120/10 barrel compatibility

[jkingrph]

I have an old Win. 1200 pump 20 ga and have been wanting a slug barrel. Finally found one on ebay listed as for 1300/1200/120 and it came in today. Stamped 120 20 ga and it fits my 1200. I did notice it has ports as for a semi auto. Why would a barrel for a pump have such ports and is is it safe to use on my 1200 pump gun

Looks like I posted numbers it title header too quick

 

[Alan]

That's a fun find hunting down a slug barrel that actually fits an old 1200. Anything with ported barrels and cross-compatibility between pump and semi-auto guns is really something I'd want a guy who's actually worked on these to weigh in on before you shoot it.

 

[jkingrph]

I sent an email to Winchester customer service. Don't expect a reply until sometime next week, as they were probably closed by the time I sent it.

 

[jkingrph]

Just got a ebay message from the seller,and can return it I will also take to gunsmith and see it he can possibly tap and put some set screws in to seal the holes.

 

[jkingrph]

Winchester replied that they do not recommend it. Local gunsmith who is also a tool/die maker said it would be ok to use as is, not enough gas would escape to hurt. He also said if I wanted to do so, clean and degrease well and fill holes with a dab of JB Weld , which I think I shall try.