7mm Mag Vihtavuori 160gr Partition load data needed.

[kickerz24]

I need to load up a friends 7MM Mag Ruger MKII for an elk hunt this fall. I have a lot of Vihtavuori powder on hand and have some Nosler Partition 160gr on hand. Has anyone had any luck with this bullet and any of the VV powders listed below? The only Nosler data listed is with N165, which I do not currently have any on hand.
N170
N550
N560
N570
Thanks

 

[DrMike]

http://www.vihtavuori.com/en/reloading-data/rifle-reloading/7-mm-remington-magnum.html

A good starting place. Unfortunately, my QL is down at the moment.

 

[kickerz24]

I saw that but they done have this bullet listed, can I just use any bullet they have listed under 160gr and start 10% below their max charge and work up?

 

[DrMike]

Your suggestion is reasonable. I have often taken information provided such as that from VihtaVuori, dropped back 10% and worked up in one grain increments, watching for signs of pressure. It is not optimal, but it is quite safe so long as you recognize signs of excessive pressure and drop back when they are encountered. Others with QL loaded will be along soon if you prefer to wait.

 

[DrMike]

Working off an old program and reviewing old notes, I see a maximum of N550 with 160 g PT of 61.0 grains., 68 grains of N560, 74 grains of N170 and 76.9 grains of N570. I use a lot of VihtaVuori powders in my own work, but N165 was my "go to" powder in the 7RM. Hope that helps.

Again, I am I the middle of a computer rebuild at the moment or I would give a projection.

 

[jimbires]

I used a 24 inch bbl

Cartridge : 7 mm Rem. Mag.(SAAMI)
Bullet : .284, 160, Nosler PART SP 16327
Useable Case Capaci: 74.317 grain H2O = 4.825 cm³
Cartridge O.A.L. L6: 3.290 inch = 83.57 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Vihtavuori N170

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 87 59.20 2300 1879 29981 9944 81.8 1.668
-18.0 90 60.68 2363 1983 32101 10319 83.4 1.623
-16.0 92 62.16 2426 2091 34379 10691 84.9 1.579
-14.0 94 63.64 2490 2203 36826 11056 86.4 1.536
-12.0 96 65.12 2555 2319 39457 11414 87.8 1.485
-10.0 98 66.60 2620 2439 42287 11763 89.1 1.436
-08.0 100 68.08 2686 2563 45333 12102 90.4 1.388
-06.0 103 69.56 2752 2690 48613 12429 91.7 1.342
-04.0 105 71.04 2818 2822 52149 12742 92.8 1.298 ! Near Maximum !
-02.0 107 72.52 2885 2957 55966 13040 93.9 1.255 ! Near Maximum !
+00.0 109 74.00 2952 3096 60092 13322 94.9 1.214 ! Near Maximum !
+02.0 111 75.48 3020 3240 64556 13584 95.8 1.174 !DANGEROUS LOAD-DO NOT USE!
+04.0 114 76.96 3088 3387 69397 13827 96.7 1.135 !DANGEROUS LOAD-DO NOT USE!
+06.0 116 78.44 3156 3538 74653 14048 97.4 1.098 !DANGEROUS LOAD-DO NOT USE!
+08.0 118 79.92 3224 3693 80374 14245 98.1 1.062 !DANGEROUS LOAD-DO NOT USE!
+10.0 120 81.40 3293 3852 86614 14416 98.7 1.027 !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 109 74.00 3118 3454 72292 13500 99.2 1.116 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 109 74.00 2742 2671 48376 12517 86.9 1.340


Cartridge : 7 mm Rem. Mag.(SAAMI)
Bullet : .284, 160, Nosler PART SP 16327
Useable Case Capaci: 74.317 grain H2O = 4.825 cm³
Cartridge O.A.L. L6: 3.290 inch = 83.57 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Vihtavuori N550

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 70 49.04 2439 2114 34033 10255 97.9 1.579
-18.0 72 50.27 2493 2208 36130 10499 98.5 1.544
-16.0 74 51.49 2547 2304 38339 10729 99.0 1.504
-14.0 75 52.72 2600 2402 40665 10943 99.4 1.460
-12.0 77 53.94 2653 2500 43114 11141 99.7 1.420
-10.0 79 55.17 2705 2599 45692 11321 99.9 1.380
-08.0 81 56.40 2756 2699 48406 11483 100.0 1.343
-06.0 82 57.62 2807 2800 51263 11630 100.0 1.307
-04.0 84 58.85 2857 2901 54271 11773 100.0 1.272 ! Near Maximum !
-02.0 86 60.07 2907 3003 57438 11913 100.0 1.239 ! Near Maximum !
+00.0 88 61.30 2956 3105 60774 12051 100.0 1.207 !DANGEROUS LOAD-DO NOT USE!
+02.0 89 62.53 3005 3208 64287 12187 100.0 1.176 !DANGEROUS LOAD-DO NOT USE!
+04.0 91 63.75 3053 3312 67990 12319 100.0 1.146 !DANGEROUS LOAD-DO NOT USE!
+06.0 93 64.98 3101 3417 71893 12450 100.0 1.117 !DANGEROUS LOAD-DO NOT USE!
+08.0 95 66.20 3149 3522 76010 12577 100.0 1.090 !DANGEROUS LOAD-DO NOT USE!
+10.0 96 67.43 3196 3628 80354 12701 100.0 1.063 !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 88 61.30 3045 3295 70950 11717 100.0 1.127 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 88 61.30 2822 2830 50469 12417 99.3 1.313


Cartridge : 7 mm Rem. Mag.(SAAMI)
Bullet : .284, 160, Nosler PART SP 16327
Useable Case Capaci: 74.317 grain H2O = 4.825 cm³
Cartridge O.A.L. L6: 3.290 inch = 83.57 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Vihtavuori N560

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 78 54.40 2422 2084 31178 11059 89.1 1.609
-18.0 80 55.76 2484 2192 33290 11435 90.5 1.567
-16.0 82 57.12 2546 2304 35537 11800 91.8 1.527
-14.0 84 58.48 2609 2418 37956 12152 93.0 1.485
-12.0 85 59.84 2672 2536 40534 12492 94.2 1.439
-10.0 87 61.20 2734 2656 43289 12815 95.2 1.394
-08.0 89 62.56 2797 2779 46235 13122 96.1 1.352
-06.0 91 63.92 2859 2905 49359 13410 97.0 1.311
-04.0 93 65.28 2922 3033 52671 13678 97.7 1.271 ! Near Maximum !
-02.0 95 66.64 2984 3163 56203 13924 98.4 1.233 ! Near Maximum !
+00.0 97 68.00 3046 3296 59971 14148 98.9 1.197 ! Near Maximum !
+02.0 99 69.36 3108 3431 63993 14348 99.3 1.162 !DANGEROUS LOAD-DO NOT USE!
+04.0 101 70.72 3169 3568 68289 14523 99.7 1.128 !DANGEROUS LOAD-DO NOT USE!
+06.0 103 72.08 3230 3707 72881 14671 99.9 1.095 !DANGEROUS LOAD-DO NOT USE!
+08.0 105 73.44 3291 3848 77795 14792 100.0 1.063 !DANGEROUS LOAD-DO NOT USE!
+10.0 107 74.80 3351 3990 83059 14887 100.0 1.032 !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 97 68.00 3191 3617 72286 13760 100.0 1.104 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 97 68.00 2846 2877 48063 13751 93.1 1.319


Cartridge : 7 mm Rem. Mag.(SAAMI)
Bullet : .284, 160, Nosler PART SP 16327
Useable Case Capaci: 74.317 grain H2O = 4.825 cm³
Cartridge O.A.L. L6: 3.290 inch = 83.57 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Vihtavuori N570

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 85 61.44 2373 2000 28650 11486 81.1 1.661
-18.0 87 62.98 2443 2120 30760 11974 83.0 1.615
-16.0 89 64.51 2514 2246 33040 12453 84.9 1.570
-14.0 91 66.05 2587 2377 35509 12922 86.7 1.527
-12.0 94 67.58 2660 2513 38183 13378 88.4 1.478
-10.0 96 69.12 2734 2655 41084 13817 90.0 1.426
-08.0 98 70.66 2808 2802 44235 14237 91.5 1.376
-06.0 100 72.19 2883 2954 47662 14634 92.9 1.328
-04.0 102 73.73 2959 3111 51393 15006 94.2 1.281
-02.0 104 75.26 3035 3273 55464 15351 95.4 1.236 ! Near Maximum !
+00.0 106 76.80 3112 3440 59912 15665 96.5 1.193 ! Near Maximum !
+02.0 108 78.34 3189 3612 64782 15945 97.4 1.151 !DANGEROUS LOAD-DO NOT USE!
+04.0 111 79.87 3266 3789 70124 16189 98.2 1.110 !DANGEROUS LOAD-DO NOT USE!
+06.0 113 81.41 3343 3970 75983 16394 98.8 1.070 !DANGEROUS LOAD-DO NOT USE!
+08.0 115 82.94 3420 4155 82385 16557 99.4 1.032 !DANGEROUS LOAD-DO NOT USE!
+10.0 117 84.48 3497 4345 89415 16676 99.7 0.995 !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 106 76.80 3312 3896 75512 15566 99.9 1.083 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 106 76.80 2848 2882 46745 14658 87.4 1.333

 

[super-7]

I have the last VIHTAVORI manual and the quick load from above falls in line with the loads they give.
They have 2 - 160 gr loads one being a Speer grand slam the other a Sierra pro hunter.

 

[super-7]

 

[SJB358]

Looks like N560 is pretty danged good looking at speed and PSI's produced. Good luck. Have heard nothing but excellent things about the powder.

 

[kickerz24]

Thank you for the quick replies. When I am looking at this data what is the best way to choose a powder? I see the N570 has the fastest velocity and Energy but at a compressed load. Should I be looking for a powder that will fill the case just under 100% such as the N560 @ 97%?.

Thanks

 

[DrMike]

There are a variety of factors in choosing a powder. Availability is a major concern in recent years. I do look for a case fill of 95% to 110% if velocity is decent and if the particular powder is available. I've used each of the particular powders you named; I really like VihtaVuori powders. I would be inclined to look at the double base powders in this instance (N560 and N570 in particular).

 

[sbsmith]

After experimenting with several different powders (R-19, R-22, 7828, both 4831's, 4350's, H1000, Magnum etc) I settled on N560 w/160 AccuBond for my Tikka 7 Mag. In the first Vihtavouri manual, loads are listed for 560 that may give some a reason for pause. That said, in my rifle, 560 gives the best results. Very fast and very accurate, no pressure signs even though Quickload may disagree.
just my .02.
sbsmith

 

[DrMike]

Spammer. I console myself with the knowledge that the brightest light draws the most moths. Guess this critter recognises where the quality people hang out.