Looking at the 416 Rem Mag brass.

Just buy the Hornady basic belted magnum brass and run it through your 416 rem full length sizer with a decent amount of imperial sizing wax on the case.. Cost $30 for 50. I use this brass to form 375 Weatherby. I run it through the 416 die first then the 375 die bingo 375 Weatherby brass!!!

i use Jamison in my 505 Gibbs and 470 NE. Good Brass

I use Jamison in my 450/400 and 450NE-like it better than Hornady

Jamison is my favorite 470 Nitro brass. The only problem I have seen is a large variation in weights between two lots.

Norma is very good but expensive.

There have been several Hornady brass that would not chamber due to rim thickness out of tolerence.

I bought some Rigby brass. It was by far the worst. Very rough finish around the rim. It is for emergengy plinking only.

I have used Jamison in 470NE and 500NE and have had no problems with it.

Thanks for all the input AR!! Wealth of info this AR thing .

Jamison has been great for me so far.