Mudcat,
Why a brake on a .223? Your set up has to be heavier than my 12 VLP and I hardly feel any recoil. If you have a 1 in 9 twist first try some Black Hills from Fulton Armory. The 52 gr. match is the least expensive and 50 per box. My 1 in 9 twist loves this stuff followed by the 69 gr. SMKs. Off a heavy front rest with rear bag and a decent scope your rifle should show at least 1/2 moa if your using consistant cheek weld, trigger squeeze, breath control etc. Take your time between rounds so as not to rush or push shots or run out of breath and tire.
At 100 yards I can sight on golf balls on the berm in 3 to 5 seconds and turn them into dust with the 52 grain match hp running 3400 fps. Is your parrelex dialed out? Just wondering...

Pete K.