|17 Winchester Super Magnum|
|Place of origin||United States|
|Parent case||.27 caliber nail gun blank|
|Bullet diameter||.172 in (Script error mm)|
|Case length||1.200 in (Script error mm)|
|20 gr (Script error g)||3,000 ft/s (Script error m/s)||399 ft·lbf (Script error J)|
|25 gr (Script error g)||2,600 ft/s (Script error m/s)||375 ft·lbf (Script error J)|
.17 Winchester Super Magnum, is a rimfire rifle cartridge developed by the ammunition company Winchester in 2012. It descended from the .27 caliber nail gun blank by necking down the blank case to take a .17 caliber (4.5 mm) bullet. Initial loadings will be a 20 grain bullet, delivering muzzle velocities around 3000 ft/s .
The brass case for this round is roughly 50% thicker than the 17 HMR, and the max average internal pressure is 33,000 psi, versus the 17 HMR's 26,000 psi. 
As of January 2013 some retail outlets are listing the ammunition with expected availability of late first quarter or early second quarter 2013.  Hornady will also be delivering a 25 grain V-max loading at 2,600 fps.