Hi Martin

I installed one in my forearm, and one in the butt stock.
They weigh about 11 oz each if I remenber correctly.The one in the forearm is about 5 " long and about a 1/2" in dia. both were bought from Brownells. I also added 3/4 lb of devcon steel in glassbeding of the rifle stock. My goal was to strength up the stock. The additional mass is what matters the most. The finished rifle a Interarms Mark X in 375 and weighs about 12 lbs with a 30mm scope and warne rings and bases. Recoil is not nearly as sharp, the balance of the rifle is great and points real well.
I am back on target much faster. I am hopeing that the additional 2 lbs wont't be to much to carry. If you are in shape to carry a 10 lb rifle is 12lb to much ? I am betting it is not.

JD