Confused in California
Yup the new jars will still let you know if they are not sealed. As I sit here 5 of 12 pickle jars have sealed in the kitchen judging by the sound. Not a processed pickle but the boiling brine is hot enough to pull a seal as the jars cool. These are going in the fridge to cure where they last a year. I just push them to the back.
The rubbery/orangy seal on inside of 2-piece canning lid set ups is meant to be heated up a bit before canning to soften it a bit. Beside boiling/sterilizing jars and rings, "they" tell you to give lids a certain amount of time (check directions for specifics) so seal gets pliable.
I'm a yard sale & thrift store fan, and ALWAYS interested in canning jars... especially WIDE-mouth quart ones... obviously with NO chipped edges or even smallest cracks. If you have a Food Saver vac system, they make an attachment that allows you to seal just the lid (no ring required) onto wide-mouth jars. This gizmo if NOT for sealing perishable stuff that would ordinarily go into a hot water bath, but I LOVE it for small pastas, rice, beans, etc... dry stuff. Lid comes off with very little coaxing from a can opener and can be re-used MANY times, as long as ya don't dent/bend. It keeps stuff that technically doesn't go "bad" but could go stale/rancid.
I have a few of those zinc lids... from collecting "old" blue jars. Thinking, in their day, there was some kinda ring or gasket that went inside to make a seal?? Bought a dozen "old" jars at a yard sale with unusual lids/rings. They're gold/brass color with an hour-glass cut out in center. Each has a clear glass disk that sets inside the ring... again there must be something soft/moldable to create a seal??
Have tried hand at pickles several times. Successful but whatever pickled seems to get a bit soft after a while stored on a shelf? I prefer making a brine (sorta sweet & sour, usually a bit salty, sometimes spicy), boiled to make sure sugar/salt is dissolved and to let pickling spices to... do their thing!?! I pour over and stash jar in fridge.
Now "they" say you'll DIE if ya do anything short of pressure canning... well, maybe that's an exaggeration. I DO know that pressure canning is REQUIRED for stuff containing meat! In dead of winter, when I'm looking for ANYTHING to do around the house BESIDES CLEAN, I'll start 2 big VATS of stock... chicken & beef. I use a basic pressure cooker/canner (that's what it said on the BOX) to process those jars. It takes a little longer, really isn't much different from regular water bath method, doesn't need to be WATCHED (except for timer) and DOES NOT EXPLODE! Does anybody have FIRST HAND experience of an eruption... not "my grandmother had a neighbor... pea soup all over the kitchen... 2nd degree burns" experience??