STABALL 6.5 7MM-08 154SST QUICK LOAD REQUEST

[Michael C. Smith]

7mm-08 20inch barrel
Staball 6.5 powder
hornady brass 55.3 water capacity
hornady 154sst
coal 2.850
cci-250 primers
temp /humidty 60/68 when this was shot
47.3g gave me 2756 2777 2745 fps
47.6 gave me 2766 2772 2779fps
47.9 gave me 2781 2781 2779 fps
48.2 gave me 2827 2803 2816 fps this was 2 tenths above max. i had hard bolt lift but not awful no ejector marks, the 3 shot group was not good. The other three charges all of those 3 shot groups shot around 3/4 inch @100 all on the same water line except the 48.2 group. I am going to load 47.3 47.6 and 47.9 and shoot again. Can someone please run a quick load for me and see what the psi is showing.

Thank You
Michael Smith

 

[DrMike]

Cartridge          : 7 mm-08 Rem.
Bullet             : .284, 154, Hornady SST InterLock 28302
Useable Case Capaci: 47.461 grain H2O = 3.082 cm³
Cartridge O.A.L. L6: 2.850 inch = 72.39 mm
Barrel Length      : 22.0 inch = 558.8 mm
Powder             : Winchester 6,5 StaBall *T*C

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

-10.0   92    43.38   2332    1859   37430   8205     95.6    1.369
-09.0   93    43.86   2359    1902   38692   8303     96.1    1.347
-08.0   94    44.34   2386    1946   40000   8397     96.5    1.327
-07.0   95    44.83   2413    1990   41358   8488     97.0    1.306
-06.0   96    45.31   2440    2035   42768   8576     97.4    1.286
-05.0   97    45.79   2467    2081   44231   8660     97.7    1.266
-04.0   98    46.27   2494    2127   45749   8741     98.1    1.246
-03.0   99    46.75   2521    2173   47327   8817     98.4    1.227
-02.0  100    47.24   2548    2220   48967   8890     98.7    1.208
-01.0  101    47.72   2575    2268   50672   8958     98.9    1.190
+00.0  102    48.20   2602    2316   52444   9023     99.2    1.172  ! Near Maximum !
+01.0  103    48.68   2630    2364   54291   9083     99.4    1.154  ! Near Maximum !
+02.0  104    49.16   2657    2414   56213   9138     99.5    1.136  ! Near Maximum !
+03.0  105    49.65   2684    2463   58214   9189     99.7    1.119  ! Near Maximum !
+04.0  106    50.13   2711    2513   60297   9235     99.8    1.102  !DANGEROUS LOAD-DO NOT USE!
+05.0  107    50.61   2738    2563   62472   9277     99.9    1.085  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 5% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 5% relative to nominal value:
+Ba    102    48.20   2668    2435   57473   8911    100.0    1.127  ! Near Maximum !
Data for burning rate decreased by 5% relative to nominal value:
-Ba    102    48.20   2525    2179   47691   8990     97.0    1.223

You have room by this projection before you push excessive pressure.

Cartridge          : 7 mm-08 Rem.
Bullet             : .284, 154, Hornady SST InterLock 28302
Useable Case Capaci: 47.461 grain H2O = 3.082 cm³
Cartridge O.A.L. L6: 2.850 inch = 72.39 mm
Barrel Length      : 22.0 inch = 558.8 mm
Powder             : Winchester 6,5 StaBall *T*C

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

-10.0   95    44.91   2417    1998   41601   8504     97.0    1.302
-09.0   96    45.41   2445    2045   43070   8594     97.4    1.282
-08.0   97    45.91   2473    2092   44597   8680     97.8    1.261
-07.0   99    46.41   2502    2140   46185   8762     98.2    1.241
-06.0  100    46.91   2530    2188   47837   8841     98.5    1.221
-05.0  101    47.41   2558    2237   49557   8914     98.8    1.202
-04.0  102    47.90   2586    2286   51348   8984     99.0    1.183  ! Near Maximum !
-03.0  103    48.40   2614    2336   53214   9048     99.2    1.164  ! Near Maximum !
-02.0  104    48.90   2642    2387   55158   9109     99.4    1.146  ! Near Maximum !
-01.0  105    49.40   2670    2438   57185   9164     99.6    1.128  ! Near Maximum !
+00.0  106    49.90   2698    2489   59300   9214     99.8    1.110  ! Near Maximum !
+01.0  107    50.40   2726    2541   61509   9259     99.9    1.092  !DANGEROUS LOAD-DO NOT USE!
+02.0  108    50.90   2754    2594   63815   9299     99.9    1.075  !DANGEROUS LOAD-DO NOT USE!
+03.0  109    51.40   2782    2647   66224   9333    100.0    1.058  !DANGEROUS LOAD-DO NOT USE!
+04.0  110    51.90   2810    2700   68745   9362    100.0    1.041  !DANGEROUS LOAD-DO NOT USE!
+05.0  111    52.40   2838    2754   71381   9388    100.0    1.025  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 5% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 5% relative to nominal value:
+Ba    106    49.90   2760    2606   65054   9029    100.0    1.068  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 5% relative to nominal value:
-Ba    106    49.90   2623    2352   53859   9264     98.3    1.157  ! Near Maximum !

 

[Michael C. Smith]

Thanks Dr. Mike. something seems off with the data from Quick load. it is way off from what was measured fps from the garmin.I got these velocitys with 47.9 It gave me 2781 2781 2779 fps. QL is showing 47.9 2586 with a 22inch barrel i have a 20. Hodgen is showing 48.1 for the max load 48.1 2871fps. I wonder whats up?

 

[RL338]

Your data is more in line with Hornady’s.

 

[Michael C. Smith]

Your data is more in line with Hornady’s.
View attachment 25361

Your data is more in line with Hornady’s.
View attachment 25361

Mine came off og the hodgen site. I wonder why quick load is so far off?

 

[DrMike]

I've rechecked all the input data and really have no answer. I would trust the tested data from Hodgdon and Hornady. I did note that I calculated for a 22 inch barrel, which would actually yield a somewhat higher velocity. I questioned the lower MAP given for the 7mm-08, but it is right in line with the SAAMI standard. I really don't have an answer. What is apparent is that you are not exceeding maximum pressure. This is the reason we are dependent upon our own testing given our firing system.

 

[jimbires]

I ran the info in my quickload too . I came up with the same info as Dr Mike . my quickload is a few years old, I wanted to see if there might be a glitch in the newer version of quickload , I know Dr Mike keeps his pretty well up to date .


the only thing I recommend is double check your scale with some check weights , to be sure nothing happened to it .

 

[Michael C. Smith]

Thanks guys. I will load up 47.3 47.6 47.9 again and shoot them for groups and see if the repeat with fps and group size. I checked my charge master with my rcbs beam scale everything was good there. The two lower charges shot moa at 100y the 47.9 load shot 0.78 at 100y. This is the 47.9 group.

 

[JD338]

Nothing wrong with that load.
Let us know how the reshoot goes.

JD338

 

[wvbuckbuster]

Looks good to me. I like Stabal 6.5 Does pretty good in my 7mm08. Good for other calibers also. Dan.

 

[RiverRider]

Try as you might, you're never going to get real precision out of QuicklOAD.

Many have believed they figured it out, pointing out their success at adjusting the Ba so that the velocity results with a certain combination of components closely tracks with QL predictions. BTDT myself...and I found out quickly that this Ba figure I'd come up with did not come close to syncing velocity predictions with that same powder in another cartridge.

Why? Because you have too many variables that figure into the calculations and which affect the outcome. Case volume measured with water is fairly simple to figure out, but then you're till faced with variations within a lot of brass. But there's more: the Weighting Factor, which is set at 50 by default, will cause significant changes when the value is tweaked and the problem is that if you do not have an absolutely, reliably correct Ba then you can't nail down a precise Weighting Factor.

But wait, there's more! Start Pressure will also figure significantly in the velocity predictions, and we have no way at all to determine what the value plugged into that field should be. By default it is 3626 PSI, but I am pretty sure you'll never be able to nail that particular value down either.

In the end analysis we have 3 values we cannot solve for because they all interact with the end result. QL is a great tool if used properly, and in my mind its best and highest use is to provide a usable pressure estimate based on measured velocities. It's also a great way to learn some of the subtleties of internal ballistics, and if used with great caution and a smidgen of common sense it can help keep you from inadvertently disassembling a rifle while experimenting...but NEVER should it be used independent of whatever published loading data can be found.

 

[DrMike]

Try as you might, you're never going to get real precision out of QuicklOAD.

Many have believed they figured it out, pointing out their success at adjusting the Ba so that the velocity results with a certain combination of components closely tracks with QL predictions. BTDT myself...and I found out quickly that this Ba figure I'd come up with did not come close to syncing velocity predictions with that same powder in another cartridge.

Why? Because you have too many variables that figure into the calculations and which affect the outcome. Case volume measured with water is fairly simple to figure out, but then you're till faced with variations within a lot of brass. But there's more: the Weighting Factor, which is set at 50 by default, will cause significant changes when the value is tweaked and the problem is that if you do not have an absolutely, reliably correct Ba then you can't nail down a precise Weighting Factor.

But wait, there's more! Start Pressure will also figure significantly in the velocity predictions, and we have no way at all to determine what the value plugged into that field should be. By default it is 3626 PSI, but I am pretty sure you'll never be able to nail that particular value down either.

In the end analysis we have 3 values we cannot solve for because they all interact with the end result. QL is a great tool if used properly, and in my mind its best and highest use is to provide a usable pressure estimate based on measured velocities. It's also a great way to learn some of the subtleties of internal ballistics, and if used with great caution and a smidgen of common sense it can help keep you from inadvertently disassembling a rifle while experimenting...but NEVER should it be used independent of whatever published loading data can be found.

Bingo! This is why you are responsible for your own firing system. You are responsible for verifying pressure signs, minimum charges, maximum charges, etc.