The old Handi Whelen problems are well documented with factory ammo. In some cases, a bad batch of Remington primers were blamed, which makes some sense given that ammo is probably produced rarely, and thus with a certain few lot #'s of components, but these were also the same primers in factory 30-30, 45-70, etc. I get the impression that most guns were sold by the original owners (vs kept and heavily used) or put in the back of the safe. Thought I saw some posts re misfire problems with the new production .35 Whelen Handis too. So I started poking around. CVA and TC also came out with Whelens for the 2009 Primitive season and Hornady came out with more ammo. Lotta life in the round. Lotta problems too.
http://www.mdwfp.com/FORUMS/topic.asp?TOPIC_ID=72234http://www.msgunowners.com/long-guns-f14/encore-35-whelen-update-t3061.htmThis is just way too common across the board with multiple manufacturers of guns and ammo. While I would end up reloading, and probably minimizing the problem. I get the sense that just as a .357 Mag/Max is one of the best calibers for a break open single shot, the .35 Whelen in general, may be one of the worst.
I'll still buy a .35 Whelen Handi gun or barrel when it comes out, just going to lower my expectations. And probably going with a factory fit to have some degree of warranty protectiion. The caliber just seems very sensitive to ammo, primers, headspace, moon phase, hair day, etc.