7mm08 QL Please

[Aussie Wanderer]

Hi Guys,

I finally got my 7mm08 barrel threaded onto my rifle and finally got around to shooting it. Seems to go pretty nicely through the tedious run in process.

I have been using Hornady 139sst in Norma brass. Two loads stood out, 42.5 and 44 grains of Varget (AR2208 as we know it here). Barrel length is 24 inches.

I was hoping someone could give me an idea as to pressures. The cartridge base is from the 44 grain load. Looks pretty mild, no hard bolt lift or the like.

Thanks in advance.

AW

 

[jimbires]

looks like max load is 43.0 grains .

Cartridge : 7 mm-08 Rem.
Bullet : .284, 139, Hornady SST InterLock 28202
Useable Case Capaci: 47.897 grain H2O = 3.110 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : ADI AR 2208

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% 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

-20.0 80 34.40 2344 1696 32602 6758 93.1 1.470
-18.0 82 35.26 2397 1774 34683 6949 94.0 1.434
-16.0 84 36.12 2451 1853 36870 7134 94.9 1.400
-14.0 86 36.98 2504 1935 39183 7312 95.7 1.361
-12.0 88 37.84 2557 2017 41636 7483 96.5 1.323
-10.0 90 38.70 2609 2101 44239 7645 97.2 1.287
-08.0 92 39.56 2662 2187 47002 7798 97.8 1.252
-06.0 94 40.42 2714 2273 49934 7943 98.3 1.218
-04.0 96 41.28 2766 2361 53049 8077 98.8 1.186 ! Near Maximum !
-02.0 98 42.14 2818 2450 56358 8201 99.2 1.154 ! Near Maximum !
+00.0 100 43.00 2869 2541 59877 8314 99.5 1.124 !DANGEROUS LOAD-DO NOT USE!
+02.0 102 43.86 2920 2632 63622 8416 99.7 1.095 !DANGEROUS LOAD-DO NOT USE!
+04.0 104 44.72 2971 2724 67609 8506 99.9 1.067 !DANGEROUS LOAD-DO NOT USE!
+06.0 106 45.58 3021 2818 71859 8584 100.0 1.040 !DANGEROUS LOAD-DO NOT USE!
+08.0 108 46.44 3072 2912 76394 8650 100.0 1.014 !DANGEROUS LOAD-DO NOT USE!
+10.0 110 47.30 3121 3007 81237 8711 100.0 0.988 !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 100 43.00 2972 2725 69980 8048 100.0 1.055 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 100 43.00 2724 2291 49967 8250 95.5 1.215



the 44.0 grain load is over pressure by about 4000 PSI


Cartridge : 7 mm-08 Rem.
Bullet : .284, 139, Hornady SST InterLock 28202
Useable Case Capaci: 47.897 grain H2O = 3.110 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : ADI AR 2208

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% 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

-20.0 82 35.20 2394 1768 34535 6936 94.0 1.437
-18.0 84 36.08 2448 1850 36766 7126 94.9 1.402
-16.0 86 36.96 2502 1933 39127 7308 95.7 1.362
-14.0 88 37.84 2557 2017 41636 7483 96.5 1.323
-12.0 90 38.72 2610 2103 44302 7649 97.2 1.286
-10.0 92 39.60 2664 2191 47134 7805 97.8 1.250
-08.0 94 40.48 2718 2279 50145 7952 98.4 1.216
-06.0 97 41.36 2771 2369 53348 8089 98.8 1.183 ! Near Maximum !
-04.0 99 42.24 2824 2461 56756 8215 99.2 1.151 ! Near Maximum !
-02.0 101 43.12 2876 2553 60386 8329 99.5 1.120 !DANGEROUS LOAD-DO NOT USE!
+00.0 103 44.00 2929 2647 64254 8432 99.8 1.091 !DANGEROUS LOAD-DO NOT USE!
+02.0 105 44.88 2980 2742 68379 8522 99.9 1.062 !DANGEROUS LOAD-DO NOT USE!
+04.0 107 45.76 3032 2837 72784 8599 100.0 1.034 !DANGEROUS LOAD-DO NOT USE!
+06.0 109 46.64 3083 2934 77492 8664 100.0 1.008 !DANGEROUS LOAD-DO NOT USE!
+08.0 111 47.52 3134 3031 82529 8726 100.0 0.982 !DANGEROUS LOAD-DO NOT USE!
+10.0 113 48.40 3184 3130 87926 8785 100.0 0.957 !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 103 44.00 3027 2829 75068 8136 100.0 1.025 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 103 44.00 2786 2396 53617 8434 96.4 1.177 ! Near Maximum !



your 42.5 grain load is under pressure by about 2400 PSI

Cartridge : 7 mm-08 Rem.
Bullet : .284, 139, Hornady SST InterLock 28202
Useable Case Capaci: 47.897 grain H2O = 3.110 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : ADI AR 2208

Predicted data by increasing and decreasing the given charge,
incremented in steps of 2.0% 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

-20.0 79 34.00 2319 1660 31669 6667 92.6 1.487
-18.0 81 34.85 2372 1736 33678 6859 93.6 1.451
-16.0 83 35.70 2425 1814 35788 7045 94.5 1.417
-14.0 85 36.55 2477 1894 38009 7224 95.3 1.379
-12.0 87 37.40 2529 1975 40363 7397 96.1 1.342
-10.0 89 38.25 2582 2057 42858 7561 96.8 1.306
-08.0 91 39.10 2634 2141 45504 7718 97.5 1.270
-06.0 93 39.95 2685 2226 48310 7865 98.0 1.237
-04.0 95 40.80 2737 2312 51287 8003 98.5 1.204 ! Near Maximum !
-02.0 97 41.65 2788 2399 54448 8132 99.0 1.172 ! Near Maximum !
+00.0 99 42.50 2839 2488 57805 8250 99.3 1.142 ! Near Maximum !
+02.0 101 43.35 2890 2578 61373 8357 99.6 1.112 !DANGEROUS LOAD-DO NOT USE!
+04.0 103 44.20 2940 2668 65168 8453 99.8 1.084 !DANGEROUS LOAD-DO NOT USE!
+06.0 105 45.05 2990 2760 69208 8538 99.9 1.056 !DANGEROUS LOAD-DO NOT USE!
+08.0 107 45.90 3040 2853 73512 8610 100.0 1.030 !DANGEROUS LOAD-DO NOT USE!
+10.0 109 46.75 3089 2946 78103 8672 100.0 1.005 !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 99 42.50 2944 2674 67569 8003 100.0 1.071 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 99 42.50 2693 2239 48233 8154 95.1 1.235

 

[Aussie Wanderer]

Thank you very much, that is great to know. I liked the shape of 42.5grain load better, that just solidifies my thoughts more so.

 

[jimbires]

here is Hornady info , if you want to see it . I've found their info to be a little conservative.

 

[Aussie Wanderer]

Thank you for the Hornady data, much appreciated. I wondered whether the load data was more max for the copper bullet?

The ADI load data for the Hornady 139 grain projectile had a max load of 43.5 grains of varget running pressures at 50,000cup with the saami spec running 52,000cup.

I just need to get the rifle in the field now. Managed a couple of nice fallow deer last weekend. They will be great on the plate.