Here are a couple of pics of the “new” profile for Berry’s plated .458 diameter 350 grain bullet.
New profile on the left, old profile on the right:
I would imagine the change in shape came at the request of those shooters who have adopted the 458 SOCOM because (in my mind) the more tapered ogive would feed better in a semi automatic platform.
As I shared earlier, the new profile feeds no problem in my Browning 1886, the old one will not.
With regard's to what charge of Alliant Unique I use for my 45/70 loads using this bullet, I started at 15 grains and worked up to where I got the velocity node I wanted.
15 grains of Unique out of the 30 inch barrel on my Uberti got me about 1250 FPS with very good accuracy but I wanted the speed up around 1450 and was able to do that safely by working up slowly.
If anyone wants the exact load I used, shoot me a PM.
As far as the 15 grain load was concerned, here’s a 10 shot group I fired on Monday whilst conducting load development for the rifle:
10 shots 100 yards off the bench Uberti Hi Wall 15 grains of Alliant Unique and Berrys .458 350 grain tapered profile bullet:
As far as using Unique is concerned, what I like about it it is, it was originally billed as a rifle powder for midrange loads, it isn’t position sensitive (no filler is required) and a little goes a long way.
I know there’s people out there that concern themselves over double charging cases but sound loading practices will preclude that from happening.
Edited to add:
That same load that gives me 1450 FPS out the the 30” barrel on my Hi Wall gives me an average velocity of 1175 FPS out my JM Marlin Guide Gun (although accuracy isn’t as good) I blame that on 60 year old eyes, 18.5” barrel and a stock trigger on the Marlin.