Dating Iver Johnsons Arms and Cycle works shot gun

Question
I have a single shot Iver Johnson's Arms and Cycle works 12 ga single shot and would like to know the age as for safety in choosing shells. This one has Champion on the left side of the breach and is stamped on the right side as follows..Iver Johnson's Arms and Cycle Works Canada LTD - Montreal and under that has Made in Cobourg. On the top of the barrel  it is stamped..-12 GAUGE-CHOKE BORE- and also   BARREL AND LUG FORGED IN ONE. It has a plastic but plate ( i think ) and it says Iver Johnson in an arch near the top screw and also has an Owl's face almost in the middle of the plate. Any and all info about this gun would be greatly appreciated.
Thanks in advance
Chuck

Answer
Hello Chuck
  Your shotgun is a Champion Model 36, manufactured from 1909-57. I have researched the Canadian address and have only found references to the H.W. Cooey Machine & Arms Company in Cobourg, Ontario, Canada. This company was in business from 1903-61. This does not mean that these shotguns were manufactured there for Iver Johnson. I am doing more research on this. It could, however, mean that the shotguns were manufactured by Iver Johnson Arms & Cycle Works Fitchburg, Mass. USA., and sent to the Cooey Company for assembly. There were several firearms companies that did this during the war years, especially WWII, so they could fill government contracts for military use.
  For ammunition, I would recommend nothing more powerful than a Field (medium) Load, but only after having it thoroughly examined by a competent licensed gunsmith.
  I hope this helps, and thank you for asking for me. Charles Gage