BSA Mercury

[dashsix]

If the pivot pin holes are egg shaped ish then there not much you can do.If not excessive open sights will keep on target a scope wouldn't.But i'm sure you knew that already

Had this problem with my Supersport, pivot hole in breech block was oversize, I made and press fitted some phosphor bronze bushes, and bored back to standard size.

[jackal1]

The more i look at this gun the more i think it isn't worth the the money and effort to make it right again. It has a hairline crack across the pistol grip, a bent barrel, worn pivot pin holes and would want ceracoting to make it look tidy. That's before we get to the tuning bit.

[pajj]

Can't see it being financially justifiable on any terms. Even if you get it performing perfectly it will still be a non original repaired Mercury. You have to decide is it worth the expense in terms of an hobby/interest project. If not give it to someone who enjoys tinkering. IMHO tuning kits on old BSA's isn't the best return on investment any way.

[evert]

These kinds of projects are best if you can do the work yourself, AND enjoy it.
I find great pleasure in getting old guns working well, but I usually dont refinish them.
Theres no financial gain in working on old guns like this.