DRM - Bill Ruger demanded that the GL handle like a Dixon Round Action. That model gave the Ruger engineers a weight/balance/moment of inertia spec. This spec is very different from the RL. The barrels of the GL must be relatively thiner than the RL or the spec can't be met.
Two GL's with 28" bbls and 14 1/4" LOP weighed in at 6# 10 oz, balanced 5 1/4" ahead of the trigger, had a unmounted swing effort (MOI at balance) of 1.41, and a mounted swing effort (MOI at butt)of 6.84. A Dixon RA of 28" bbls - 14 1/8" LOP had 6# 4 1/2 oz - 4 3/4" - 1.17 - 5.98. The average of many Brit game pattern guns is 6# 8 oz - 4 1/2" - 1.45 - 6.4. A W-W 101 is 7# 12 1/2 oz - 4 3/4" - 1.75 - 7.73. As you can see, the GL is very much like a Brit game patern gun. I seem to lack a RL 12 gauge - I'll fix that shortly.