Period-50 glider gun is an extensible true period-50 glider gun discovered by Dean Hickerson on October 13, 1996. It is based on a period-44 gun by David Buckingham and the p50 traffic jam oscillator to restore the blinker, as well as 2 copies of this mechanism to restore the blinker in the middle. It can be made to have more than 1 barrel. 
In 2004, David Bell, produced a variant using only a single oscillator with a glider loop. It is possible to restore the blinker by using queen bee shuttles but that makes this gun pseudo. The true period would then be p150. With the discovery of 55P10 in 2018, the true period-50 gun was vastly reduced.