I agree completely. A model 12 in any kind of reasonable condition is among the smoothest cycling pumps ever made. And, even though they are a take-down design, they remain tight and rock-solid for centuries.
On the subject of whether or not to refinish heritage firearms, I confess to being conflicted. The British tradition has been for the master of the house to return his guns to the original maker or a qualified local gun maker to be cleaned, refurbished and refinished as necessary. For this reason, vintage examples of fine English guns can be found in good to excellent condition.
The American experience was a very different one. The average American gun owner was not the lord of any manor. Rather, he was a farmer, a rancher, or subsistence hunter. There were no local makers or even gun smiths, in most cases. The guns themselves, while they could be rugged and serviceable, did not receive a great deal of effort in embellishments and aesthetic finishes. These guns were expected to function for decades with minimal servicing or repairs. They were rarely, if ever, returned to the manufacturer.
These differences resulted in the current state where British guns are refinished routinely and buyers of used pieces expect them to be in excellent condition. Collectors of vintage American guns have been conditioned to look for examples that are in good condition, despite never having been refinished.
Add to this the pressure to honour one's ancestors by preserving their legacy - which translates for some people into "not erasing their mark on life". I don't see any of these traditions as absolute. I have in my collection a Savage model 1904 .22cal rifle that belonged to my Great Grandfather. At one point, I considered refinishing it. But I decided it wouldn't benefit much from such a refinish and that I probably will never fire the gun anyway. I also have a 16 ga 1897 that belonged to my Grandfather. This gun (like your model 12) is in great mechanical condition, but displays the nicks, scrapes, and stains of over 100 years of use. I see this gun as a different scenario. I inherited it when I was still quite young and used it regularly for decades. The 1897 could easily continue to serve in regular use for centuries to come.
So, while I chose to honour Great Granddad by keeping his .22, unmolested, as a memorial, I chose to honour my Granddad by keeping his 16 ga in the field, hopefully for generations to come. This is a shot of the 16 ga. after the refinish:
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I also refinished a friend's 16 ga Model 12 last winter (this gun never belonged to any of his relatives).
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