I, together with a few other brewers/beer enthusiasts, had the pleasure of visiting Wildflower Brewing and Blending recently. I really enjoyed the experience because it is so different from almost every other brewery in the world and Topher Boehm was an excellent host.
One of the things that Topher mentioned is that they have a metric buttload of high quality "champagne style" bottles in pristine condition that they are not allowed by law to refill. He is happy to give away these bottles to homebrewers, all you need to do is come and pick them up. I don't have the exact specs on the bottles, but they are very smooth walled, use a slightly larger crown seal than standard long necks/stubbies and I believe they are rated for up to 6 volumes carbonation.
See here for pictures and location: https://wildflowerbeer.com/
Do yourself a favour and plan your trip so you can do the tour and tasting, this is no ordinary craft brewery!
One of the things that Topher mentioned is that they have a metric buttload of high quality "champagne style" bottles in pristine condition that they are not allowed by law to refill. He is happy to give away these bottles to homebrewers, all you need to do is come and pick them up. I don't have the exact specs on the bottles, but they are very smooth walled, use a slightly larger crown seal than standard long necks/stubbies and I believe they are rated for up to 6 volumes carbonation.
See here for pictures and location: https://wildflowerbeer.com/
Do yourself a favour and plan your trip so you can do the tour and tasting, this is no ordinary craft brewery!