chetmarks

I shoot a .503/460 grain Bull Shop from mine very well. I use a .125x510 wad card under the bullet and 90 grains of T7-3f. The wad insulates the bottom of the bullet from the heat of T7 and keeps the bullet lube from contaminating the upper part of the powder load if the bullet is left in for a length of time, especially in warmer weather.

Also mine is a M97 Ultra-Mag and has the longer barrel so I burn the 90 grains no problem... the shorter Whites I think a majority of the DWB shooters are using 70 grains of real BP.