It's not in my strongest wheelhouse, but I believe it's Constantius Gallus (or possibly Constantius II). The lower portion (exergue area) of the reverse is too blurry for me to read. It may help if a more clear image were available. This great webpage may be a help for you to enjoy the path of I.D.'ing it: http://augustuscoins.com/ed/Gallus/ (Scroll down the page a little to the "FEL TEMP REPARATIO" section.) Also, this is the reverse's correct positioning orientation:
the reverse is tough to make out; but I think that this is it-- Constantius II A.D. 351- 355 D N CONSTANTIVS P F AVG, pearl diademed, draped & cuirassed bust right; Δ behind bust. FEL TEMP RE-PARATIO Soldier spearing fallen horseman; A beneath horse. In ex. [A]SIRM RIC VIII Sirmium 40
