Any of the 5/8x24 threaded JP Enterprises Recoil Eliminator Brakes will be compatible with your Ruger American. However, model MPN:JPRE-424B is designed for a bull barrel. So if you do not have a bull barrel equipped you can use either MPN:JPRE-324 (Black) or MPN:JPRE-324S (Silver).
The JP Enterprises Dual Chamber Recoil Eliminator will not work for 9mm. These JP Enterprises Dual Chamber Recoil Eliminators are for .223/5.56 and .308 calibers.
You can use any JP Enterprises Dual Chamber Recoil Eliminator with an internal diameter of 0.308" bigger. MPN:JPRE-424S.
This specific recoil eliminator can be used with bullet diameters of 0.35"-0.4" or anything smaller.
The correct JP Enterprises Dual Chamber Recoil Eliminator for an AR10 platform rifle would be MPN:JPRE-424S. Essentially you can use any muzzle brake with an internal diameter that is 0.308" or bigger.
For the AR-15's you would want: J5-BMB-JPBMBRE-JPRE-2
For the Ak you would need a thread adapter as AK's have a left-hand thread. Something like this: 3GL-MZD-THAK-AK47-TA
And then you would need this brake for the AK: J5-BMB-JPBMBRE-JPRE-324
It does not come from the factory able to accommodate 9mm. However, according to JP, the .281 models can be modified in the following manner: This model's final exit hole of .281 will accommodate bores up to .243/6mm. This exit hole can be enlarged to accommodate bores up to .358.
I cannot see the model you are referencing, but if you choose the 5/8x24 model, yes it would work.
You need the models with the 5/8x24 thread pitch.
Yes, these brakes would be effective. Just get one of the models with the .281 exit diameter.
These are not compatible with the .454