Anyone here following the development of this cartridge?

Our 585 caliber is modern bolt action continuance of the 577 Nitro
Express rimmed case, many big game hunters like, usually
set up in double rifles. It has an interesting history, from the old 24ga
size to 577NE, to 585 Nyati with G&A picture of Ross Seyfreid
shooting one in a Ruger #1 under recoil knocking his shooting glasses
off, to the Trex of internet fame knocking guys over with recoil,
to our 585HE the strongest yet.

The 577NE is an offshoot of 24 gauge caliber paper cases, only they went
eventially to brass cases. Back in the 1860-70s, starting first with short 
cases and black powder, cases built like shotgun cases, called the 
577 Snider, then going to coiled brass cases, still with black powder, 
then on to drawn brass cases, called 577 BP Express. then to 3"
and other longer cases with smokeless. The Snider started out with a bullet
of .570" diameter and through the progression to the 577NE bullet
diameter ended up at .585". This general bore diameter of cartridge guns
and muzzle loaders, it is really interesting on how they developed
and were used by military and then hunters over the years. The Snider 
was necked down to make the 577-450 , a military round used all
over the British Empire, by the tens of millions.

Bases of both 24ga and 577NE are about the same. Now we have made a
24ga FH, a slight regression to earlier times, by taking 577NE brass, and
reducing rim diameter to 24ga specs. Two minute job. And
stamp the caseheads 24 ga. 

For shotgun upgrading in power and range, It is all about increasing 
the power in easy to find brass cases, stronger actions, and finding
reasonable price rifled barrels. Same barrels we found for 585, work for 24ga.
The 577NE brass we make 24ga drawn cases from, for example are 
about a third the cost of 600NE brass, or getting turned 24ga cases made.
We could use 24ga thin cases but they are a pain, expand way too much,
with slug loads which makes resizing without crumpling cases a problem.

Very interesting thread here:

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