High performance 350 Remington Magnum
- Thread starter Slamfire
- Start date
- Location
- In the shadows of the Rockies
375 H&H Sako Kodiak vs. 350 RM SI
Curious to see what I could get for maximum 300gr bullet speed from my 375 Kodiak to compare with my 350 RM. Nosler data lists a maximum 375 load using Re15 as 68.0 gr / 2490 fps (24" barrel) for their 300gr AB. https://load-data.nosler.com/load-data/375-holland-holland-magnum/
So using 68.0 gr of Re15 with the Woodleigh 300gr PP SN bullet in my 375 Kodiak my chrony read 2443 fps (7.5m from the muzzle). Compared to 2436 fps for the 310gr bullet. Essentially the same. For a bullet that's 3% heavier and using 8% less powder. The efficiency of the medium bore short magnum.
375 H&H Magnum / 350 Rem. Mag. SI
Curious to see what I could get for maximum 300gr bullet speed from my 375 Kodiak to compare with my 350 RM. Nosler data lists a maximum 375 load using Re15 as 68.0 gr / 2490 fps (24" barrel) for their 300gr AB. https://load-data.nosler.com/load-data/375-holland-holland-magnum/
So using 68.0 gr of Re15 with the Woodleigh 300gr PP SN bullet in my 375 Kodiak my chrony read 2443 fps (7.5m from the muzzle). Compared to 2436 fps for the 310gr bullet. Essentially the same. For a bullet that's 3% heavier and using 8% less powder. The efficiency of the medium bore short magnum.
375 H&H Magnum / 350 Rem. Mag. SI
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It's difficult to understand the fascination with "efficiency", particularly for hunting rifles which in most cases are fired fewer than 1000 times by their present owner.
Powder costs less than a penny a grain, yet decisions are made on that basis.
Of course for a given bore diameter a smaller case will use less powder to reach the same MV as a larger case, but the larger case will always reach that same MV at a lower pressure. Most importantly, if pressure limits are to be respected, the larger case will be able to safely generate higher MV's.
We all know too about diminishing returns. The 22 LR can generate about 1500 fps with a tiny payload, the 223 can generate twice that with 10X the powder, and the 220 Swift less than three times that with almost 20X the powder. So if you only "need" 1500 fps, the most efficient choice is the 22LR, but what's the most efficient if you need 4000 fps?
Powder costs less than a penny a grain, yet decisions are made on that basis.
Of course for a given bore diameter a smaller case will use less powder to reach the same MV as a larger case, but the larger case will always reach that same MV at a lower pressure. Most importantly, if pressure limits are to be respected, the larger case will be able to safely generate higher MV's.
We all know too about diminishing returns. The 22 LR can generate about 1500 fps with a tiny payload, the 223 can generate twice that with 10X the powder, and the 220 Swift less than three times that with almost 20X the powder. So if you only "need" 1500 fps, the most efficient choice is the 22LR, but what's the most efficient if you need 4000 fps?
- Location
- In the shadows of the Rockies
Chamber pressures for both are likely ~60k psi. The never ending quest to do equal or more with less. The 350 RM sharp shoulder creates an abrupt increase in gas flow speed to increase bullet speed - the venturi effect.
Not the most efficient case design with its long taper and shallow shoulder, the 375 H&H was an appropriate design in the days of yore when strands of cordite was the propellant of choice. Only way to get enough in to produce high bullet speed was to design a long case without a bottle neck.
Not the most efficient case design with its long taper and shallow shoulder, the 375 H&H was an appropriate design in the days of yore when strands of cordite was the propellant of choice. Only way to get enough in to produce high bullet speed was to design a long case without a bottle neck.
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