Thread: 6.5x55 SE Sanity Check

Hi, I just getting started loading for a 6.5x55 SE but I'm having doubts about some of the load data.

I will be using 129gr Interlock SP to start with and ADI AR2209 and AR2213SC powder.

The problem is determining a maximum load. Looking at ADI's data, it's significantly under pressure. ADI list maximum pressure as 46,000CUP (~51,000psi). CIP list the maximum pressure as 55,1100psi, an 8% increase.
ADI 129gr Interlock SP:
2209 45.5gr
2213SC 48.5gr

For comparison sake I had a look at Alliant's Reloader 19 and 22 data. For the commercial action the maximum pressure is listed at 58,000psi (+13.7%).
Alliant 120gr Speer SP:
RL19 @ 51,000psi 41gr
RL19 @ 58,000psi 46gr +12.2%
RL22 @ 51,000psi 42gr
RL22 @ 58,000psi 46gr +9.5%

2209 and RL19 have a similar burn rate as do 2213SC and RL22. Is it sane to think an 8% increase 2209 (49.1gr) and 5% increase to the 2213SC (52.4gr) will result in a pressure around 55,000, but still be below 58,000psi?

Any help would be greatly appreciated.

ADI and a lot of other powder makers/ distributors will quote low loadings because there still exists a lot of older pre 98 mausers. I don't load for a 6.5x55 anymore but when I did the top ADI load was generally the starting point if that helps. What rifle are you loading for?

A modern action Sako. It's more of a question of how high is too high. I don't want to hamstring the cartridge but also don't want to get caught up chasing velocity.

Originally Posted by Magnetite

5% increase to the 2213SC (52.4gr)

That should be 50.9gr.

I load 46-47 gn of 2209 behind the hornady 129 in my R8 for about 2800 fps. No pressure signs but warmish. Each rifle is different. Find the answer for your rifle load a ladder series from 44 up and look for pressure signs and accuracy nodes.

Chase accuracy not speed, that's what the swede is famed for, anything over 2600 fps will be perfectly adequate for hunting out to 3-400 ydswith that bullet. I use 2206h in my m38 sporterised with 140 gr Sierra gamekings 36 grains and 2550 fps predictable and reliable.

Increase powder charge by 0.5 for each load. Shoot a 3 shot group working your way up, rem bering to let your barrel cool down between groups. Take note of the accuracy, you should hit a sweet spot where your groups tighten up well before you reach any pressure signs.
As said above chase accuracy not speed.

FWIW I use 2209 in my Tikka and my collection of old SE’s. For the modern rifle, a tad under 45 grains behind 143 eldx pills prices 2770 fps with one hole at 100m. 139 Scenar with 41.5 gr of powder produces similar.

In the old rifles, I play with loads between 39 gr to just short of mid 40s. Velocity in the 2200 - 2500 range from memory. You don’t need huge amounts of powder to make this calibre sing.

Originally Posted by Magnetite

Hi, I just getting started loading for a 6.5x55 SE but I'm having doubts about some of the load data.

I will be using 129gr Interlock SP to start with and ADI AR2209 and AR2213SC powder.

The problem is determining a maximum load. Looking at ADI's data, it's significantly under pressure. ADI list maximum pressure as 46,000CUP (~51,000psi). CIP list the maximum pressure as 55,1100psi, an 8% increase.
ADI 129gr Interlock SP:
2209 45.5gr
2213SC 48.5gr

For comparison sake I had a look at Alliant's Reloader 19 and 22 data. For the commercial action the maximum pressure is listed at 58,000psi (+13.7%).
Alliant 120gr Speer SP:
RL19 @ 51,000psi 41gr
RL19 @ 58,000psi 46gr +12.2%
RL22 @ 51,000psi 42gr
RL22 @ 58,000psi 46gr +9.5%

2209 and RL19 have a similar burn rate as do 2213SC and RL22. Is it sane to think an 8% increase 2209 (49.1gr) and 5% increase to the 2213SC (52.4gr) will result in a pressure around 55,000, but still be below 58,000psi?

Any help would be greatly appreciated.

The Hodgdon data is quite old and current AR2209 is much faster. 45.5 grains of current AR2209 gave me 2805 fps and 46 grains 2,850 fps with the 129 grain in my T3. The higher load appears to be close to or at max to me. Loads with the old AR2209 matched the Hodgdon data. AR2213SC is a bit slow for the 120 and 129 grain but works better with the 140 and 143 grain projectiles. I was using the 129 grain Hornady SST and would not use the above loads with the Nosler AB and especially not with the Barnes projectiles. There is a thread further back discussing the 129 grain loads and I wrote an article for NZ Guns recently dealing with the 120 grain.
As you have discovered the 6.5 x 55 data is all over the map but would suggest that your two suggested loads are far too high. Working up to .260 Remington velocities (a slightly smaller case) would be a good way to go.
Regards Grandpamac.

its a very forgiving case. Step up gradually and it wont give you sudden surprises. Norma brass is softer than Lapua and will stamp mark sooner.

With its high BC and SD it neither needs speed or fancy bullets to perform well.

Thanks for all the replies.

Originally Posted by grandpamac

The Hodgdon data is quite old and current AR2209 is much faster. 45.5 grains of current AR2209 gave me 2805 fps and 46 grains 2,850 fps with the 129 grain in my T3. The higher load appears to be close to or at max to me. Loads with the old AR2209 matched the Hodgdon data. AR2213SC is a bit slow for the 120 and 129 grain but works better with the 140 and 143 grain projectiles. I was using the 129 grain Hornady SST and would not use the above loads with the Nosler AB and especially not with the Barnes projectiles. There is a thread further back discussing the 129 grain loads and I wrote an article for NZ Guns recently dealing with the 120 grain.
As you have discovered the 6.5 x 55 data is all over the map but would suggest that your two suggested loads are far too high. Working up to .260 Remington velocities (a slightly smaller case) would be a good way to go.
Regards Grandpamac.

Its seems the only place to get up to data data is Alliant and Vihta Vouri. I bought the Hornady 10th edition data and was sorely disappointed. As for ADI/Hodgdon the last update was in 2000.
ADI 1996 129gr:
2209 46gr @ 2800fps w/ 18" barrel
2213 47gr @ 2800fps w/ 18" barrel

ADI 2000 129gr:
2209 45.5gr @ 2703fps w/ 24" barrel
2213SC 48.0gr @ 2689fps w/ 24" barrel

Was this the 129gr thread you were referring to? https://www.nzhuntingandshooting.co....estions-25692/

Would the best bet be running off velocity instead. Killing testing at a maximum velocity of 2900fps w/ 23" barrel for the 129gr provided there are no pressure signs prior?

Also what length barrel is your T3?

Originally Posted by Tahr

Norma brass is softer than Lapua and will stamp mark sooner.

I'm using once fired Norma (from the same rifle) to start with. Even though it's softer does it make any practical difference?

Just start at adi max data or creep up a little from 260rem data as has been suggested. All will be sweet

I had a look at how pressure and velocity increase in relation to charge weight in both the 260 and 6.5x55. Looks my initial figures where too high. Assuming a linear relationship (I know it's not but there's only two data points) and target pressure of 58,000psi (the same as the 260).
New maximum charges:
2209 47.5gr @ ~2800 w/ 24" barrel
2213SC 50.5gr @ ~2800 w/ 24" barrel

I will be reducing them by 10% and working up in 0.5gr increments.

Sounds about right. What's the rifle? I've a Ruger 260 and a husky 1640 6.5 on the way.

Greetings Magnetite,
I have replied to my own thread so you should find it on page 1 now. Extrapolating from my own results with a standard T3 Lite barrel (570 mm I think) 47.5 grains of AR2209 would give you about 2,900 fps with the 129 grain and is likely too hot. I chronographed 50 grains of AR2213SC behind the 129 grain at 2,800 fps so 50.5 grains should give you about 2,830 fps. The 1996 data you quote appeared in their pamphlet in 1986 and the AR2209 in 1984.
Regards Grandpamac.

I finally found a place to do some testing.

I've only tested the 2209 so far. I stopped at 45.5gr which was doing 2842fps from a 580mm barrel with suppressor. This matches up with the ADI max load and .260 Rem speeds. If anyone's interested here's the results (4 shots each charge):

Grains fps SD ES
42.5 2693 23.3 52
43.0 2726 12.6 28
43.5 2750 10.4 19 (only 3 shots)
44.0 2761 16.8 39
44.5 2780 9.9 24
45.0 2805 9.5 22
45.5 2842 21.8 43

~43.3gr and ~44.8gr will be worth looking at. I'm not sure if it's worthwhile testing lower loads. I didn't get any pressure signs but it seems like testing higher loads would be asking for trouble. Thanks everyone's suggestions.