Allient publish 2 loads for the 470 NE.

One RL19 one RL22

Both achieve the standard regulation velocity.

Why would one wish to use a powder that they do not recommend, that also requires a filler medium and add more variables to the equation.

I can see nothing to be gained, except a very small change in recoil due to the lesser mass of ejxector and slightly lower (pennies cost) and potentially everything to be lost.

I am sure that if they thought RL15 and half a pillow stuffed on top was a good idea they would have said so.

Regards