After a fair bit of testing with the 180gr tsx in my 300 ultramags I have decided to use them for my elk hunting this fall.Group size is around 3/4" for both rifles.This mornings five shot groups were .700" and .730" with the two rifles.However it was quite warm out and I did detect a slight resistance when lifting the bolt on one rifle so I will be reducing the powder charge for that rifle.The other rifle showed no pressure signs and velocity averaged 3400fps.I will chronograph the other rifle when I finalize the load.