I don't have any experience with the 20VT but it looks like a cool round. Is this a target round or a hunting round? I could look it up but I'd rather hear about it first hand by someone that has one.I'm looking at muzzle brakes right now for a 20 Vartarg I'm gathering parts for. There is minimum recoil on the 20VT, however I've read where so shooters were having a little problem seeing their hits/missing at closer ranges until they put a muzzle brake on.
I like the Holland radial brakes, but they are a little $$ and then you have to have a smith install it to time it to the barrel.
I also like the Quick Fire Muzzle Brake from Mac's Gunworks. The draw back I see on the Quick Fire is it has a timing nut that is exposed. You set the brake where you need it and then run the nut up to it to lock it in place. I think this would work great, I just don't care for the look of the nut.
I don't have a mill to shave a little off at a time for the Holland brake to get it timed right, so is there another way to set up a brake that has to be timed to the barrel?
The reason I like these two brakes is you don't have the blast going downward that will blow up debris.
I don't know if this will help unless you have a lathe but I built my own brake for a Marlin 45-70. I had to have the barrel threaded because I didn't have the tools to remove the barrel. Anyway, I'll post a pic of the brake I made on my lathe & borrowed mill to drill the holes that I later hardened and blued myself.