338/300 Win MAg.

[300Ultra]

Has anyone necked up the 300 win mag to 338 and given it a longer neck? Maybe an A.I. shoulder angle? I searched 300 Win Mag wildcats and really didn't turn much up. Thanks all.

 

[2644ever]

I did it about 8 years ago, I just asked Dave Manson to alter a .338 Win Mag reamer by relocating the belt further in order to use .300 Win Mag brass. The benefits are a longer neck, a slightly wider shoulder and the availability of .338 WM dies. The project started with a 28" Douglas barrel and a Savage action.
This is a very efficient cartridge next to the .338 Lapua Mag: With Norma cases that hold about 95 grains of water after fireforming, 77.5 grains of N560 and Lapua's 250 Moly Scenar, you easily reach 2880 fps with a lot less recoil and barrel wear. I was so pleased by the accuracy and the ballistics I even chambered a 3 groove stainless PacNor because it was worth it, and several friends have borrowed my reamer...
I nickamed that wildcat the .338 Tora Bora because of the heavy pounding that place was receiving from B 52's at that time...

 

[300Ultra]

Cool 8). I'm not sure how the 338 Winny dies figure into it though. Isn't the finished round longer to the shoulder than the factory .338? If you could post a pic of the Tora Bora between a 300 Winchester and the 338 Winchester,that would be great. I guess what I was looking for is a souped up 338 with the same COL as the 300 Winchester to be fed in a standard length M70 magazine.

 

[wboggs]

I'm not sure why you want to go this route. A .338 Ultra will do everything the wildcat will and in fact equal the Lapua with a proper chamber and equal pressures at much less cost. My custom Ultra with a 26" krieger barrel gives 2980 fps with 250 gr. Barnes triple shocks using MRP and puts3 shots in 5/8" at 200 yds. It has been used in Africa to take over 100 animals and it really impressed the PHs.

 

[2644ever]

Cool 8). I'm not sure how the 338 Winny dies figure into it though. Isn't the finished round longer to the shoulder than the factory .338?

I use the elliptical expander of the Pacific .338 die to expand the neck of the .300 WM first, then I use the die itself to resize the formed case, leaving a .12" gap between shell holder and die base. You can also use Lee's Collet dies in .338 WM but you gotta glue washers to the die base.
I didn't intend to use Ultra Mag brass because it's more expensive and I wanted something more efficient than the Lapua cartridge, with off the shelf components (Dave was kind enough to move the belt on the reamer free of charge). Besides, neither the Lapua nor the UltraMag will fit in a standard Savage or Winchester magazine...
Here's a picture: .338 Tora Bora (center) .338 Win Mag (left) .338 Lapua Mag (right)
http://img689.imageshack.us/img689/6822/338torabora.jpg

 

[2644ever]

And I should add: The substantial increase in volume (10 grains of water) allows me to use N560 to its full potential. Had I stuck to the .338 Win Mag, I would have had no better option than N550 with a less favorable loading density. MRP is probably the best powder if you're not afraid of 103% loading densities, and I have yet to test Re22 and Accurate's Magpro which should be perfect in my opinion.

 

[buffybuster]

How about the .375Ruger necked down to .338.... a 338-375Ruger. That would be very close the a 338-300WM without the belt.

 

[2644ever]

You're right. If you don't already have .338 Win Mag reamer and dies, it's a very good option to upgrade a .338 Win Mag chambering.
http://savageshooters.com/SavageForum/index.php?topic=25670.0

 

[300Ultra]

Hey thanks for the pic and links 2644ever. Man they sure have taken the 338 caliber to new levels! I like that Tora Bora. You've got a dandy there. The 338-375 Ruger has a bunch to offer also. Cool stuff 8).

 

[2644ever]

Well, if one day you're ready to give it a try, I may lend you my reamer and 2 cases . You will gain time by having first the barrel chambered, headspaced for the .338 Win Mag and not screwed too tightly as you'll only have to ream about .12" deeper afterwards.

 

[300Ultra]

Well thank you 2644ever. That's a very generous offer 8). I'll keep it in mind should I decide to do one up.

 

[RustyPin]

Shazam! I Command You, Awake! I really love this Tora Bora, and thought about this one once again. It's just not worth the extra cost of the Ultra Brass to me when the 300WM Case can be the do everything Hunter. Will the standard Savage 338WM Action be long enough for the .338-300WM? I know it may not be a One Mile Cartridge for paper. I've even mastered turning 300RUM into the 33NOZ. Does the Reamer exist?

 

[DaveTooley]

338/300PRC
nuff said

 

[Jaybo]

Why not get a 340 weatherby or the 338 rum ?

 

[RustyPin]

No doubt both excellent cartridges. Cost is the deal here as the Wby & PRC are way more in price. I don't want to cry if I lose a Case out in Pines.

 

[dkhunt14]

Compared to the cost of building a custom chambered and barreled rifle verses losing a case, is peanuts. In all the years of hunting, I have lost very cases. Most times I never have to work the bolt again. I love the 338 for its killing ability, one shot and done. Matt

 

[RustyPin]

Compared to the cost of building a custom chambered and barreled rifle verses losing a case, is peanuts. In all the years of hunting, I have lost very cases. Most times I never have to work the bolt again. I love the 338 for its killing ability, one shot and done. Matt

Tru-Dat, only consideration would be Re-Chambering a factory .338 Win Mag.

 

[Greymatter762]

This cartridge and thread interests me too. I'd love to have more info on the 338-300 WM. The PRC variants are certainly more costly and components are hit and miss with availability since its release.

 

[Arctichound]

This cartridge and thread interests me too. I'd love to have more info on the 338-300 WM. The PRC variants are certainly more costly and components are hit and miss with availability since its release.

I built one back in 2018, it had a tikka T-3 action with a 25" pac-nor barrel. I built it for hunting, I was able to get the barnes 210 ttsx to shoot really well at 3135 fps. It shot a 4 round 2.13" group at 550 yards. I was able to get 225 ttsx to run at 3034fps and the 265LRX at 2826 fps. Without a lot of excessive pressures and close to .5 MOA. I don't think that's bad for a "hunting rifle.