If you want a closer fit of the tank to the APV body use a non-flanged carto. Smokteck makes both: flanged and non flanged. If the O-rings that fit between the carto and and tank are tight enough for your use you may not need a locking or flanged carto. Again, individual use and needs prevail here. Some need locking or flanged cartos and tanks. Some don't. Your use may vary. That's what makes it all good.
Try what works and what doesn't work for you. There is no carto-tank messiah, despite what you may read on these forums.
Try what works and what doesn't work for you. There is no carto-tank messiah, despite what you may read on these forums.