Tejano,
One thing seldom said, is that the .240 Weatherby case is more narrow than the standard '06 case. While the cartridges tend to get lumped together, they have a different volume, shoulder design and neck length.

I did have the opportunity to chronograph a 6mm/06 rifle that frequented the range about the same time as my .240 and it did have a genuine 100+fps advantage over my .240 Wby at that time with the available powders we had back in the 80's.

Because I had exposure to a lot of cartridges, when the gun laws tightened to the point of gun registration in the mid 90's that also included adding serial numbers to barrels and also registering them, I chose the .25/06 because it suited so many Aussie target animals and would cover decent range shooting across the many flat country areas as well as ridge to ridge shooting I did.

So would the .240 Wby, but as stated previously, there were no bullets over 100 grains available to us in 6mm so the '06 did offer an extra 20 grains for larger animals like red stags, large billies and the pigs we commonly hunted. Another point was that Barnes was relatively new when this decision was made and after hunting a couple of states here in the US by that time, I realized the value of the .25/06 for pronghorn and mule deer which I by then a;so had experience with.

Almost 25 years later, the only thing I have changed is to move the 6.5-20 Leupold off the .25/06 and onto a 7mm Remington and fit a standard 3-9 Leupold so the rifle is more suited for whitetail hunting. The 6 power bottom end didn't work for me in the woods.

When truth is ignored, it does not change an untruth from remaining a lie.