New weatherby Cartridge.

[tj3006]

I think I like this one.
   Of course, I have not seen or shot ones yet, but it seems just right.
   Called the .338 RPM, or rebated precision magnum.  Standard .473 Rim, body like lengthened .284 Win. 
   The Factory ammo puts a 185 grain Bullet out at 3100 FPS and a 225 at 2800. A little less power than a .338 win. I used to shoot the .338 off a bench a lot. 
   But my spine say's no more, and I don't do muzzle breaks.
    I bet this thing kicks less, and with hand loads could be reduced just a little, and still beat the .338/06. 
    I hope they put it in a vanguard soon, cause i am not paying a zillion bux for a MK-5. I guess there is a new 6 lug MK-5 for lighter rounds. 
     But the Howa Built rifles have always been a good buy. 
    I think I would just work up a load for a 210 grain Partition at 2750 , or if my neck can take it 2850, And have a 1 rifle 1 load set up everything from Mule deer to moose. 
             ...tj

[bradshaw]

A .338 Nosler 210 Partition @ 2,700 fps carries a George Foreman punch way out there to make an honest dent on big meat. If your spine ain’t up for the whiplash, why add 100 fps? The Nosler 210 and 225 Partition's are two very fine bullets.
David Bradshaw

[bigbrowndog]

Seems like a Weatherby rendition of the 338-06, my 20” 338-06 gets 2700 with a 210 Nosler and my 26” gets 3000 with 185gmx, and it’s 30-06 brass that I can find most anywhere. Not knocking the new caliber but it seems many manufacturers are simply bringing out new renditions of older rounds or ones that use more powder to slightly beat the older rounds.
This type “breakout” cartridge development seems to have gotten rampant ever since the 6.5cm began accomplishing what the 6.5x55 has been doing in modern guns.
Just my .02 pfennig

Trapr

[tj3006]

Big Brown, Dog you might be very right of course.
But The published data I have seen for the .338 06 does not do as well as your ammo does.
And David , you may well be right to If I 2700 Fps is probably plenty. I would need to start around there and see what it feels like. And where I hunt shots are seldom very long anyway...tj

[bigbrowndog]

TJ, I agree that most published data does not show those numbers, the Hornady 10 data book is where i got my data from and using RL15 and AA2520. Plus I chrono all my loads to verify.

Trapr

[jpw480]

sounds like a 338 RCM.the more cartridges the better.

[bushog]

Dec 16, 2023 15:21:33 GMT -5 bigbrowndog said:

Seems like a Weatherby rendition of the 338-06, my 20” 338-06 gets 2700 with a 210 Nosler and my 26” gets 3000 with 185gmx, and it’s 30-06 brass that I can find most anywhere. Not knocking the new caliber but it seems many manufacturers are simply bringing out new renditions of older rounds or ones that use more powder to slightly beat the older rounds.
This type “breakout” cartridge development seems to have gotten rampant ever since the 6.5cm began accomplishing what the 6.5x55 has been doing in modern guns.
Just my .02 pfennig

Trapr

Weatherby made a pile of 338-06s in their ultra-lightweight model years ago. They're hard to find now...

[Fowler]

I have pondered a 338/06 for years, seems like a dandy elk cartridge to me.

I have a win 70 338 win mag that has been my killing rifle for a long time. It’s an early synthetic stocked rifle and the recoil pad is probably harder than the stock. The load I have run in it for years is a 225gr Partition at 2940fps, so the combo of that stout load and the rifle weighing in right at 8lb with scope and sling makes it a brutal bastard to shoot.

So the practical side of me is drawn to the 338/06 for the reduced recoil. But then the rifle won’t be any lighter than my current rifle, it’s not a tack driver but 1”-1 1/2” groups are typical of the gun. And plenty sufficient for any shot I will take on game. So the overwhelming thought for me is add a great recoil pad (I have a kickeaz slip on on it for bench work) and reduce the loads a bit. I’m sure an elk would never know the difference if I ran that same bullet at 2700fps over the current 2940fps.

It not any fun being practical but the rifle is a winner so keep shooting it.

[bigbrowndog]

Fowler I had Win 70 extreme weather that I had cut the barrel to 21” to make a handy brush gun. The velocity given was what I figured I could get from a 20” 338-06, and use less powder. I was within 50fps and I got to make my new gun into a full stock Mannlicher, something I’d been wanting for awhile.
2940fps from a 225gr. bullet is moving, but it sounds like a do all load. I’d bet an extra thick KickEez pad would make a world of difference, I run one on my 45-90. It helps the pad if you store the rifle muzzle down though because it’s so soft it will spread just from gun weight.

Trapr

[tj3006]

I had 2 model 70 classics.
1 in .338 win mag the other in 7 mm Stw. Leopold VX3s on Both.
My .338 was MOA with RL-19 and a 225 grain Interlock.
My STW was astonishingly accurate.
I was at a range once and a guy saw my group and offered me a price I had to except...tj.

[Thunderjet]

Seems like a neat round. So is the 338 RCM. Add in the 338/06 and you have three to pick from all which will launch the same bullet within 100 fps of the other two.
As great as the 338 RCM is it is dieing a slow death. Try to find ammo or brass for it. Personally I love the RCM’s. Ruger chambered a rifle with a 20 inch barrel, 1/2 inch shorter LOP stock, and factory iron sights. Dang near perfect rifle for hunting in the thick stuff.
The 338 RPM will die the same way.

[tj3006]

You are Right about the Rugers.
Quite possibly the Weatherby too. The .338 06 might be a great alternative...tj

[Lee Martin]

I'll buy one cartridge to add to my collection (which includes every Weatherby released since the .220 Rocket). Aside from that, I'll stick with my all-weather .338 Winchester 70. The .338 RPM isn't filling any void. Though I do like seeing new rounds. Hopefully it'll land them some sales.

-Lee
www.singleactions.com
"Chasing perfection five shots at a time"

[bushog]

All the talk about a .338-06, why not simply shoot a 9.3x62 with a hi BC 250gr accubond at about 2800fps. Easy on the shoulder and hits HARD.

[bigbrowndog]

A 250gr at 2800fps “easy on the shoulder”?? I’d say it’s fairly equal to Fowlers 225 at 2900+. I do like the +30 cal. sub .37’s though, except maybe the 8mm’s never really saw a place for 8mm’s personally

Trapr