If theres no letters yours is from the same time period as mine. I think that's the only pic I've got of mine, it's really not that good looking, the blueing is all gone, it's just brown, theres a few ugly spots on the barrel where it rusted at some point, theres a chunk missing from the forestock, some idiot decided it need swivel studs as put them in all crooked.
But it sure point nice, and the trigger feels great.
You're gun is probably worth somewhere from $50-$150 depending on condition, but seeing as it was you're grandfathers, just hang on to it and go shoot some grouse.