7mm on the 300 weatherby

[ann brezinski]

I saw this on other forums.any thoughts on loads for this?
an y one using this round and would like to talk about it.
gary b

 

[WildRose]

I knew some guys shooting it back in the late eighties/early nineties. They loved the velocity because it made for a very flat shooter but barrel live was short and they had a bad time with bullets just blowing up instead of expanding properly.

With roughly 102gr of case capacity it's way overbore.

Because of the double radius shoulder of the Wby though throat erosion isn't quite as bad as it would be with 7mm Rum and similar cases.

I considered both the 7mm x .300wm and 7mm x .300wby when looking for more velocity than I was getting with the 7mm Rem and looked at both hard but in the end settled on the 7mm STW.

 

[AZShooter]

Based on case capacity of the 300 weatherby and the 8mm mag these two are 99 and 98 respectively. link to capacities:Case Capacities That would mean a 7mm/300 weatherby and the 7 STW would be ballistic twins.

If you already own the 300 weatherby redding bushing/ body / FL die sets you could use them to work with the 7mm quite easily. Only other reason I can think of for using the weatherby version would be brass availability. And perhaps the cool double radius shoulder.

I doubt many gunsmiths would have the reamer so that would be an additional cost. But you could get the reamer made to your specs.

 

[drags]

Based on case capacity of the 300 weatherby and the 8mm mag these two are 99 and 98 respectively. link to capacities:Case Capacities That would mean a 7mm/300 weatherby and the 7 STW would be ballistic twins.

If you already own the 300 weatherby redding bushing/ body / FL die sets you could use them to work with the 7mm quite easily. Only other reason I can think of for using the weatherby version would be brass availability. And perhaps the cool double radius shoulder.

I doubt many gunsmiths would have the reamer so that would be an additional cost. But you could get the reamer made to your specs.

I have had a 7x300 wby and I consider it a very good cartridge, the only negative was that case life was short but could be extended through annealing. As for gunsmiths having a reamer, if you check some of the gunsmiths in north central Pa. Mark King, Bob Wolfe, Eric Springman and others you will find that most have 7x300 wby reamers, the 7x300 originated in the north central Pa. area invented by Howard Wolfe. I formed cases using norma or weatherby brass and redding 7x300 wby dies (non bushing) these dies are readily available from redding and I think rcbs also makes these dies, you don't need to use dies from other calibers to form the brass just buy the redding or rcbs dies and you are good to go. The redding offers a 3 dies FL, neck, and seater die for the 7x300.
Joe

 

[shooter72]

I had one a long time ago, very good shooter but never could get as much out of it as I thought I should. It is interesting though.

 

[4xforfun]

As far as I know, the STW and the 7-300 WBY are clones, performance wise. I used 7 STW starting loads and went from there on the one I worked on. No work to make the brass....simply run 300 brass through your die with the smaller bushing.

I am going to build one someday since I have a large supply of 300 WBY brass already and can use my Redding 300 Wby dies with different bushings. Should be a monster with the new Berger 195's!!!

Good luck,
Tod

 

[ann brezinski]

I found a used 7mm/300 weatherby for 1250 with a 6 to20 leapold scope on it I also understand it has about 350 rounds through it .barrel is a shilen at 27 in long on a 721 actionand has a muzzle brake on it.i have about 100 rounds of 300 weatherby brass.
what are your thoughts on this?
gary b

 

[Lefty7mmstw]

if you like the condition of the rifle and the price seems right to you, go for it. I think the 7x300 may make inroads to the large 7mm market the way everyone is neglecting making brass for the stw and rum... it can be flat out hard to find brass for those at times and not everyone will fireform brass... the 300roy brass always seems to be available in one brand or another...
as said earlier, the load data is similar enough to 7stw data that you could likely run it up from stw start loads...

 

[drags]

We used weatherby or norma brass (probaly the same thing) we tried rem. brass but case life was short and the wby and norma brass would take hotter loads, on one occasion a load with the wby brass was fine but the same load with the rem. brass blew a primer. If the 300 wby brass was new we neck sized and fire formed, also we fire formed with a liter load. To increase case life we also annealed. The liter weight bullets are supposed to harder on barrel's according to Howard Wolfe the inventor of the 7x300 wby and we always used 162 or 168 gr. bullets.
Joe

 

[Cuz]

I have been shooting one for a few years now. Ever since 7stw brass started drying up. 180 berger hybrid at 3100 with imr 7828 fairly mild load. Very accurate. 300 weatherby brass is plentiful and it is a ballistic twin to the stw. I think it ranks right up there with the best of the 7mm cartridges.

 

[drags]

I have been shooting one for a few years now. Ever since 7stw brass started drying up. 180 berger hybrid at 3100 with imr 7828 fairly mild load. Very accurate. 300 weatherby brass is plentiful and it is a ballistic twin to the stw. I think it ranks right up there with the best of the 7mm cartridges.

Maybe wby will come out with 7x300 wby brass like they did with 6.5x300 wby brass if so that would really put the 7x300 wby on the map.
Joe

 

[longrangebo]

I had 2 of them, one built on Rem. the other Sako. Like another poster said the go to gun in the 70-80-90,s We killed many deer with them. Sold one in 99 the other about 2 years ago . They both liked the 162 Hornady or the 168 Matchking Back then was using H8670 or h4831 Lots of my friends used them as well. The brass is just 300 Wby. run through 7x300 die. The dies are still used by many smiths here.Baer, Wolfe, Goodling amd King!

 

[4xforfun]

Maybe wby will come out with 7x300 wby brass like they did with 6.5x300 wby brass if so that would really put the 7x300 wby on the map.
Joe

With 300 wby all ready available and with the 6.5 WBY up and comming, why would you even care if there is 7-300 brass? It takes about 3 seconds to make one.

Just sayin.

 

[drags]

With 300 wby all ready available and with the 6.5 WBY up and comming, why would you even care if there is 7-300 brass? It takes about 3 seconds to make one.

Just sayin.

When forming cases from another caliber I believe they should be fire formed with a slightly milder load, by doing this you get longer case life and better accuracy. This was told to me personally by Howard Wolfe the gunsmith and inventor of the 7x300 wby.
Joe