I suppose this thread can also be informative as well. In the future😉
My first barrel was Tippmann https://www.ansgear.com/Tippmann_16_Sniper_Barrel_Black_98_Custom_p/tippmannsniperbarrel9816.htm. I can't say I was unhappy using it, but after switching to Madbull V2 6.03 I felt a huge difference. Analogue - Prometheus (aka Prommy), 6.03 (+/- 0.01mm). I haven't tried this brand yet, but it also has a lot of good reviews. But all these options for the upgrade, of course. Here are simpler models.
In my opinion, 6.03 is the best option. If your barrel is too tight, it will break your ammo. Too wide = low accuracy (you bought a sniper rifle for more precise shots, right?).
The best way to find your right barrel is to try different models. It will be cool if you will have this opportunity.
John-