True but the pressure levels for saboted ammo is different, I've heard of people loading their own .50 sabots up to 260+ grains of powder. They said even with this high of a loading there was very minimal felt recoil.
There is also the chance of the sabot opening up and contacting the brake, this would not be a good thing. Having your brake explode or pieces of the sabot coming back at you could ruin your day.