Elwood Posted January 22, 2010 Report Share Posted January 22, 2010 Due to upgrading to windows 7 my QL doesn't work, hopefully a new updated QL will be with me soon. Could some kind soul please run a few figures for me? I'm looking for minimum and maximum case capacity. 6BR barrel length 23 VV N133 Hornady 75 grain V max COL 2.202 Link to comment Share on other sites More sharing options...
6mmBR Posted January 22, 2010 Report Share Posted January 22, 2010 Here you go Ian Cartridge : 6 mm B.R. Norma Bullet : .243, 75, Hornady V-MAX 22420 Useable Case Capaci: 34.797 grain H2O = 2.259 cm³ Cartridge O.A.L. L6: 2.202 inch = 55.93 mm Barrel Length : 23.0 inch = 584.2 mm Powder : Vihtavuori N133 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 24.00 2575 1104 30249 6163 96.3 1.305 -18.0 84 24.60 2631 1153 32195 6312 97.1 1.275 -16.0 86 25.20 2687 1203 34246 6453 97.8 1.245 -14.0 88 25.80 2743 1253 36399 6584 98.4 1.216 -12.0 90 26.40 2798 1304 38673 6706 98.9 1.185 -10.0 92 27.00 2853 1355 41083 6818 99.3 1.153 -08.0 94 27.60 2907 1407 43637 6920 99.6 1.122 -06.0 96 28.20 2961 1460 46344 7011 99.8 1.093 -04.0 98 28.80 3014 1513 49215 7091 99.9 1.064 -02.0 100 29.40 3066 1566 52260 7159 100.0 1.037 ! Near Maximum ! +00.0 102 30.00 3118 1619 55491 7220 100.0 1.011 ! Near Maximum ! +02.0 104 30.60 3170 1673 58922 7279 100.0 0.985 !DANGEROUS LOAD-DO NOT USE! +04.0 106 31.20 3220 1727 62566 7336 100.0 0.961 !DANGEROUS LOAD-DO NOT USE! +06.0 108 31.80 3271 1781 66440 7391 100.0 0.937 !DANGEROUS LOAD-DO NOT USE! +08.0 110 32.40 3320 1836 70562 7444 100.0 0.914 !DANGEROUS LOAD-DO NOT USE! +10.0 112 33.00 3370 1891 74950 7495 100.0 0.892 !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 102 30.00 3213 1719 65168 6954 100.0 0.949 !DANGEROUS LOAD-DO NOT USE! Data for burning rate decreased by 10% relative to nominal value: -Ba 102 30.00 2975 1474 45918 7402 98.2 1.093 Cheers Dave Link to comment Share on other sites More sharing options...
Elwood Posted January 22, 2010 Author Report Share Posted January 22, 2010 Thanks Dave, you're a star. Link to comment Share on other sites More sharing options...
6mmBR Posted January 22, 2010 Report Share Posted January 22, 2010 Looking at those figures Ian, I recon you'll get better velocities with N135. Cartridge : 6 mm B.R. Norma Bullet : .243, 75, Hornady V-MAX 22420 Useable Case Capaci: 34.797 grain H2O = 2.259 cm³ Cartridge O.A.L. L6: 2.202 inch = 55.93 mm Barrel Length : 23.0 inch = 584.2 mm Powder : Vihtavuori N135 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 88 25.60 2579 1108 28019 6613 94.9 1.350 -18.0 90 26.24 2641 1162 29961 6786 95.9 1.314 -16.0 92 26.88 2703 1216 32036 6948 96.8 1.279 -14.0 95 27.52 2764 1272 34263 7099 97.6 1.246 -12.0 97 28.16 2825 1329 36653 7238 98.2 1.213 -10.0 99 28.80 2885 1387 39214 7363 98.8 1.176 -08.0 101 29.44 2946 1445 41930 7476 99.3 1.142 -06.0 103 30.08 3005 1504 44821 7574 99.6 1.109 -04.0 106 30.72 3065 1564 47916 7657 99.9 1.077 -02.0 108 31.36 3123 1624 51229 7725 100.0 1.046 ! Near Maximum ! +00.0 110 32.00 3181 1685 54779 7778 100.0 1.016 ! Near Maximum ! +02.0 112 32.64 3238 1747 58586 7825 100.0 0.987 !DANGEROUS LOAD-DO NOT USE! +04.0 114 33.28 3295 1808 62671 7871 100.0 0.960 !DANGEROUS LOAD-DO NOT USE! +06.0 117 33.92 3351 1870 67061 7914 100.0 0.933 !DANGEROUS LOAD-DO NOT USE! +08.0 119 34.56 3407 1933 71784 7954 100.0 0.907 !DANGEROUS LOAD-DO NOT USE! +10.0 121 35.20 3462 1996 76870 7991 100.0 0.883 !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 110 32.00 3298 1811 66440 7433 100.0 0.943 !DANGEROUS LOAD-DO NOT USE! Data for burning rate decreased by 10% relative to nominal value: -Ba 110 32.00 3004 1502 43492 7965 97.5 1.115 Link to comment Share on other sites More sharing options...
Elwood Posted January 22, 2010 Author Report Share Posted January 22, 2010 Hi Dave, N135 was my first port of call, accuracy was ok but not BR standards. I have also tried RL15 which faired better, half inch 3 shot groups and while ok still not acceptable for a 6BR. I suspect I'm pissing in the wind trying to get 75 grain bullets to shoot from a 1-8 barrel. Common sense tells me to try 87 gr V Max or 88 gr Berger's, but I don't have any and I'm not sure when I will able to get hold of them. Link to comment Share on other sites More sharing options...
6mmBR Posted January 22, 2010 Report Share Posted January 22, 2010 I can bring some down for you to try next weekend. Cheers Dave Link to comment Share on other sites More sharing options...
varmartin Posted January 23, 2010 Report Share Posted January 23, 2010 Edited... Double post. Link to comment Share on other sites More sharing options...
varmartin Posted January 23, 2010 Report Share Posted January 23, 2010 33.5 gns R15 works very well for me giving 3250fps from my 1-8 krieger 6MMBR Norma throated for 105 Amax, note.... this is a case filling slightly compressed load... Summer or winter no problems . Link to comment Share on other sites More sharing options...
Elwood Posted January 23, 2010 Author Report Share Posted January 23, 2010 33.5 gns R15 works very well for me giving 3250fps frommy 1-8 krieger 6MMBR Norma throated for 105 Amax, note.... this is a case filling slightly compressed load... Summer or winter no problems . Martin, my barrel is also throated for the 105 Amax, how far are you jumping the the 75's ? Link to comment Share on other sites More sharing options...
varmartin Posted January 23, 2010 Report Share Posted January 23, 2010 When Russell built my rifle he also supplied me with a barrel stub that was `short chambered` Using that as a guide my loaded rounds with 75 Vmax are 0.006 off the lands, but with a small amount of throat ware after 1500 rounds say a few thou at worst last measurement was +0.004.( most of that was shooting the throat in ) So lets say 0.010 off the lands. I expect some of you will be surprised that a chamber cut for 105`s can still seat a 75grn bullet close to the lands... For reference ....33.5 grains of R15 in the case, a 75 Vmax sits right on top of the powder charge....with just a slight `crunch`and the base of the bullet is right on the shoulder /neck junction... edited to add. COL. for the 75Vmax is ..1.765 to the ogive using a stoney point tool. Link to comment Share on other sites More sharing options...
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