Well I started fireform today on my 6mm improved in my heavy gun I already have 6mm Bra in my light gun this my improved case to some degree I started by giving a very thorough cleaning I don't believe in one shot an clean this barrel is a button rifle 4 groove barrel with one exception it is a double button barrel I shot 40 fireform rounds at 125 yds an took 5 rounds of once fired an shot a 5 shot group at the velocities on chronograph with 31.1 of H4895 no cleaning after 40 rounds of fireform I think it has potential.