Currently I've made cannabutter twice. I had no issues with the process, except the yield. I used 1 cup of butter to infuse my flower with and only got 1/2 cup in return. Do you lose that much butter during infusion? Did I not squeeze my cheesecloth enough? SOMEBODY PLEASE HELP!!!
I don't use cheesecloth.
Certainly a harder squeeze will get more butter but temperature of what's being squeezed is important. I usually wash my big hairy hands well and brave the highest temps I can stand, then I exert maximum pressure with my bare handed super simian grip on the infused weed.
The butter is in a more liquid and flowing state at the higher temps as opposed to collecting and stubbornly adhering to the wet weed at the lower temps. Remember butter acts like an oil and likes to stick to stuff when it's in a liquid state.
In the event choking the hot wet weed spinach isn't your thing, consider using a decent potato masher and a good sturdy metal colander placed over / supported by the container / pot you'll use for the liquid to solidify and stratify in. Then, mash away!
When doing it that way, I maneuver the weed in the colander to get maximum drippage and only do a workable size piece at a time. If I think there's still more butter to be had and the weed has cooled a bit, it's not a bad thing to reheat all the pre squozen weed grenades (is "squozen" even a word" ?) and do a round two. Add a bit of water if needed for the reheat. Also it's not necessary to reheat for long the trichomes have probably already been infused in the butter, you're trying to release the butter from the weed at this stage rather than release the trichomes into the butter.
Good luck.