I recently got a bottomless portafilter that came with a triple shot basket. I have been interchange between the double basket that came with my machine and the triple that I received with the bottomless portafilter. I have started using the triple basket with a double's worth of grind, is this an ok practice? My triple basket has straight walls while my double basket has straight walls at the stop but closer to the button turns into an angled wall.

Thanks guys.

There is on one correct way. However, it you look closely at a single shot, double shot and triple shot basket you should note that each successively larger one has more holes. The manufacturer made them this way for a reason and probably recommends use as designed. That said, experiment away!

I use a trip on my bottomless on the Salvatore pump, I can get 18 grams without hitting he screw on the shower screen. there may be rules but I think of them as guidelines , if it tastes good for you that is all that matters.

Do whatever works. Sometimes under dosing a basket will lead to channeling or sloppy pucks. See how it works for you.

It's wrong if it don't work. Depends a lot on the machine whether it will work or not. If there is too much clearance between the top of the puck and the diffuser, it will tear the top of the puck up and will cause channeling. On my machine, I had to use a triple basket to get an 18 gram shot because the diffuser the was so thick It would jam the puck against the screen with just 16 grams in a double basket.