Re: Winchester Model 12
I don't shoot those, but I do shoot reloads that I worked up for turkey that are 1-1/2oz moving close to that velocity. I've been using them out of my granddad's 30's vintage mod12. I wouldn't want to go through boxes of them, but for the odd ditch chicken or turkey...
I'd say as long as the gun is in good shape and you use the appropriate length you should be fine. Those guns were built like the preverbal brick outhouse. Back when I shot trap I'd run a few hundred rounds a week through mine. And it's still my go to gun for just about everything.
Remember, shoot straight and shoot often.
Good... Bad... I'm the guy with the gun.