So I searched for an answer on this. Sorry if it has been asked and answered. I see some variations in the "collars" of bottles, and the differences have caused problems with my capping. The difference can be seen here:
I use a black double lever capper. The bottles like the one on the right seal very nicely. The levers go "over center" towards the end of the travel, and the caps are sealed nicely. The ones like on the left with the smaller collar, not so much. The levers don't go over center and the caps are on very loosely. I lose about one bottle in ten to failure to seal.
So I'm wondering if this is a known issue, and if there is anything that can be done to improve the situation. I have a LOT of these types of bottles, and I've been separating them, but if I can't figure out a way to seal them, I might as well send them to the recycler. I have a buddy who has a bench top capper, and he says he has the exact same problem, so he doesn't use the smaller collar.
Any wisdom would be appreciated.

I use a black double lever capper. The bottles like the one on the right seal very nicely. The levers go "over center" towards the end of the travel, and the caps are sealed nicely. The ones like on the left with the smaller collar, not so much. The levers don't go over center and the caps are on very loosely. I lose about one bottle in ten to failure to seal.
So I'm wondering if this is a known issue, and if there is anything that can be done to improve the situation. I have a LOT of these types of bottles, and I've been separating them, but if I can't figure out a way to seal them, I might as well send them to the recycler. I have a buddy who has a bench top capper, and he says he has the exact same problem, so he doesn't use the smaller collar.
Any wisdom would be appreciated.