7mm-300 winmag

[hogslayer]

I am in the process of a new build chambered in a high performance 7mm round. I would like to know if any of you out there have any real world experience with this cartridge, I will be shooting 162 grn amax for varmints and 180 grain berger for big game. I believe that I could achieve 7stw velocitys with less powder and also be able to seat the vlds out to the lands and still fit in the magazine.

 

[Michael Eichele]

The 300 winnie and the 7mm Rem mag cases are VERY close in design. It is alot of headache and expense to go with a wild cat that offers such little performance gains IF any over a readily available cartridge. If you want a 7mm wild cat, dont joke around. Use a bigger case.

 

[Limbic]

My seven mag will pust 180g Bergers at 2950-2970fps. It works for me because the bullet specturm is what I need. It is hard to increase velocity without increasing powder or using harder brass.

I'd get the STW.

 

[LRHWAL]

You may search for the .280 or .284 Jarrett (or 7mm Jarrett?) - I think that was basically what he designed using the 300 WM case. He claimed it was very efficient as I recall.

 

[Long Time Long Ranger]

Michael E is right on the money with his advice. Why not just get a 7mm STW and outperform what you will go through quite a bit of trouble to build. I have shot the 7mm-300 wby and the now named 7mm STW since the mid 70's and they are great 7mm's that will outperform what you are looking at. The 7mm-300 ultramags I did just went through barrels to quick but were very good long rangers with heavy bullets such as the 200 grain Wildcat and 180 Bergers. I decided from a lot of testing the 7mm-300 wby and the 7STW were about the best it got in 7mm before barrel wear got to be to much of a factor.

 

[distantfoe]

Up until the loss of 300win Lapua and RWS brass, I had considered a wildcat similar to this. Check out this write-up on the 284 jarrett, pretty much dups stw velocities with less powder. With the strong brass it could of been something.

http://www.jarrettrifles.com/calibers.html

 

[LRHWAL]

Distantfoe,

I thought RWS Brass was still available in 300 WM. I do see Huntingtons no longer stocks them. Is that the end of it?

WL

 

[grit]

7mm Dakota

 

[AZShooter]

You could neck down the 375 Ruger to 7 mm. Dave Kiff said that he had many requests for that reamer when the 375 Ruger first came out. It would be similar to the 7 Dakota with lower brass costs.

FYI I have a 30" 7 rem mag that gets 3100 fps with the 180 Berger VLDs. 69 grs of RL-25.

 

[Nomosendero]

I read the Jarrett info & if it is true, it is very impressive. They say it is very close if not duplicates the STW, I would think that with the 180 Berger or heavier & slowest powders the STW would pull away, but maybe I'm wrong. Does anyone know the case cap of the 375 Ruger case & how it compares to the 300WM?

 

[AJ Peacock]

I read the Jarrett info & if it is true, it is very impressive. They say it is very close if not duplicates the STW, I would think that with the 180 Berger or heavier & slowest powders the STW would pull away, but maybe I'm wrong. Does anyone know the case cap of the 375 Ruger case & how it compares to the 300WM?

According to Quickload, the 375 Ruger holds 99gr of water, the 300WM holds 88-95.5 depending on brass. Quickload lists 300WM (W), 300WM (N), 300WM (R), 300WM (F), 300WM (@). It shows 300WM (N) as 95.5 and 300WM(R) as 88, the other are in between.

AJ

 

[Nomosendero]

Thanks!