7 stw barrel length

[Rydinef]

So I’ve wanted a 7mm stw for many years now. I got a smoking deal on a Remington 700 7 mag that’s currently at the smith getting rechambered for stw. My question is about barrel length. It’s currently 24” but I’d like to run it suppressed and am thinking about having him cut it down and thread it. In all my research I’m only seeing 26-28” recommended. Would going 18-20” be to detrimental for the round? Hoping to get 7 mag performance from a short barreled 7 stw.