650 in my personal experience was a pain in the ars. Constantly flipping primers, locking up, and general all around POS. Idea was good when it worked for volume production. Sold it got a 550B and eliminated 99% of problems. Primer seating problems with the 550, yes, but not like the 650. Dillon does not recommend Federal primers in any of their presses, in fact I think says don't use them. Winchester primers definitely little harder, Remington and CCI definitely harder. Using them in a "lightened" action is clickey nightmare. Usually a 1/4-1/2 turn on strain screw from Federal setting will take care of Winchester clicks. If action is smooth wont notice.
As Jim advises, consistent seating pressure and consistent depth setting will cure primer misfire problems. Adjusting the primer seating punch a real plus. Hand seating, highly recommended, is slow, but way to go if you don't mind a slow down. inconsistent primer fire will definitely effect accuracy and inconsistent primer depth will give you this besides misfires.