Updated Factory Short Magnums/Ultramags

[Batsin]

But if you stuff a 215 Hyb into a 300WSM case to fit in a standard SA length mag, the ogive/bearing surface junction is literally down inside the neck. You have a gap around the case mouth and bullet jacket. Plus, there is so much bullet stuffed into the case, you get compressed loads before you ever hit pressure, so velocities are really hobbled.

That's true, but the OP wanted to buy off the shelf ammo for his 20" short-action magnum. A heavy 300 WSM is pretty much the best readily available option these days.
All of the older short magnums benefit greatly when put in a longer action and loaded to longer COALS. That means hand loading and a longer action, things the OP didn't want.
If you can find bullets with longer ogives, you can get away with the factory chamber, although I don't particularly like the WSMs' SAAMI chambers (no freebore, just a simple taper).

 

[Batsin]

I built an AR 15 with a custom 22" 30-25 WSSM barrel, before the 300 OSSM came out.

I wasn't very clear in an earlier post, but I was thinking about a 30-25 WSSM or 300 OSSM in a 308-length or AR10 action. That would allow a long-ogive bullet and still keep most of the shank out of the powder column. The barrel could have a fast twist and a long, tight freebore for good accuracy.
Velocity would probably still be in 30-06 territory but the sleek bullets would increase effective range a bit.

I haven't run any length calculations, so the WSSM case may be somewhat shorter than needed, but it is the only production case that I can think of that comes close to what was requested.

 

[DDB TX]

I wasn't very clear in an earlier post, but I was thinking about a 30-25 WSSM or 300 OSSM in a 308-length or AR10 action. That would allow a long-ogive bullet and still keep most of the shank out of the powder column. The barrel could have a fast twist and a long, tight freebore for good accuracy.
Velocity would probably still be in 30-06 territory but the sleek bullets would increase effective range a bit.

I haven't run any length calculations, so the WSSM case may be somewhat shorter than needed, but it is the only production case that I can think of that comes close to what was requested.

Ah OK. 25 WSSM case is 1.67 inches long; AR 10 magazine will take cartridges 2.825 inches or even a bit longer; giving you 1.155 inches of space for the bullet to poke out.
If you are going to go AR 10 or short bolt action, though, might as well go with the 300 SAUMs (case length 2.015 inches, 2.825 overall length, 0.815 inches of bullet hanging out) or 300 WSMs (case length 2.1 inches, 2.86 inches overall, .76 inches of bullet hanging out). Or the RCM. Or PRC.

 

[Batsin]

Ah OK. 25 WSSM case is 1.67 inches long; AR 10 magazine will take cartridges 2.825 inches or even a bit longer; giving you 1.155 inches of space for the bullet to poke out.

Going back to the first couple of posts, the OP wanted: a) a short action magnum, and
b) "to be able to just go buy hornady precision hunter 212s off the shelf for a short action short barrel 30 cal short PRC"

The head height (amount of bullet hanging out) of the 300 PRC is 1.12" and the 212 Precision Hunter is designed specifically for that cartridge. Lancetkenyon was complaining that bullets like the Berger Hybrid 215 (1.598" oal, .799"ogive length) would not work well in a 300 WSM because part of the ogive was in the neck and so much of the shank was in the powder compartment.
If you don't mind a lot of the bullet inside the case and a long jump to the lands, the 300 RSAUM with a fast-twist barrel could do it. A 30-6.5PRC or 30-338RCM could do it as well, but we are back to 30-06 velocities. That goes against modern cartridge design, though. Even the 6.5 PRC has a .925" head height and it won't fit into a 308-length (2.81") or even a WSM-length (2.86") short action. The 6.8 Western has a .935" head height.

 

[pecker_wood]

What is Sherman doing that Hornady or Winchester can't do? Is it a licensing thing?

 

[Phil Rizzo]

Using a 40* shoulder, less case body taper and designing reamers that allow for seating depth that maximizes powder capacity, by putting the bullet where it belongs.
He doesn't have to deal with factory gun SAAMI standards.

And they fit better in medium length actions, for mag length reasons in general.

 

[JAYgs8163]

Using a 40* shoulder, less case body taper and designing reamers that allow for seating depth that maximizes powder capacity, by putting the bullet where it belongs.
He doesn't have to deal with factory gun SAAMI standards.

And they fit better in medium length actions, for mag length reasons in general.

And they work just fine in Short Actions. On another note….

I've been contemplating build a 270WSM as I load for a friend with the 150 Berger VLD Hunter going 3200 FPS. Thing is super accurate and is a basic factory Weatherby 25" 10 twist Vanguard. It's just hard to find brass for them which is quite puzzling as a number of Factory Rifles are still chambered in the 270WSM.

 

[lancetkenyon]

What is Sherman doing that Hornady or Winchester can't do? Is it a licensing thing?

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View attachment 519463

Can't? Nothing.
Won't? Retooling, R&D, $$$, etc.

Besides, then Hornady will be making their crappy brass for these cartridges. No thanks.

 

[pecker_wood]

30 cal, 210 to 220 grain, short action, 20 inch barrel, 3000fps. I don't understand why it's so difficult. Hornadys bound to have some of that superduperformance powder back there somewhere that'll get it done

 

[MagnumManiac]

300RCM dead. 300WSM almost dead. Wats next?

What's next for the dead list is this; all PRC's, Western, SAUM and any other short Precision BS cartridge that are hyped to HELLO and just don't cut the mustard…
If a 24" barreled rifle feels unwieldy, try hunting with a 30-34" barreled rifle and then you'll think the others are pee shooters.
BTW, this is a Long Range hunting forum, how many of us do you think are hunting with a rifle running an 18" barrel??
As to factory short action, short barrel rifles, THEY see the trends, but realise they won't last, just like electric vehicles, the fad will end.

Cheers.

 

[pecker_wood]

What's next for the dead list is this; all PRC's, Western, SAUM and any other short Precision BS cartridge that are hyped to HELLO and just don't cut the mustard…
If a 24" barreled rifle feels unwieldy, try hunting with a 30-34" barreled rifle and then you'll think the others are pee shooters.
BTW, this is a Long Range hunting forum, how many of us do you think are hunting with a rifle running an 18" barrel??
As to factory short action, short barrel rifles, THEY see the trends, but realise they won't last, just like electric vehicles, the fad will end.

Cheers.

34 inches??

 

[pecker_wood]

Can you send me a picture of your 34 inch hunting rifle all done up?

 

[JP_Gunner]

Making me consider posting up my 700p it's a 20" 300 saum

 

[Mike D Texas]

I dont know man, ole gold trigger built my 6.8W stalker 20 inch for $512 then they mailed me a black friday check for $100 lol

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I dont know man, ole gold trigger built my 6.8W stalker 20 inch for $512 then they mailed me a black friday check for $100 lol

View attachment 518685

That's because the 6.8W is destined to die. Nobody wants a .277 caliber "new" cartridge.