I couldn't contain myself anymore with Memorial Day leftover deals & Father's day sales
I picked up a Ruger American 308 22" barrel w\ Nikon
Was thinking of getting barrel threaded for possible suppressor
I'm sure others have done so...
Any recommendations?

Adco is popular.  Why not buy the Predator to begin with, it's threaded already.  Not available as part of the sale?

Predator didn't come with scope & shorter barrel

My 308 Predator has an 18" barrel and is threaded 5/8X24 (model 6974). I would have preferred the barrel to be 16" like the ranch models to keep it as compact as possible with the suppressor installed. My shooting needs don't require the extra velocity gained with the longer barrel. If you hunt or move around with a full length suppressed rifle for very long you will understand that longer isn't always better :)  To have a proper 0.72" diameter shoulder for 5/8" threads you may have to have the barrel cut back some anyway depending on it's profile. Don't worry though, you may lose a little velocity but you'll gain rigidity!

Side Note:  Ruger model 6959 is a 22" barreled Predator in 308 Win. I think it was a distributor exclusive so it may not be easy to find.

I ordered a Predator .308 from my LGS.  It came in.  I took it shooting.  It was very accurate, but then I noticed the 18" bbl seemed rather long, and the velocities were higher than I expected.  It was the Lipsey's model with 22" bbl.  A local gunsmith cut the bbl to 16.5" and threaded it 5/6x24 for me.  Still shoots great and lost 300fps with the 125gr handloads I was using.  Makes it MUCH more handy for the suppressed shooting I do with it.  No regrets over getting it shortened and threaded.  

I used this guy, and a bunch of other folks as well, Ad on EE

$50 Barrel Threading

Same here. Morgan has threaded many guns for me including my Browning BAR ShortTrac which all of the other shops (large and small) told me couldn't be done. He also fixed my factory threaded Mini 30 Tactical thread shoulder as Ruger doesn't seem to think a square shoulder is necessary and left it with a taper to the threads. All work has been great and he's my go-to for anything that will host a suppressor.

Well I'm going to have another opportunity to get what I want
The deadbeat on-line retailer sent the wrong version of this rifle to my FFL
and I rejected. We called them & they don't have the version they sold me available.
They apologized & don't know how they could have made the mistake & started to question my order, but they finally took responsibility
Refunded my purchase price & are paying for return shipping.
I am now shopping again for entry level bolt 308
Lot's of good contact & advice guys...Thanks

Don't shy away from the American! Now you can give a serious look at a factory threaded model which will remove the hassle and cost of shipping a new rifle to get threaded. I can't recommend the two Predator model .308s enough, but I recommend suppressed bolt action shooting more!