Someone posted that the lip of the hammer cup on their rifle comes into contact with the tube and prevents the pistol primer from being struck, so it won't fire.
The tube may be too wide for the lip of the hammer cup on some rifles and interfere with the hammer falling all of the way to strike the primer.
I've seen mini-magnets that may be able to be placed inside of the hammer cup that might solve the problem on rifles that have this lip interference.
It would take some experimentation to see if works.
The mini-magnets are sold in bulk in various diameters & thicknesses and are relatively strong.
It would be a small project to fit a mini-magnet inside the hammer cup to see if that would provide enough clearance to eliminate the interference.
Or perhaps the outer diameter of the tube would need to be modified by shaving it down in the right way.
It may not be same on all rifles since their hammer cups may have different sizes, depths and shapes.
The pistol primers may work with some rifles and not others depending on the size of the hammer cup unless an adaptation can be made.
I would like to hear more feedback about whether the pistol primers will work with different rifles or not.
If anyone tries it please let us know how it works out