Anyone making 1:4 twist barrels?

Saw a lot of info about it being intended for 1:3 or 1:4 and since I didn't want to SBR or run a brace on my AR-10 I was wanting to seek out doing a 14.5 p&w or a 16"

I would be shooting suppressed and worry about the projectile being spun too fast on a longer barrel and starting g to expand when exiting the barrel and dink my can.

Not sure if that's a valid concern or not.