Guys
It's been a long time since I conducted all that research and I'm too lazy to pull out my files; but I honestly don't recall a lot of "hyperbole about self regulation". I'm not a gifted gun mechanic like you guys; but to my knowledge the only self-adjusting wear mechanism in the entire gun design is the single bit top bolt incorporated into the opening lever that intersects a slot in the rib extension and designed to wear right to left as the gun is used. This device, and rib extension, was modified in 1902 to increase bearing surfaces at the point of bolting and create a stronger bolt; but that's it, and the cocking rods do nothing other than cock the hammers when barrels are lowered. SAC claimed that the wider barrel lug allowed for less wear on the hinge pin; and I'm sure that is true, but I've also seen SAC guns that required hinge pin work to put the barrels back on face. Occasionally one will find an example with the bolt broken off the top lever; but I've seen more examples with broken rib extensions (all were second and third models). How that might happen, I have no idea; but it has happened to me personally. I was bunny hunting one afternoon when the dogs pushed pushed a cottontail my way; I rolled the bunny with a 1901 AE model SAC, and when I opened the gun to reload, something hit my boot. I didn't think anything of it until I closed the gun and it flopped open again. At that point I noticed the bottom portion of the rib extension was missing. I scrambled around amongst the weeds and found the missing piece; then noted it was broken in such a fashion whereby it could be put back and remain in place. I then carefully closed the gun and noticed it remained tightly locked; so I then plugged both tubes with #6's and hunted the balance of the day with no problems, being very careful not to lose the broken piece whenever I opened the gun.
Good luck on finding that 20-bore; the "hunt" for that elusive model is actually the most enjoyable portion of the entire process.
