Help me find a 338 Cartridge

[MSU Marksman]

I'm looking for the most efficient cartridge that could get a 250 gr 338 bullet to 2800 fps, or a 300 gr 338 bullet to 2550 fps. Yes I know there are rounds that will push these weights much faster, but that's not what I'm trying to do. And yes I know I could "load down" some of those rounds, but again, that wouldn't make it too efficient.

 

[Long Time Long Ranger]

The 338 win mag is going to be your closest bet. Your parameters are just above the 338 win mag unless you had a very fast or a long barrel. The 340 wby is the next step up but it is closer to the ultramags and you would be loading it down to reach those velocities. You said most efficient so you wouldn't want to load the 340 wby down a couple hundred fps. A hot 338 win mag is the closest to what you want to do. The necked up short mags can't get there. The 338 win mag is an excellent cartridge that is easily capable to near a half mile and a great choice for an all around rifle.

 

[RockZ]

The 338 win will work out great.
But if you want to have a little fun you can always make a 338WSM

 

[jcvibby]

338 Win mag will work for those requirements. I would go with the 338 rum though. Not really one of the big magnums like snipetac, lapua, big bear or edge but will get some good FPS for sure. That might be your best comprimise.

 

[LouBoyd]

What's your definition of "efficiency". Muzzle energy/propellant energy or terminal energy/propellant energy? If the latter then heavy slow low drag bullets are the most "efficient" since they give up a smaller percent of their energy pushing air out of their way. Your stated velocity requirement makes the 338 Win Mag the choice for efficiency. I doubt a 338-06 can make it. Without the velocity requirement a 338 Whisper (338 BR) is a lethal subsonic which is a far more efficient (in terminal energy/propellant energy) than any of the magnums. That's not to say it's a good choice for long range or for big game.

An advantage of the 338 WM is that it's a mid-length cartridge 3.34"SAAMI OAL which is often sold in full length magnum 3.6" actions. That's very desirable for shooting heavy low drag bullets at moderate velocities.

I have rifles in 338 Federal, 338 WM, 338 Rum, and 338-378 Wby. My favorite is the 338WM in a SAKO TRG-S rifle. (3.6"_ magazine) My 338-378 is also a SAKO TRG-S, but it cannot feed cartridges loaded with heavy low drag bullets from the magazine, nor can the 338 RUM in a Rem 700LA. Both have obnoxious recoil and muzzle blast. The 338 Federal also is hopeless for shooting heavy ow drag bullets as it's a short (2.85") action. A 338 WSM or 338 SAUM would have the same problem as most are sold in short action rifles. .

Each of the above cartridges is a tradoff in several properties. Kind of like the Goldilocks story. Too much, too little, or a good tradeoff in all of its properties. The 338 WM is not the "best" in any one property including efficiency, but the best overall combination of properties in my opinion.

High efficiency isn't always the best choice. At moderate ranges lighter bullets at higher velocities may produce more reliable kills. The short action cartridges have their place too.

I'm curious why you (MSU Marksman) emphasize high efficiency over other properties which are desirable in a hunting cartridge such as a flatter trajectory and reduced wind deflection. I've never considered cartridge efficiency a goal in itself, only a result of trying to achieve particular exterior and terminal ballistic characteristics.

 

[Topshot]

The .338 NSS is your answer. (.338NelsonSambarSlayer)
It is a .338RUM shortened to hold 85 grains of powder.

Can get a 250 grain Hornady BTHP match bullet to 2850 - 2950fps out of a 26" barrel with minimal recoil.

Now all I have to do is build one?

 

[AZShooter]

I would like to hear more about the 338 NSS. Tried googling it, no listings.

The 338 Dakota or 338/375 Ruger are other considerations. They are very similar to each other. The 375 Ruger brass is less expensive. Both are larger than the 338 Win mag with same length case. You can read load data for the Dakota to get some idea of potential.

From what I can gather, based on published reloading data, the 338 win mag and the 338 Dakota are incapable of delivering 2800 fps with a 250 gr bullet. Perhaps with a 30" barrel the Dakota case could do it.

I would like to hear of members who have actually gotten a 250 gr bullet to go 2800 fps with a typical sporter length barrel and a 338 win mag.

 

[ridge rider]

The .338 NSS is your answer. (.338NelsonSambarSlayer)
It is a .338RUM shortened to hold 85 grains of powder.

Can get a 250 grain Hornady BTHP match bullet to 2850 - 2950fps out of a 26" barrel with minimal recoil.

Now all I have to do is build one?

Topshot,

What is the purpose of building this rifle. Is it for a lighter weight rifle with less recoil and no need for a muzzle brake..
Then if you are going for a lighter rifle and please correct me if I am wrong but from my knowledge the only actions that will handle the shortened Rem 338 Rum round (aka 338 NSS) are the very long actions and that defeats that purpose for a light weight rifle without muzzle brake.
My suggestion is:.............go for the Tikka T3 in 338WinMag.
It is a great combination and you will not get a better, more accurate out of the box rifle nor a more efficient round to produce what you may seek.

 

[ewallace]

I have a 330 dakota XP-100 with a Broughton 10 twist 18" barrel and it will push the 300g bullets 2544 fps here is a pic

I have not shot any 250g bullets in my dakota but have shot some 225g accubonds and am getting 2881 with them and a pic

and a pic of the XP-100 in 330 dakota

 

[Topshot]

Topshot,

What is the purpose of building this rifle. Is it for a lighter weight rifle with less recoil and no need for a muzzle brake..
Then if you are going for a lighter rifle and please correct me if I am wrong but from my knowledge the only actions that will handle the shortened Rem 338 Rum round (aka 338 NSS) are the very long actions and that defeats that purpose for a light weight rifle without muzzle brake.
My suggestion is:.............go for the Tikka T3 in 338WinMag.
It is a great combination and you will not get a better, more accurate out of the box rifle nor a more efficient round to produce what you may seek.

Ridge Rider..........

A good .338 calibre, 250 grain bullet @ 2900 fps offers serious long range performance.

The 404 Jeffery derived cases like the .330 Dakota and .338NSS are all good. Just decide on a cartridge with the powder capacity that suits your needs, slap in a bullet in your favorite calibre and away you go.
Add a muzzle brake and 26" match grade barrel and you have a rifle that is light enough to be carried anywhere and can also be shot with ease off hand.

The .338 Edge, RUM and Lapua etc offer better performance in rifles with a longer barrel. But in a light pack rifle with a 26" barrel, the difference in performance might not be significant. Recoil and noise however might be.

The Tikka T3 is a great rifle in .338WM as can be seen from recent results of Luke's rifle, both at the range and on game. But a couple of hundered extra fps would sure flatten the trajectory past 500 yards.