Thread size for suppressor help

Hi. I'm a newbie to the forums (and hunting) and been reading and learning a lot. These forums are great!

I'm hoping someone can give me some advice on suppressors.
I've picked up a second hard Vanguard Weatherby 7mm08 as my first gun, and it was already threaded, but I don't know the thread size.
I'm wanting to keep an eye out for a second hand one (I've got a very tight budget to get into hunting otherwise wife will introduce the couch to me :) ).
I took it into Hunting and Fishing and they said they will just send the gun away to get a brand new suppressor fitted.

Does anyone have any ideas how I can find out the size? A friend had a Ruger 10/22" that was factory threaded, and his factory thread protector fitted my Weatherby. Is that a good indication that it's the same thread size, or are protectors a bit generous on size?

Any advice appreciated :)

Without seeing it I'd guess 1/2x20 seems to be the common one take it to an engineering shop and get them to try a die on it that will tell you just be carefull where you point it and take the bolt out

Agree, if it fit the factory thread on a 10/22 it was likely a 12"x20tpi aka 1/2UNF

Popped into Fortress Fasteners this afternoon and thought I'd try them before an engineering place. The guys there were really helpful. Turns out it's a 1/2-20.
Now time to watch the forums for a suppressor to get me started. :)
Thanks everyone for the advice on possible sizes and to try an engineering place.

get a half decent one not one of those crappy springs and washers ones