Letters to Young Shooters: on the Choice and Use of a GunRalph William Frankland-Payne-Gallwey, Ralph Payne-Gallwey, 1892
http://books.google.com/books?id=Eh9DAAAAIAAJ"The Merits of Chokes and Cylinders, As Applied To Their Effect On Game and Suitability To The Shooter"
http://www.classicshooting.com/shotguns-barrels-chokes.htm The Art of Wing Shooting: A Practical Treatise on the Use of the Shotgun William Bruce Leffingwell 1895
http://books.google.com/books?id=e34EmE3tkfkCThe young sportsman can not be too cautious in handling the gun of some one who hands it to him for inspection. Compliments of the gun are expected and decidedly in order; but the snapping of the hammers and the violent slamming of the gun together, are little things of themselves, but they may bring about a decided coolness on the part of the owner of the gun.
Be careful, therefore, how you handle your friend's gun, and you will be justified if you take the same resolution a sportsman did a century ago when he vowed,
"I will never loan my wife, my dog, or my gun." 
A bunch more
https://docs.google.com/document/d/1x7uk0ii6-lPdWEZj5ctyqr1td19ZcsA5xGGoKBhP9o0/edit
