The 'New Era Nitro Hammerless Sidelock' was a Batavia Leader with twist barrels sold by Shapleigh Hardware.

The 'New Era Gun Works New York Nitro Hammerless Boxlock'



was a tradename gun for a store named 'The Fair', that also offered Syracuse Arms Co. boxlocks with the same name.
Ad from "American Field" April 20, 1901 (I think courtesy of Researcher).



More tradename Bakers are here
http://www.picturetrail.com/sfx/album/view/17434920

ANY vintage gun must be assessed on its own merits, starting with the barrels. I am of the opinion that if the barrels are deemed 'safe' for black powder, they are safe for low pressure smokeless loads. You will note the ad states "fully guaranteed for nitro or black powders"

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