I love the Ithaca build! Do you mind sharing where you got the heatshield/bayonet lug? Any mods needed?
The Heat Shield with M1917 Bayonet Mount is available from Numrich Gun Parts out of New York State. They ship to Canada no problem - mine took about a month to arrive.
There are a few mods required to the Shotgun in order to accommodate the Heat Shield/Bayonet Mount. First and foremost is the need to shorten the Barrel to 20" length. The rear edge of the Heat Shield and the rear edge of the Handguard should be aligned with the Bayonet Mount in the proper position on the Barrel. About 1/4" of Barrel should extend beyond the end of the Bayonet Mount when everything is correctly aligned. I use a plumbing Pipe-Cutter for Copper pipe to cut my shotgun Barrels to the correct length. That way you get a perfectly aligned cut at 90-degrees to the line of the Barrel. You will need to run a small grinding wheel around the inside of the Barrel Crown to remove a slight inwards crimp created by the Pipe-Cutter.
Next you will need to grind 3 very short and shallow slots in the underside of the Barrel to fit the 3 Screws which clamp the Bayonet Mount securely to the Barrel. Be very careful when grinding those little slots in the underside of the Barrel to clear the screws - do NOT grind too deeply into the Barrel Wall! Touch up your grinds and the Cut edge of the Barrel with cold Bluing Solution if desired, then mount the Bayonet assembly to the Barrel and tighten down the screws. That's it, that's all there is to creating an Ithaca Trench Gun clone.
Note that all Ithaca "Featherlite" commercial shotguns come with roll-marked bird-hunting scenes pressed into both sides of the Receiver. The genuine Ithaca Trench Guns were based on Model 37 Military and Police Receivers, which were blank. To create a true clone, you would need to sandblast the hunting scenes out of the Receiver sides then parkerize the entire shotgun. The "details" oriented collector could go so far as to recreate the military markings (a "U.S." on the Right Side of the Receiver with "flaming bomb" ordnance mark), all of which is detailed in relevant Youtube videos.
The above is all that there is to creating an Ithaca Trench Gun clone. A used Ithaca Model 37 Featherlite shotgun will set you back approximately $500 CAD on the current used market. The Heat Shield/Bayonet Mount from Numrich Gun Parts will set you back approx $220 CAD landed. Aside from those items, the remaining costs are for consumables - drill bits, abrasives, elbow grease and so forth. And if necessary, the cost of refinishing the converted shotgun with genuine parkerizing, Dura-Park, or CeraKote....
The old Ithaca Model 37 Trench Guns make for a fun and rewarding project - Go for it!
