Why is there such a large variation in the ballistics of factory loaded 6.5x55?

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Northern Shooter

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I'm currently trying to pick out the right 6.5x55 ammo to use on the moose hunt this year. So far all I've been able to source near me are the S&B 140gr and 156gr soft points as well as the 139 SP from PPU.

Looking at the ballistics of each they all appear to be fairly light in the energy department.


S&B 156 gr - 1,947 ft-lb
PPU 139 gr - 1995 ft-lb
S&B 140 gr - 2,110 ft-lb

I then started looking at offerings from Nosler, Lapua and Norma and they present a different story, especially the Norma.

Nosler - 140 gr Accubond - 2,182 ft-lb
Lapua 156 gr Mega - 2,254 ft-lb
Norma 156gr Oryx - 3,072 ft-lb

I still need to cross shop the offerings from Remington/Federal/Winchester but I doubt they will match the performance of the Norma.

How is the Norma Oryx producing so much more energy? It produces more energy at 200m than most of the other cartridges do at the muzzle.

Is it just bullet design? high B/C?

Unfortunately I can't seem to find these Norma 6.5x55 anywhere in Canada.
 
Energy delivery calculation has nothing to do with bullet construction, it has everything to do with mass and velocity (Obviously bullet construction will have an effect on how much energy is expended when the bullet hits the target, but that's a different thing). Both the Lapua and Norma 156 grain loads are rated at 780m/s. Their energy at the muzzle will be identical. Something is wrong with your data/numbers.

Edit:
MiG25 said:
Because the 3072 is Joules mislabeled as Ft-lbs.
Click to expand...

That's what's wrong, lol.
 
I have found that some factory loads for 6.5x55 are fairly light due to the large number of surplus rifles that are still around. These may not be as safe with the same loads as newer rifles.

Much like the .45/70 factory loads, usually quite anemic compared to the Marlin and Ruger rated loadings.

Liability.
 
European ammo is probably not 6.5x55mm Swedish but rather 6.5x55 SE, they are different pressures, essentially a +P.

For old Krag rifles the 6.5x55 SE would be a bad idea, for the mausers it would depend but the idea of the SE is for modern actions for the most part.

You say that the energy is low but when you look at the calculators you are looking at over 800ft lbs past 500 yards with these standard flat base 140gr bullets, 1200 ft lbs past 300 yards.
 
Fox said:
European ammo is probably not 6.5x55mm Swedish but rather 6.5x55 SE, they are different pressures, essentially a +P.

For old Krag rifles the 6.5x55 SE would be a bad idea, for the mausers it would depend but the idea of the SE is for modern actions for the most part.

You say that the energy is low but when you look at the calculators you are looking at over 800ft lbs past 500 yards with these standard flat base 140gr bullets, 1200 ft lbs past 300 yards.
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That's good to know regarding SE vs Swedish, I've never heard of that distinction before. As for energy I'm trying to keep it above the recommend 1500 ft-lb for moose which limits me to 200 yard shots which is what I was planning to do anyway.
 
Northern Shooter said:
That's good to know regarding SE vs Swedish, I've never heard of that distinction before. As for energy I'm trying to keep it above the recommend 1500 ft-lb for moose which limits me to 200 yard shots which is what I was planning to do anyway.
Click to expand...

I used to be told that the "minimum energy to kill a deer was 100 ft lbs", then I shot one with a 50 cal patched round ball gun and realized how crazy that is.

They have been shooting moose with the 6.5x55mm cartridge since it came to be, the 160gr bullet has an amazing sectional density, it will drill a hole, using factory ammo you will be fine.
 
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