That's corect Bonde.
Here's a copy and paste from one of Tony's posts here explaining it better that I did. I've used it in several rifles and it works very well.

"I am the one that rediscovered the 75% rule.

You use a bullet that is as close as you can get to 75% the weight of the full power bullet and use the SAME powder charge."

I like the sculptured breech of those barrels! Nicely done!
And the $12,676.86 isn't bad either