On your london, try this:
put 2 grams of lead at 3 o'c, 2 grams at 9 o'c and 1 gram at 12 o'c. Take off replacement grip and add 2 grams around the pallet just above the butt cap about 1.5" from butt end by wrapping two 4" pieces around the pallet. Add 3 grams approximately 7" from the butt end. Replace grips.
Your london should now have the power you want and even more comfort.