All Thumbs — The Winchester 99 Thumb ModelProduced in 1904 but patterned after the .22lr 1902

All Thumbs — The Winchester 99 Thumb ModelProduced in 1904 but patterned after the .22lr 1902 single shot, the Thumb Model 99 was different in respect that it lacked a traditional trigger.  Instead the “trigger” was located at the top of the rifle directly behind the firing pin.  It was believed that pushing a button with the thumb would less likely lead to jerking rather than pulling a trigger.  -- source link

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