Walt wrote:
That is a nasty one. Do you have a decent wood clamp? If so, I would use some wood glue from the inside and clamp it for a couple days to give it a chance to set. Once the glue has set, then give it a good coat of linseed oil on both sides.
PLUS:
Add a couple of "pins" that go directly through the crack at right angles. I've fixed cracks like this by drilling a hole the same size as a piece of brass brazing rod (no flux on it). Cut off a piece of the rod that's slightly longer than the total length of the hole. Rough up the surface of the rod by rolling it on a wood surface with a flat wood rasp on top of it. The rasp will create all kinds of dents and burrs after a few strokes. Mix up some epoxy adhesive. fill the hole and wipe some on the rod. Pound the rod int the hole and then clamp as above. When the epoxy's cured, along with whatever you used to glue the wood. then flush trim and sand off the ends of the pins.
Shotguns are relatively "Low Pressure" rounds. The forend that shows the crack doesn't add to the strength of the gun, it's just a means to hold it. Make sure the buttstock is intact and if you find any cracks repair using epoxy and pins.
As for loads, stick with the lowest "Dram Equivalent" loads with lightest shot total weight. That will reduce the recoil. This shotgun reminds me of the old Browning "humpback" and they kicked like mules.