Added weight helps dampen recoil, so everything you have done sounds right. The monarchs are well suited to heavy recoil rifles. I think you've done all the right things. Think about it this way, a heavier object takes more force to move than a lighter one- if you have 2 forces, recoil, and muzzle brake
deflection, the forces are finite(meaning a set value) Now how in the world can a muzzle brake become more effective with a lighter rifle? Weight of the rifle is one of the main values involved when recoil is calculated. Think of it this way, muzzle brake action acts to cancel recoil by expelling gasses out and back to cause the rifle to accelerate foreward. 25 lbs/sec recoil minus 12 lbs/sec muzzle brake deflection equals 13 lbs/sec total acceleration. 13 lbs/sec acceleration on a 30 lb gun is equal to 13.953 ft/lbs, 13 lbs/sec acceleration in a 6 lb rifle is 69.67 ft/lbs. My gunsmith makes his own muzzle brakes
, and they are very efficient, but not all brakes are created equal. Here's another thing to confuse you, A sound suppressor also dampens felt recoil by containing the escaping gasses and not allowing them to escape forward, causing further rearward acceleration.