What do you mean..."function as intended" ?
Yes, you can trim the barrel as short as you like, provided that you leave room to reinstall the suppressor. It may be VARY close to the air cylinder and ot the stock.
A clean end cut, with a nice clean crown in the bore. The crown doesn't have t be large or exotically polished, or a huge radius, or anything fancy. Just a clean, burr-free chamfer.
Then either a new thread of your choice, normally 1/2-20 . Or an adapter to attach to the end of the barrel to be able to attach the suppressor.
All pretty straight forward. What..."was at the end of the barrel", needs to be "redone" at the end of the barrel...where-ever the new end is !
The barrel below is almost 3.0" shorter than when I removed it from its box. Still shoots fine, as accurate as it was with its full length barrel. Maybe a few feet per second slower, but that of no matter to me.
View attachment 328552 Mike