocity?
He's building me a 35 whelen barrel. My hope is that I can get over 3000fps with a 180 gr bullets.
My old rifle would spit 200 gr superformace at 2920fps hoping I can achieve more.