If you have an AR10 styled rifle (DPMS) already in 308 are the 260 and 243 uppers worth buying? Really, I am just unfamiliar with the 243 and 260 cartridges and I don't know or understand what they can do 308 cannot. I would imagine the 243 might be a good varmint round? I also read alot about the 260 shooting flatter than the 308? But I wonder about BC and FPS with these 3 cartridges. I don't have a DPMS 308 yet but plan on getting one over the next year or so.
If you have a 308 in the AR platform are the 243 & 260 uppers worth getting?
- Thread starter Mags
- Start date
- Status
R.W.Dale
Member
If you're not a slave to factory ammo and don't already own the rifle I'd opt for the 260 or 7mm08.
That being said there isn't a darn thing any of these mentioned do that 308 won't do just as well.
That being said there isn't a darn thing any of these mentioned do that 308 won't do just as well.
krochus said:
For a hunting rifle I'd agree 100% and if I were only choosing one cartridge for a good all-around hunting rifle it'd be the .308 Win ... no doubt about it. However, competitive shooting is a little different and the .260 is the smart choice there. My F-Class F-T/R rifle is chambered in .308 Win but I'm building an F-Class F-O rifle in .260 Remington that will serve double duty as a practical shooting rifle too. There are significant ballistic advantages with the .260 Rem over the .308 Win when you stretch it out to 600, 800, 900 and 100 yards. There's also a reduction in recoil with the .260 Rem over the .308 Win which can make a big difference when trying to shoot into a 1/2 MOA X-ring at long range.
Last edited:
Zundfolge
Member
There are many who believe the .243 is the optimum deer hunting round.
R.W.Dale
Member
And I agree hence my comment that were I starting from scratch 260 would be my top choice.For a hunting rifle I'd agree 100% and if I were only choosing one cartridge for a good all-around hunting rifle it'd be the .308 Win ... no doubt about it. However, competitive shooting is a little different and the .260 is the smart choice there. My F-Class F-T/R rifle is chambered in .308 Win but I'm building an F-Class F-O rifle in .260 Remington that will serve double duty as a practical shooting rifle too. There are significant ballistic advantages with the .260 Rem over the .308 Win when you stretch it out to 600, 800, 900 and 100 yards. There's also a reduction in recoil with the .260 Rem over the .308 Win which can make a big difference when trying to shoot into a 1/2 MOA X-ring at long range.
Ramble mode ON
But there's also a tendancy in such threads to make slight ballistic advantages one cartridges might have out into insurmountable obsticles the other chamberings cannot overcome. Such cartridge choices are not simple yes and no questions but rather choices based on how the last few percentage points after the 95% of what's in common is added up.
JpSnareGuy
Member
.260 Rem or 6.5 CM ...
Float Pilot
Member
I have been pondering this same question: So I ran some numbers by my ballistics program.
1. Assume a AR-10 size rifle with a 20 inch barrel.
2. Next step figure which loads would represent the loads likely to be used and which are different enough from each other.
3. What is the real velocity obtained by those loads with a 20 inch barrel.
So I went with:
6mm (243 Win) using a 95 grain boat-tail bullet with a MV of 3,000 fps. 0.480 B.C.
6.5mm (260 Rem) using a 120 grain boat tail bullet at 2,800 fps, 0.450 BC
7.62mm (308 Win) using a 150 grain Boat tail at 2,650 fps,, 0.398 BC
All zeroed for 300 yards.
The 243 is 4.6 inch high at 175 yards when zeroed at 300.
the 260 is 5.5 inch high at 150 yards when zeroed at 300
the 308 is 6.5 inches high at 150 yards when zeroed at 300.
Remaining velocity at 500 yards:
243 = 2,100 fps
260 = 1.887 fps
308 = 1,670 fps
NOTE*** Bullets which have not been over stabilized are capable of tumbling upset type devastating wounds at impact velocities around 2,600 fps and above.
243 = 2,600 fps impact velocity at 200 yards
260 = 2,600 fps impact at 100 yards.
308 = 2,600 fps at 50 yards.
1. Assume a AR-10 size rifle with a 20 inch barrel.
2. Next step figure which loads would represent the loads likely to be used and which are different enough from each other.
3. What is the real velocity obtained by those loads with a 20 inch barrel.
So I went with:
6mm (243 Win) using a 95 grain boat-tail bullet with a MV of 3,000 fps. 0.480 B.C.
6.5mm (260 Rem) using a 120 grain boat tail bullet at 2,800 fps, 0.450 BC
7.62mm (308 Win) using a 150 grain Boat tail at 2,650 fps,, 0.398 BC
All zeroed for 300 yards.
The 243 is 4.6 inch high at 175 yards when zeroed at 300.
the 260 is 5.5 inch high at 150 yards when zeroed at 300
the 308 is 6.5 inches high at 150 yards when zeroed at 300.
Remaining velocity at 500 yards:
243 = 2,100 fps
260 = 1.887 fps
308 = 1,670 fps
NOTE*** Bullets which have not been over stabilized are capable of tumbling upset type devastating wounds at impact velocities around 2,600 fps and above.
243 = 2,600 fps impact velocity at 200 yards
260 = 2,600 fps impact at 100 yards.
308 = 2,600 fps at 50 yards.
- Status
