Home Forums Hunting & Shooting Express Rifles and Big Bores Only The great 458 Winchester. Everyone should own one at least once

Sir Larry,
A parallel-sided throat of about caliber length
and only 0.0006" to one thou bigger in diameter than bullet caliber
would be about like the .375 Wby Magnum and 6.5 Creedmoor.
No flies on that !
That is way more generous throat than you find on a SAAMI .458 Lott.

Back to the Gary Sitton article, found it in my three-ring binder of .458 articles.
In 1990 to 1991 when the article was written (published for the May-June 1991 issue, RIFLE 135)
the .458 Lott was a wildcat still, with Art Alphin lobbying SAAMI to homologate it.

Sitton developed his own load data in a Ruger No. 1, factory .458 Winchester Magnum, re-chambered
by David Miller who "simply pulled the barrel, ran the Lott reamers into the .458 Winchester chamber, replaced the barrel, and I went shooting."

Note that he said "reamers" plural.
A rougher and a finisher ?
A case body reamer and a separate throating reamer, or what ?
A non-belt-cutting, throat-merging, single reamer is what Jack Lott used to do the same conversion.
Very imprecise of Gary to not define his rifle's throating more specifically,
or maybe even realize that he might have a residual .458 WinMag throat in his rifle,
like the original Jack Lott wildcat ?
Lott of kissing up to good buddy Jack Lott was done nevertheless.

Note also that Sitton said his chamber allowed brass to stretch to 2.820",
not like the SAAMI .458 Lott chamber that has 2.810" respective measure.
More like the SAAMI .458 WinMag that allows 2.520" stretch-to of the 2.500" brass.

Looking at the original drawing Jack did for his wildcat reamer,
it allowed 2.650" ahead of the non-cutting belt stop.
Add 0.220" for the height/length from breech face to top of belt
and total chamber length would be 2.650" + 0.220" = 2.870"
HOLY COW !
That is what the .450 Watts Magnum requires, if allowing 2.850" max brass to stretch to 2.870".
So Jack used a .450 Watts chamber and changed brass length to 2.800" maximum,
because that was easiest for fire-forming .375 H&H brass which shortened on fire-forming.
Trimmed up nicely to 2.790" trim-to and 2.800" maximum being a nice round number for squaring up the case mouths.

At the time the article was written, IMR-4320 had already been discontinued,
the only powder Sitton could find to get his 500-grainer over 2300 fps.

Now we have so many better options and no need to re-chamber to .458 Lott.
The .458 WM+ loads in a factory Ruger No.1 SAAMI .458 WinMag will beat a SAAMI .458 Lott
like a kid with a wooden spoon and pots and pans on New Year's Eve.