Brokennock
Cannon
I agree on the thinner softer leather (but it's what he has for now).@HighUintas, I would suggest a much lighter leather, something that will easily conform to your gun to help seal things up. A possible source for such leather could be places like Good Will or the Salvation Army. Look for old leather coats, jackets and purses. You will be supporting these institutions and finding leather that will work.
This is one of the very few good uses for that Tandy "buckskin" many of us usually like to criticize. The large amount of mink oil and neatsfoot oil worked into the leather takes care of the horrible color