@ 01:46 pm (GMT)
Nathan FosterThats a shame. When TF started out, there was a major learning curve, much of which you may have read about in my Accurizing book. There were no doubt some barrels in those early days that did not shoot as well as they could and some were truly flat out duds. This was not just about making mistakes, it was a path of discovery, sorting the theory of barrel making from fact. I chose to stick with TF through thick and thin and to help them get to the core of things (again as covered in the book). Others had less patience. In any case, I am glad I stuck it out. In hindsight, it is actually quite naive, arrogant and foolish to expect perfection in year one. Such a thing would be pure chance.
Now regarding your muzzle. An M16 thread is fine. The .750" shoulder is also fine. Remember the rear force is only relative to your hand tightening pressures. Other than this, the brake will be trying to move forwards though in actuality, they tend to freeze due to carbon caking. Enter Neverseize.
You will not be able to take the brake off for a quick shot as the POI will be vastly different, a minimum 6", even with only light porting. You either fit the brake and use it or you don't.
At the barrel length and contour you have chosen, recoil will not be any great deal higher than a Tikka T3 .30-06 or similar. You could start without a brake if you like and see how you get on (you could also for example finish at 30-31" to make up for not having a brake). Otherwise, the brake really only needs to take a small amount of sting out of this, it will not take much to dampen recoil. There is no need to vent to the rear and in turn create a sand blaster that kills your sight picture for several seconds after each shot. The Edge is a slow recoiler. Neither the Lapua or Edge get anywhere near 3000fps with the latest heavy pills and it does not take much to make them comfortable to shoot (subjectively speaking). The stock design you have chosen will be a major factor here, an excellent choice.
Also keep in mind, the longer the barrel, the more strain it will put on your action and the more you need to bed out to around 2.5" or so into the barrel channel. If you relay this to your smith and he doesn't get it, just hang up the phone, done, finished.
Hope that helps. All the best.