QL 260 Rem 120 NBT H4350

MAinAR · Aug 15, 2016

Would someone help me out with QL on 260 Rem 24" barrel & H4350. OAL I am starting with is 2.77 with 120 NBT.

MAinAR · Aug 15, 2016

Looking for approx velocity for OBT 1.1 or 1.22

MAinAR · Aug 15, 2016

This may help.... 2.75 OAL

Magnetospeed readings
2822
2819
2818

43 gr H4350

TackDriver284 · Aug 15, 2016

Cartridge : .260 Rem
Bullet : .264, 120, Nosler BalTip 26120
Useable Case Capaci: 47.027 grain H2O = 3.053 cm³
Cartridge O.A.L. L6: 2.770 inch = 70.36 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Hodgdon H4350

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 !

Code:

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

-10.0   93    39.60   2630    1843   41573   8523     93.0    1.329
-09.0   94    40.04   2658    1883   42912   8628     93.5    1.310
-08.0   95    40.48   2687    1924   44299   8731     94.0    1.291
-07.0   97    40.92   2715    1965   45731   8832     94.4    1.272
-06.0   98    41.36   2744    2006   47208   8930     94.9    1.254
-05.0   99    41.80   2773    2048   48727   9026     95.3    1.236
-04.0  100    42.24   2801    2091   50291   9119     95.7    1.218
-03.0  101    42.68   2830    2134   51902   9209     96.1    1.201  ! Near Maximum !
-02.0  102    43.12   2858    2177   53567   9297     96.5    1.184  ! Near Maximum !
-01.0  103    43.56   2887    2221   55288   9382     96.8    1.167  ! Near Maximum !
+00.0  104    44.00   2915    2265   57066   9464     97.1    1.151  ! Near Maximum !
+01.0  105    44.44   2944    2309   58906   9543     97.5    1.135  ! Near Maximum !
+02.0  106    44.88   2972    2354   60807   9619     97.8    1.119  !DANGEROUS LOAD-DO NOT USE!
+03.0  107    45.32   3001    2399   62775   9692     98.0    1.104  !DANGEROUS LOAD-DO NOT USE!
+04.0  108    45.76   3029    2445   64810   9762     98.3    1.088  !DANGEROUS LOAD-DO NOT USE!
+05.0  109    46.20   3058    2491   66917   9828     98.6    1.073  !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    104    44.00   3049    2476   67424   9396     99.9    1.072  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    104    44.00   2741    2002   46988   9101     90.8    1.253

MAinAR · Aug 15, 2016

Thank you!!!!

MAinAR · Aug 15, 2016

What does OBT do if you adjust speed to 2820 at 43 gr H4350 and OAL at 2.75" in 24" barrel???

TackDriver284 · Aug 15, 2016

Cartridge : .260 Rem
Bullet : .264, 120, Nosler BalTip 26120
Useable Case Capaci: 47.442 grain H2O = 3.080 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Hodgdon H4350 ?

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 !

Code:

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

-10.0   90    38.70   2542    1722   37564   8257     90.9    1.393
-09.0   91    39.13   2570    1759   38733   8367     91.5    1.372
-08.0   92    39.56   2597    1798   39940   8475     92.0    1.353
-07.0   93    39.99   2625    1836   41184   8581     92.5    1.334
-06.0   94    40.42   2653    1875   42469   8685     93.0    1.315
-05.0   95    40.85   2681    1915   43795   8787     93.5    1.297
-04.0   96    41.28   2709    1955   45163   8888     93.9    1.279
-03.0   98    41.71   2736    1995   46577   8986     94.4    1.261
-02.0   99    42.14   2764    2036   48035   9081     94.8    1.243
-01.0  100    42.57   2792    2077   49534   9175     95.2    1.226
+00.0  101    43.00   2820    2119   51076   9266     95.6    1.209
+01.0  102    43.43   2848    2161   52663   9355     96.0    1.193  ! Near Maximum !
+02.0  103    43.86   2876    2203   54301   9441     96.3    1.176  ! Near Maximum !
+03.0  104    44.29   2903    2246   55992   9524     96.7    1.160  ! Near Maximum !
+04.0  105    44.72   2931    2289   57739   9605     97.0    1.144  ! Near Maximum !
+05.0  106    45.15   2959    2333   59544   9682     97.3    1.129  !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    101    43.00   2959    2334   60388   9335     99.3    1.124  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    101    43.00   2643    1861   42078   8791     88.4    1.317

Your powder charge of 43 grains is a teeny bit above the node, , try to back off a grain and work up in .3 increments.
http://imgur.com/a/kmAUV