I am surprised of the results of a test in wet paper with Hornadys 500gr RNSP
The distance to the box with the wet catalogues was 20y. The velocity 5y. in front of the muzzle from the 458win was 2000 ft/s . The bullet did not expand at all. The only different from unfired was the rifling marks and that the lead at the top was harmed. The load is not a max load but I thought I would get a good idea with this load of how the bullet would behave up to 100y
The Bullet on the right side of the two Hornady are a 450gr Lee cast (1200ft/s) shot at the same papers.

Wet paper is not a reliable medium in which to test bullet performance.

Here is a photograph of a Hornady 500 Gr. Soft Nose from a factory round in .458 Lott that I used to kill a cape buffalo last July in the Selous:



Broadside Heart and Lung Shot, 60 yards.

Recovered Weight: 359.8 grs./72%.

Try shooting them into dry magazines, that will destroy most bullets...One medium is as good as another for testing bullets inasmuch as you are testing one bullet against another, not trying to determine what they will do in live flesh,,,,It takes live flesh to do that...even a dead animal is not the same thing as a live animal and the end results are different to one degree or another all things being equal..