I have calcium build-up in sewer line reducing capacity. Will flooding the line with vinegar work and how long should it take?

CLR or vinegar will dissolve calcium but I seriously doubt this is your issue. What makes you think its calcium and not grease, ahir and body oils?

A Plumber tried to clear line. Could not get 2" cutter down a 4" pipe. Used camera and pipe wall built up with calcium big time. Suggested Jet Blasting but would not guarantee it would work.

You need a different plumber if he says this is calcium.

You need a different plumber if he says this is calcium.

It's extremely rare, but I've seen a few drain lines plugged with uric crystals during bar remodels over the years.

I'm with Widdershins on this one.
I seen uric crystals in some bar rest rooms but never in a sewer line and certainly not calcium.
One last thought. Do you have a water softener installed and if so where does the backwash drain into? Could it be the calcium is really salt? Let me know, Tom

Thanks for all the help everyone. I guess I need to research this one further. Thanks again.

Is there a water softener installed?