I myself would not shoot steel shot through your fine winchester model 12 shotgun.I suppose that there are some out there that will simply say yes to your question,but the fact remains that the steel at the time of your shotguns production was never meant to be shot with steel shot.I would buy a newer shotgun made since 1990 or so and shoot all the steel shot through that shotgun.These can be found for around 200 dollars or less and this will preserve the fine model 12 winchester for upland birds and rabbits.
Not recommended
Not recommended
No.
Not recommended.
Not recommended
Not recommended.
Not recommended.
Needs to be examined by a gunsmith. Answer will depend on what it is choked.
I had the same question so I bought a box of Winchester steel shells [#7 shot target loads 1200 fps] and shot them through my M12 nickel steel barrel with a Briley Mod. Choke tube. The plastic build up was more than I expected but after a good cleaning the barrel still looks good, no damage using target loads and they broke targets. I am going to shoot more through that barrel and keep checking.
I see no reason that you cannot.The steel shot sould work fine in your ranger model 120 shotgun.
You can, but, it will cause some damage.
It can, but, damage will eventually happen. Not recommended.