I also have a Gibbs A4.
I removed the "original" scope. Bought a Redfield mount (Brownells) and installed a Weaver K2.5 scope (Ebay). What a difference between the scopes! The Weaver is much easier on the eye, the turrets more positive.
I load 155 Sierra MK's, which produce fantastic groups.
One thing to watch for is the front receiver lug. Make sure the relief in the stock is cut deep enough. If it isn't, the receiver and lug sit to high, and the lug will break the stock by not having full vertical contact.
They are a hoot to shoot, enjoy it!
Ed