How do the manufacturers get there reloading data on pressures, group. etc .
Are the loads they shoot crimped or not? Does anyone know??

They have or use expensive Labs with special barrels/actions that record pressure in the chamber. Lately I think there is a hole in the chamber, a pin down the hole, and they measure the pin movement. If that's far from reality . . . well at least you get the idea of it.

Then I guess they shoot some ammo like we do at a target to see how it goes. Probably down a tunnel like the one pictured on the opening page of AR.

Seeing as all factory ammo is probably crimped in some way they probably shoot their stuff that way, but I haven't found any difference to speak of. Especially as their loads are made to shoot in many different rifles/guns.

Apparently the blighters will use any bulk cheap powder that gives them overall consistant results for the shooters that use factory stuff year after year.

I've pulled some factory ammo that went exceedingly well in my rifle and was amazed at the different lengths of cases and different weights of powder, and I doubt they go to the trouble of some fanatical case prep merchants you may read about.