Originally Posted by Rustyzipper
...Cash-is-King sold me some 700 plus gr 0.458" LFNs I'm going to load for my 458 American pseudo Scout. After playing with those and healing up I may rechamber to 458 Win mag. Play Well with Others and Be Well, RZ.


Interesting project, a 2-inch-cased .458 American with a "730-gr" WFNGC "Ranger Rick's" from Matt's Bullets ?
Your type of throating will determine how long you can seat it.
You could certainly run a SAAMI .458 WM reamer into it to correct any throating deficiency, but then why not go all the way to .458 WM 2.5" as you say ?

The internet shows some data for similar bullets in the .458 WM+.
Ammoguide.com:

720-grain Ranger Rick WFNGC

[Linked Image]

IMR-4895 50.0 gr
COL 3.592"
24"-barreled Ruger No. 1
MV quoted = 1467 fps


Here is a .45-70 Govt. load in a BFR with 10" barrel:

[Linked Image]

730-gr NEI FNGC (458-645)
H-4198 35.0 gr
COL 3.020"
MV quoted = 1365 fps
Guesstimated pressure of up to 35,000 psi.

If a 730-gr cast lead bullet is 1.737" long,
the 1:14" twist should stabilize at 1080 fps or faster MV,
and a 1:18" twist would require 1800 fps for barely stable.

One good'ol boy on the internet used a 730-gr Ranger Rick in a .458 WM seated to the primary (foremost) crimp groove so COL would be </= 3.340"
in a 1964-vintage pushfeed M70 with 22" barrel:
H4895
52.0 gr >>> 1349 fps
54.0 gr >>> 1618 fps
56.0 gr >>> 1714 fps (case head expansion greater than with factory loads)
58.0 gr >>> Brass extrusion marks on case head, even greater case head expansion, and scary chrono data: 2064 fps, ERROR, and 1680 fps (for the three readings)
60.0 gr >>> BLOWN PRIMER and one reading of 1717 fps

Bubba concluded that he might be OK with 52.0 to 55.0 grains of H4895, but your mileage may vary.

Ron aka "Rip" for Riflecrank Internationale Permanente
NRA Life Benefactor and Beneficiary
.458 Winchester Magnum, Magnanimous in Victory
THE WALKING DEAD does so remind me of Democrap voters. Donkeypox.