7 mm rem verses 7mm weatherby

[ann brezinski]

given same barrels why is the weatherby loaded hoter then the 7 mm Remington mag?if the chamber were the same for bullet free bore can you load the rem to same pressures/I see that there is about 50 to10 fps difference between them.
gary b
any thoughts on this.

 

[idaho elk hunter]

I commonly use the starting loads for the Weatherby and work up for the 7 mm Rem. The rifle must have freebore. I am currently building another 7mm mag with a Broughton 28 in nitride barrel, using 175 ABLR ,Hex coated, seated to 3.5 coal. Using Winchester brass and Winchester Mag primers. Hoping to get 3125 to 3150 fps.


THE ONLY REASON THEY MAKE 30 CALS IS TO MAKE THE 7MM LOOK GOOD!

 

[HARPERC]

It's been a long time since I loaded for these 2. The only online source I found the 7mm Remington (W-W brass) listed to have 83 grains capacity, and the 7mm Weatherby to have 87 grains capacity. Presumably H2O, but I didn't dig deep.

That seemed consistent with what I recall. All things being equal the Weatherby should yield about 1-2% more velocity. Things are rarely equal, as Weatherby came in 26" barrels, compared side by side to 24" barrels adds little to the gap between them.

The Weatherby used to come with twist of 1-12", and may not stabilize the heavier longer bullets out there. The one I shot would key hole the old "Barnes Original" 195 grain bullets. The Remington (Ruger rifle) would shoot them without issue.

 

[Ridgerunner665]

given same barrels why is the weatherby loaded hoter then the 7 mm Remington mag?
any thoughts on this.

Because the 7mm Rem Mag is prone to pressure swings of up to around +12,000 psi with some load combo's...there are other rounds that suffer this too, the 243 Win being one of them.

There has been a lot of time invested in "why" the pressure swings happen...no clear answer that I'm aware of...but they do happen.

 

[MudRunner2005]

I commonly use the starting loads for the Weatherby and work up for the 7 mm Rem. The rifle must have freebore. I am currently building another 7mm mag with a Broughton 28 in nitride barrel, using 175 ABLR ,Hex coated, seated to 3.5 coal. Using Winchester brass and Winchester Mag primers. Hoping to get 3125 to 3150 fps.


THE ONLY REASON THEY MAKE 30 CALS IS TO MAKE THE 7MM LOOK GOOD!

I'm getting 3115 out of my 7mm RM with 168 VLD's in a 26" barrel. You should easily be able to get 3150 out of a 28".

 

[Lefty7mmstw]

saami max is also lower on the 7rem.... 61,000psi vs. 65,000 psi for the roy. I've not been a fan of pushing little 7mm's like the 7rem; they will hit the wall in a hurry if you try. I'll loaf a bigger 7mm and get better speed and bore life than pushing a 7rem.

If you like the 7rem, go for it, but I'd rather buy a 280 or 280ai if I want a milder 7mm as they will do nearly what a 7rem will do and they are more efficient. As to 171-175 grain bullet speeds in the bigger 7mm's; I'll toss them in my 7rum and get 3150 fps with start loads using retumbo. I haven't even played with good powders yet. I'm thinking of switching to rl50 or 50bmg to see what she'll really do.