This is my caliber, 416. wild cat, chamber is for 416. brass, and bullet is 10.3 (.413), home made bullet is 16.2 g (grain???) and the muzzle velocity is 950/955 m/s
The rifle is one Ruger n.1

Look my bullet:

Nice looking bullet.

A 16.2 gram bullet is around 249.5 grains. Be a real little rocket from a 416 Weatherby.

What cartridge case is the wildcat based on?

Is a simply wild cat brass 416 mag. and bullet .413, normal bullet for 416 is 300 gr.

My chamber is in 416. and barrel 10.3 mm (.413) one very rocket!!

Tell us more about the bullets.

Soft points? solids? who makes them? etc etc....

Is a hollow point in copper (it is a bullet solid with the hole in top, with point in polymer) the first prototype was in bronze league but results too much hard.
Besides I have had to widen the gangs of taking in how much the first ones were too much ends. I have also added a light boat tail, has been done with a CNC.

This is my frist prototype:


This was the ballistic result of the first prototype but I have realized that he didn't deform, shooting in the sand for so much or changed with the softest copper:

Very interesting cartridge, it would be amazing to try some of those light bullets like that in a similar caliber. .413 would also work in a .405 Winchester rifle. Especially in a Ruger #1 like yours.

I think maybe you should make drive band bullets in .416 and sell them.