From Flayderman's "Guide...". Maker William P. Uhlinger in Philadelphia. Made two styles of 22 cal, and the 32, total quantity 10,000 in all variations, 1860-65. Your six-shot would have a 5,6 or 7 inch barrel. Iron frame standard, brass frame very rare. Walnut or rosewood grips, plated or blued finish. Variations included four different marking (one is J.P.Lower) as well as many made with only the serial number.

Uhlinger bought the tools and stock of William Hankins at the time Hankins went into partnership with Christian Sharps in 1861.

So, if serial numbers were consecutive, your #8xxx would have been made 1864-65.