Staball 6.5 .308 and 7mm-08

[PRSDietitian]

I've been curious of this. So I have a good bit of Staball 6.5 on hand because my 6GT loves it. I decided to repurpose a tikka CTR for Tac division and looked at .308 load data for Staball. Hodgdon has it for 7mm-08 but not .308 win, it does have the Staball match though. 6.5 seems to do great on the 7mm, "supposedly" giving 2800+ the 162gr bullets. With that being said, why would it perform well in the same case just necked down, but not the parent case?

 

[RogueTanker]

With the standard 7/08 you can get 2800 with XBR. With the Ackley, you can easily get 2850 with XBR or varget. With staball in the Ackley with 162s, I got to 2916 with 50.4 grains in a 25" barrel.

 

[PRSDietitian]

With the standard 7/08 you can get 2800 with XBR. With the Ackley, you can easily get 2850 with XBR or varget. With staball in the Ackley with 162s, I got to 2916 with 50.4 grains in a 25" barrel.

Any experience with 6.5 in the 308

 

[918v]

It’s too slow burning in the 308. Use the right powder for the caliber.

 

[PRSDietitian]

My question is, why is it suitable for other cartridges using the .308 parent case, but not the .308?

 

[RogueTanker]

My question is, why is it suitable for other cartridges using the .308 parent case, but not the .308?

Not being a more read up person, I'd hazard a guess that the larger bore diameter allows pressure to build differently and to get the best pressure and speed you'll need a different burn rate compared to a smaller diameter bullet of the 7mm and smaller cartridges.

 

[PRSDietitian]

After i posted that i did come across this on accurate shooter

"
The case capacity to bore ratio is one of the two key metrics in internal ballistics affecting powder burn rate. (The other is bullet weight.) The usual method of determining the first is to divide case capacity as measured by the weight of water it holds in grains by the bore area in square inches. The lower the value of the result, the faster burning the powder; the reverse for higher numbers.

Using 56gn water capacity for all 308 Win variants (to reduce effort - they vary by a grain or two in practice according to calibre) you get:

243 Win ...... (0.046) ......... 1,196

260 Rem ...... (0.055) ........ 1,000

7mm-08 ...... (0.063) ......... 873

308 Win ...... (0.075) ......... 747

338 Fed ...... (0.090) ......... 622

358 Win ..... (0.100) ........ 560

The figures in brackets are the bore areas in square inches.

7mm-08 and 308 with ratios of ~ 873 and 747 respectively are far enough apart to justify different burn rate powders for optimal performance, although the 7mm-08's value is still low enough to still see good results with fast to mid-speed propellants like VarGet. (Its ratio is very close to 6.5X47mm Lapua's, another design that straddles the VarGet / 4350 powder watershed.)

At 747, 308 Win is a step lower, and counter-intuitively, is very close to that of 223 Rem - why they both find the same range of powders optimal usually.

The other factors are custom extended throats (which have the same effect as increasing case capacity through seating any given bullet less deeply in the case), and bullet weight. Because of the different bore sizes, 175gn 284 and 308 bullets aren't directly comparable. On a 'scaled' basis, a 175gn 7mm bullet is roughly equivalent to a 200gn 30-cal design.

I shoot a long-throat 7mm-08 in F-Class with the 160gn Sierra TMK normally. My usual powders are Lovex SO65 (Shooters World Long Rifle in the US) and Viht N160. Neither is a suitable powder for 308 Win. Powders suitable in 308 work in this set-up, but usually pressure-out at around 100 fps lower than the slower burners. Despite a throat long enough to see bullets loaded to just short of 3-inch COALs, I've tried and rejected 175s in the cartridge as requiring over-compressed charges and producing insufficient velocities. (You can use them in the cartridge, but they need still more freebore than my chamber has.)"

I'm trying to get the 176 a tip to around 2700-2750 fps so im looking at powder selection now. I have staball match on hand but i dpn't think it'll quite get me there. Might hunt for some 8208-xbr for that

 

[Schütze]

It’s too slow burning in the 308. Use the right powder for the caliber.

This suggests otherwise?

Staball Match range report (308)

Tested Staball match in 308 with 178 ELD-M. Tested 44.2 up to Hodgdon max 46gr. After 44.2gr it really tightened up. Very happy with the accuracy. First ever test with this powder so only did 4-shot groups. Next time I will bring the chrono and verify 46.0 range and report back with velocities.

www.snipershide.com

 

[PRSDietitian]

This suggests otherwise?

Staball Match range report (308)

Tested Staball match in 308 with 178 ELD-M. Tested 44.2 up to Hodgdon max 46gr. After 44.2gr it really tightened up. Very happy with the accuracy. First ever test with this powder so only did 4-shot groups. Next time I will bring the chrono and verify 46.0 range and report back with velocities.

www.snipershide.com

Is that for staball 6.5 as well or just Staball Match?

 

[Schütze]

Is that for staball 6.5 as well or just Staball Match?

My apologies, missed that part….

But it wouldn’t surprise me if Staball 6.5 could be used for.308

Do some research, I’m sure testing ha been done by someone?

 

[Schütze]

@ddavis I have to eat my words. I would also classify StaBall as too slow for 308. Best I could get was just over 2900. But that isn't great for a 29" barrel shooting 155 Palma MKs. I was doing 3050 with Varget. The ES was all over the place at 50grs because it was compressed. I would say 49grs is a more realistic top end at just a light compression. That was doing 2830. So about 200fps too slow.

Edit: this is with a 29", 1:13" 308 using Lapua LRP, 155SMK Palma at 2.810" COAL.

Looks like 918v is correct regarding Staball 6.5. Have to get use to 3 different Staball versions….

 

[PRSDietitian]

wish they'd just make more varget, H4350 and Retumbo

 

[Cr1775]

Sorry Winchester doesn't make Varget, H4350 or Retumbo.

 

[PRSDietitian]

true, they're just distributed and licensed but still...

 

[Cr1775]

Yes just like Hodgdon, but now i do see Varget more often than not on the shelves at the stores, and most primers, but anybody been seeing large rifle or large rifle magnum yet?

 

[PRSDietitian]

Seen some CCI 450 and 400 at around 110 per 1000...

 

[turbo406]

Just bought a brick of large rifle cci at 90 bucks a brick buck that seems to be the new price around here, no magnum yet unfortunately so going to have to be doing some testing with standard large rifle primers on my 300 win for hunting season.

 

[fdkay]

With the standard 7/08 you can get 2800 with XBR. With the Ackley, you can easily get 2850 with XBR or varget. With staball in the Ackley with 162s, I got to 2916 with 50.4 grains in a 25" barrel.

Sounds exciting. I'm going to build a hunting rifle, my smith has a good AI reamer. What cases were you using?
My straight 7-08, I'm necking down starline srp .308 brass.
I'll likely use LRP brass for the AI

 

[RogueTanker]

Sounds exciting. I'm going to build a hunting rifle, my smith has a good AI reamer. What cases were you using?
My straight 7-08, I'm necking down starline srp .308 brass.
I'll likely use LRP brass for the AI

I've been using either PPU or LC LR 11 Brass.

 

[Rockhurr]

Sorry Winchester doesn't make Varget, H4350 or Retumbo.

Staball 6.5 is made by Hodgdon isn’t it, thou it says Winchester on the bottle.

 

[Cr1775]

Staball 6.5 is made by Hodgdon isn’t it, thou it says Winchester on the bottle.

Hodgdon doesn't make any powder they have it made for them.

 

[Preston Cropley]

Staball 6.5 is made by Hodgdon isn’t it, thou it says Winchester on the bottle.

No, Winchester StaBall powder is made by St. Marks Powder.

 

[357Max]

Staball 6.5 is way to slow for 308.

I'm also putting together a TAC class 308. Patiently waiting on the CDG action & PVA barrel.

Impatience got the better of me so I decided to play with some 308 loads in the 18" AR.

Just shot my first ladders of Staball Match in 308 with 168smk & 176 A-tip.
It's showing promise with 168smk's
FGMM 168 x 5 across the magneto V3 as control = 2516
Staball match 168smk @ 2.800 with 46.4 x 5 = 2612 Group was .692" @ 100
Black Hills Brass & CCi #34

They don't list the A-tip in the load data for the match, so I used 175smk data. Don't do that!
46.0 is max for 175smk @2.800
I loaded up to 45.6 with the 176 A-tip @ 2.875 This was way to hot & lost 2 of 5 primers. This was also in a 18" AR

Start well below 45.0 for Staball Match with the 176 a-tips & that's if your loading long 2.875+
I'd bet 44.6 of Match will get you 2700 in a bolt gun with the 176 A-tips.

I also played with a few ladders using Lever. I'm ashamed to print speeds for those from this AR. Let's just say Lever is not to slow for 308, not at all.
If your feeling froggy start @ 44.8 Lever with the 176's loaded 2.875+

 

[FuhQ]

Just finished some load development in my 20" Christensen Ridgeline FFT 7mm-08 and StaBall 6.5 with the Berger 175 Elite Hunters... My best safe load was 46.0 grains and was pushing them 2,614 FPS MV average with a single-digit SD. Pretty happy with it. If it stays stable during the cold weather, I will be using it for hunting season for deer.

Here’s the same group both with, and without, the flier that I pulled…

 

[45-90]

Staball 6.5 is a good powder for 308 with 208 gr to 230gr bullets.
I'm running 230 gr Atips at 2620 fps in a 8 twist 30" barrel, Long Action, chassis stocked 308.