I'm considering thinking that these brake tests that "free float" the rifle are a bit bogus when comparing different brake designs.
What would each "feel" like to a person?
What if a strain gage were placed between shoulder and recoil pad? What would that tell ya.
I did the "free float" thing with my 375 Allen Magnum with a large PainKiller brake and a 350 SMK launched at a bit over 3300 FPS.
The rig slid back 14.5 inches.
However when I'm prone behind it movement is maybe an inch and I can spot my shots.
I't kind of satisfying when the big girl speakes with such authority and shoots well at long distances..
Just say'n....
You make some good points Roy, and hear is my take on different types of test to measure recoil.
While trying to duplicate real world test and recoil numbers this is what we found.
First was to rule out perception. (If you ask 10 people to guess how much recoil a rifle produced there were 10 different numbers).
We also looked at strain gauges and found that they did not respond fast enough to get reliable results and we did not like to restrain the rifles in fear of damaging them to get good results.
Next was the free floating type of test. It would not repeat because of many different elements and also could not be measured. It did however have one good attribute, the rifle was free to move instantly, but with no damping inertia rendered it useless and inconsistent.
We also looked at a weight system but it was not real world because the rifle had to overcome the weight of the rifle and the weights that it had to lift before it could move at all skewing the recoil values.
When a rifle is fired buy a person, it will move instantly and as the rifle recoils more, more body weight is added as compression of the shooters body is increased. So we decided to try and duplicate these parameters and start with as little preload as possible (Just enough to move the rifle back in battery and stay at or below 1 pound at rest) and increase the load on the rifle as it moved further back.
With these things in mind, we looked at real world movement of different shooters and found that measurements were very consistent with the same shooter. But When we changed shooters, this distance (Measured by computer) changed, but was very consistent.
We realize that the design we came up with is not perfect, but it did duplicate conditions and is very repeatable And without exception less that 1 ft/lb off from computer models/calculations no mater what the rifle weight and cartridge power is.
It is however something mechanical and things can go wrong so each time we start testing we use the same rifle and load every time as a bench mark to assure everything is in proper working order.
The machine we test on has no agenda or knowledge of the brand of brake we are testing so the results are real and not perceived. And as a results of impartial testing, many of MY perceptions and
beliefs were drastically changed.
I don't consider my self an expert, But do consider myself qualified to talk Intelligently about muzzle brakes due to the amount of impartial testing we have performed.
J E CUSTOM