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Discussion Starter · #1 · (Edited)
i started testing loads for the 6.8 i thought some of you might be interested in results i had using WC 846 powder with 120 SST's. The results below are based on one shot as far as velocity until i got close to my goal of 2600 then i went to three shots. i measured the base with a blade caliber before and after and recorded any changes. Its not a digital so i did the best i could.

Rifle: 20" ARP TC
Optic: Bushnell 6400 Elite
Chrono: Magneto Speed Sporter
Powder: WC 846
Primer: WSR
Brass: Federal multi-fired
COAL: 2.255
Bullet: 120 SST

Shot # FPS
1. 24.0, 2100
2. 24.5, 2157
3. 25.0, 2195
4. 25.5, 2267
5. 26.0, 2302
6. 26.5, 2356
7. 27.0, 2387
8. 27.5, 2434
9. 28.0, 2525
10. 28.5, 2584
11. 29.0, 2585 (chrono issue maybe?)
12. 29.5, 2607
13. 30.0, 2603 (Absolute max)
I started see case dimension change at 28.5 from .0418 before firing to .0419.
At 30.0 dimensions went from .04185 to .0420 again it's a analog not digital so i just had to read it the best i could.
I then went on to test 3 shots of the loading that yielded close to 2600 fps
28.5
Av. 2466
High:2486
Low: 2448
SD: 15
ES: 38

29.0
AV. 2578
High: 2590
Low: 2555
SD: 20
ES: 35

29.5
Av. 2600
High: 2626
Low: 2576
for some reason i don't have the SD or ES written down,

Grouping came next with the following being the best of the bunch 3 shots were fired.
28.0 2525 fps gave .965 MOA
28.5 2466 fps gave .680 MOA (for some reason this gave less velocity than 28.0?)
29.5 2600 fps gave .1.230 MOA
Since i achieved 2600 fps in a 20" i shot the same load in my 18" Bison and lost 100 FPS.

My conclusion is,,, one could use this powder in a pinch with this bullet but it loses fps quickly in short bbls. Accuracy isn't the best at 2600fps but is really good 2500ish. But many other powders will yield this velocity so why bother? But if you happen to have a boat load of this powder it CAN be used. i did try 3 shots with a 110 gr. OTM but velocity was low and accuracy was bad. i could do some testing for grins and see what i come up with.
 

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Just curious as to what burn rate you think your surplus WC-846 might be?...

I am pretty sure it is in the 332/335 ballpark...

I am a bit amazed at the 30-grain charge. I would think it would be much over maximum...

I shoot plenty of the WC-844 and I know others that shoot much of the WC-846, but none in the 6.8mm SPC...

Good-luck...BCB
 

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Discussion Starter · #3 ·
Just curious as to what burn rate you think your surplus WC-846 might be?...

I am pretty sure it is in the 332/335 ballpark...

I am a bit amazed at the 30-grain charge. I would think it would be much over maximum...

I shoot plenty of the WC-844 and I know others that shoot much of the WC-846, but none in the 6.8mm SPC...

Good-luck...BCB
i agree on the 335 ballpark burn rate and to be honest, different lots of the WC-846 would produce different results. one might be able to load 31 grains, or only 28 grains. it is certainly a work up thing. i'm not going to use it there is no need at this point, i just thought others might find it interesting. i wouldn't be afraid to load 28 to 28.5 and that loading seems ideal with the lot i have but like i said other powders better suited would produce the same results.
 

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i agree on the 335 ballpark burn rate and to be honest, different lots of the WC-846 would produce different results. one might be able to load 31 grains, or only 28 grains. it is certainly a work up thing. i'm not going to use it there is no need at this point, i just thought others might find it interesting. i wouldn't be afraid to load 28 to 28.5 and that loading seems ideal with the lot i have but like i said other powders better suited would produce the same results.
From what I could find it is the same as BLC2.
 

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Discussion Starter · #5 · (Edited)
WC-846 re-test

i shot again using Wassman's and Constructors recommendations and here are the results. i originally used Fed cases because I've read they are the least forgiving and i wanted to see pressure signs quickly. For this test i switched to Rem cases and FED LRM primers and shooting the 120 SST again. i only tested 4 loading's of 3 shots at 100yds. I also shot 115 gr. as per Constructors recommendations.
Powder: WC-846
28.5 Best of the bunch.
COAL: 2.295
Ave-2547fps
H-2554
L-2543
SD-5
ES-11
group size: .80

29.0 Not sure what happened with this group. it stitched the first 2 rounds and the third hit way right, i didn't think it was that bad of a shot. i may have to retest it.
Av- 2582
H-2611
L-2566
SD-24
ES-45
group size: 1.92

29.5 a more concentric group but nothing special in the accuracy department.
Av-2612
H-2623
L-2606
SD-9
ES-17
group size: 1.24

29.8
Av-2618
H-2641
L-2592
ES-49
SD-24
group size: 1.38

i did shoot 2 groups of 3 with 115 FMJ's (Pulled Fed. Eagle bullets)
29.0
Av-2539
H-2541
L-2539
SD-1
ES-2
group size: 1.20

30.0
Av- 2637
H-2640
L-2634
SD-3
ES-6
group size: 1.45

any feed back appreciated.
 

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I still maintain that it has a burn rate somewhere between H-332 on the faster side and H-335 on the slower side...

BL-C(2) is considerably slower...

I never can get velocities near what seem to always be printed on this site and I am shooting from a 24 inch barrel...

My lot of WC-844 (I know, we are talking about 846) is about 1 grain slower than my keg of H-335...

Oh well, it is what it is I suppose...

Good-luck...BCB
 
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