What cartridge for high speed 30 caliber

[jlann]

I am going to build a 30 caliber that can push a 230 Berger 3300. I was thinking of a 30-338 lapua improved. Don't know about the accuracy of this case at that speed if it can even get there. Looking at a benchmark barrel 3 groove 30" long. Looking for a single shot action to build on too. Please let know what you know or what case you would do and why.
Thanks Jack

 

[TXAoudadKlr]

I have a 300-338LMI. Mine is more in a big game hunting configuration. I'm leaving some throttle on the table with the 26" barrel. I've had 181's just shy of 3600fps, 200's at 3420. I never chronographed the 230's. Accuracy was always there 1/2 moa or better at the end often better.

If you want the biggest and baddest there is
the 300 Raptor/300HCM/300 LRO magnum all more or less the same using a long 338 Lapua case.

The 300 Terminator is a good candidate it's a 300LMI but throated differently

I have a Raptor coming with a 34" barrel btw.

 

[budlight]

You will really be close with a 30-378 with about 120 gr. of US869. But I got so tired of ruining cases after a few shots. The belts leaked and sometimes the necks cracked even with careful annealing. I originally bought a few hundred cases and by the time I had it dialed in and a few meets I had a bucket of bad brass

 

[IdahoCTD]

I have a 33" 30-338 Lapua Imp that is up there running 230's at 3350fps. I dont think you'll make it to 3300 with a 30". If I had to go faster I would do a 30XC. The brass for the XC is made by Petersons versus Bertram for the other long Lapua cases. I think I would focus on the 245's instead of the 230's. The additional mass will be helpful on game going that fast and the added BC doesnt hurt.

 

[TheFishBox]

If it was me I would wait to see how broz does with his 30 LRO testing if you really want the biggest and baddest. Personally though I have been thinking a guy needs to look closer at the bullet/powder combo you want and then figure out what case is going to work the best for you. Some of these truly large wildcats are going to force you to use ball powders which tend to be a bit on the finicky side and don't have great temp sensitivity, if this is something you are ok with messing around with then go for it.

 

[HARPERC]

......If it was me I would wait to see how broz does with his 30 LRO testing if you really want the biggest and baddest.......Personally though I have been thinking a guy needs to look closer at the bullet/powder combo you want and then figure out what case is going to work the best for you..

It seems lately there's always another .30 to check out.

 

[budlight]

Could someone list the case volumes in powder for these? I remember 15 years again Allen magnums had a big line of calibers

30-378 = I could get 124 C in mine. I met a competitor once with an improved that said he gained 6 grains more

300 Raptor
300HCM
300 LRO magnum
300 Terminator
300LMI
30XC

 

[TXAoudadKlr]

You could always neck a 338 Enablr down.

 

[IdahoCTD]

I have a .30-378 Imp too and it has considerably more case capacity then a Lapua Imp but the cases are super soft and only last 2-3 firings throttled back. I shot 210 Bergers 3500fps and 150 Ballistic Tips over 4000fps.

The slower VV stick powders work for the oversized cases so you dont need ball powders. I shot WC872 ball powder in my 30-378 Imp because it was the slowest powder available in the 90's when I built it.

 

[Wedgy]

Whatever you choose make sure you have good brass or you won't want to shoot it.

 

[TH]

I had a 300 Thunderhulk. It was a 408 Case shortened and necked down to the same dimensions as the 300 Norma Mag with an improved shoulder. My rifle had a 33 inch barrel. I was able to push a 215 Berger over 3600 FPS with H1000. My accuracy load I was shooting 3578 FPS. I also tested the 230 Berger and was able to shoot that over 3400 FPS. I only tested this rifle to 1 mile but what I will say is the 215 in my rifle was flatter and more accurate at 1 mile than the 230s. There are lots of good bullets out there but there comes to a point that you really don't need to shoot the heaviest highest BC bullets out there how far do you really want to shoot? Another thing you want to look at is.......you do want to run an efficient case where there isn't a lot of extra case space because there really isn't a lot of really slow temp stable powders out there to choose from.

 

[J E Custom]

What you will need is a cartridge that will hold lots of powder and a barrel long enough to burn all that powder.

I would recommend a 30/378 Weatherby cartridge In front of a strong action like the Mark 5, and a heavy straight tapered 30+" barrel. you can shoot the cases once and size only enough to use the shoulder to head space on instead of the belt to save the brass.

If you improve the 30/378 case powder volume can be increased to around 140 grain powder capacity.

The 30 x 338 Lapua improved is a great cartridge but the powder capacity will not compare to the 378's so if velocity is what you want, it would be a good choice in my opinion.

J E CUSTOM

 

[COmtnman1]

What you will need is a cartridge that will hold lots of powder and a barrel long enough to burn all that powder.

I would recommend a 30/378 Weatherby cartridge In front of a strong action like the Mark 5, and a heavy straight tapered 30+" barrel. you can shoot the cases once and size only enough to use the shoulder to head space on instead of the belt to save the brass.

If you improve the 30/378 case powder volume can be increased to around 140 grain powder capacity.

The 30 x 338 Lapua improved is a great cartridge but the powder capacity will not compare to the 378's so if velocity is what you want, it would be a good choice in my opinion.

J E CUSTOM

what exactly is a 30-378 improved? i'm kind of ignorant i guess

 

[IdahoCTD]

A 30-378 Weatherby with less taper plus the shoulder changed to 35 degrees and moved forward in my case. They have a lot of case capacity but the brass is junk. One warm load and the primer pockets are loose or gone.

I would do one of the long Lapua cases instead.