Looking at pics in other thread and as Jim says, it is bent just below the muzzle ring, Its possible to straighten it without heat and make up a simple jig and press it straight, once straight then you may need to work on the inner dimensinons of the muzzle ring but start with getting it straight first.

The muzzle ring itself could be a little oval due to the bend so would make up a dolly or two and use these to re-form the muzzle ring, at the last stage there may be the need for a slight file but dont go near it with a file untill the above is complete and your cofident with a file.

If it does need a file then this area will need to be blued or browned depending on the colour (I cant tell by the pics).

Obvious you need to take the grips off before any work, don't want to teach how to suck eggs but I,ve seen some strange working practices in the past......

If your a bit unsure then I would leave it as is, maybe trade it at a later date, or sell it to me.