Martini Henry made by George Gibbs

I recently acquired a MH which looks like a military rifle, but has no military markings. It has the following stamped on the barrel :
GEORGE GIBBS.39.CORN STREET BRISTOL

Ther are very little info of George Gibbs on the net.

Can someone please give me what ever info is available?

Will someone guestimate a value?

TX

It's a Commercial or Volunteer Pattern retailed by but not made by Gibb's. My soon has one, It's a good shooter.

Look for Wal Winfers Volume 2 British single shot rifles. It is the Gibbs volume.