SO sorry you have such a powerful axe to grind. Maybe you can post a picture of one of Kirby's brakes so we can all see the similarities.
Now this brake idea came about in 91 or 92 by a machinst friend of mine who made one and only one for a 50BMG. In 1998 I had all the brakes in my hand. They made and installed a brake. SHot the gun in which the concussion cleared everything from the table including hats and hearing protection. Ears rang for several days! SO back to the drawing board. The next brake was designed with the first port closest to the shooter set at a 90 degree to the bore to shear off the back blast from the four other ports which were set at 35 degrees to the rear.
1. I have never made a brake one, like pictured in any of these photo's.
2. I have a friend that has a program in which I asked him to scale down a Barrett 50BMG brake to fit my handcannon application. Requirements were representative of the brakes sitting on the shelf in my friends shop.
3. I sent the original and other cad drawings to Jim See who has had and installed Kirby's brakes. He tells me that there is no comparison!
4. I purchased a couple of Kirby's brakes,Hollands brakes and a number of other manufacturers brakes along with a $225. Barrett brake and had all sent to the shop (Different friend)in Idaho where they were all tested on my 338 X378 handgun. The report was- Very Severe backblast on short barrels. He did like the Holland brake. It is currently being used as is Kirby's big pain killer brake on 338 X 378 Improved rifles.
5. SInce I have never had one of Kirby's brakes in my hand it would be really hard for me to duplicate it. I can very easily prove what I have said to be true.
I am told that the inside of the muscle brake is where the major difference is from other brakes. I would not know as besides my own made brakes, Vias and Scott Nulls brakes and one Holland quick discharge I have never seen or used another brake. SO if you are crying foul? If I have never made one. If I have never had one in my hand? How is it you are calling me a copycat?? OH, forgot something, I pay for the brakes and their installation just like everyone else.
Hope this helps Pit.