280 Rem - QL Request

[M7025-06]

I don't have a computer with my QL installed on it anymore (I'm waiting on an external dvd drive to show up). While I'm waiting could someone run some quick numbers for me?

I included the velocity I got with a Magnetospeed last trip out if that helps to match things up. I'm curious to see where I'm at for pressure due to the lower than expected velocities I'm getting.
TIA.

280 Rem
23'' barrel
140 gr. AccuBond
COAL: 3.373'' (seated 0.020'' off lands)
1-fired Winchester brass (71.24 gr. H2O capacity)
56.0 gr. IMR-4831 @ 2838 fps (75* at the time)

 

[DrMike]

Cartridge          : .280 Rem.
Bullet             : .284, 140, Nosler AccuBond 59992
Useable Case Capaci: 64.121 grain H2O = 4.163 cm³
Cartridge O.A.L. L6: 3.373 inch = 85.67 mm
Barrel Length      : 23.0 inch = 584.2 mm
Powder             : IMR 4831

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    44.80   2354    1722   28676   9127     92.4    1.534
-18.0   81    45.92   2411    1808   30544   9404     93.6    1.499
-16.0   83    47.04   2469    1895   32522   9670     94.6    1.463
-14.0   85    48.16   2526    1984   34623   9926     95.6    1.428
-12.0   87    49.28   2584    2075   36854  10169     96.5    1.394
-10.0   89    50.40   2641    2168   39223  10398     97.2    1.352
-08.0   91    51.52   2698    2262   41737  10613     97.9    1.312
-06.0   93    52.64   2754    2358   44406  10812     98.5    1.274
-04.0   95    53.76   2811    2456   47241  10995     99.0    1.237
-02.0   97    54.88   2867    2554   50252  11160     99.4    1.202  ! Near Maximum !
+00.0   99    56.00   2922    2654   53451  11306     99.7    1.168  ! Near Maximum !
+02.0  101    57.12   2977    2756   56851  11434     99.9    1.135  ! Near Maximum !
+04.0  103    58.24   3032    2858   60468  11542    100.0    1.104  !DANGEROUS LOAD-DO NOT USE!
+06.0  105    59.36   3086    2961   64317  11633    100.0    1.073  !DANGEROUS LOAD-DO NOT USE!
+08.0  107    60.48   3140    3065   68416  11719    100.0    1.044  !DANGEROUS LOAD-DO NOT USE!
+10.0  109    61.60   3193    3170   72785  11802    100.0    1.016  !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    56.00   3046    2884   64034  10894    100.0    1.080  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba     99    56.00   2745    2342   43100  11219     95.4    1.285

 

[Horsethief]

If you can, run the 140gn Accubonds with Superformance. I've had great accuracy with that powder in 140 and 150 grain bullets. Bang-flop results on a big White tail buck, too.

H-4350 is just as good with the 140gn bullets as the SF (in my 280). Good luck.

 

[M7025-06]

Thanks Dr. Mike! I appreciate it.

I'll give that some thought Horsethief. What kind of velocities are getting?

 

[6mm Remington]

IMR4350 & 54.0 grs. with a 140 gr. Partition gave me 3/4" groups at 100 yards and 2940 fps out of a 22" barrel. Played a little with it and H4831SC and magnum primers worked very well also, but I already had a great load so I just stayed with it.

 

[M7025-06]

IMR4350 & 54.0 grs. with a 140 gr. Partition gave me 3/4" groups at 100 yards and 2940 fps out of a 22" barrel. Played a little with it and H4831SC and magnum primers worked very well also, but I already had a great load so I just stayed with it.

I've got both of those powders on the shelf so I might give them a go.

56 gr. of IMR-4831 has my go to load for about a year and, according to my old shooting chrony, was giving me 2950 fps, so I'm a little surprised by the low velocity according to the Magnetospeed.

 

[Horsethief]

M7025-06: 140gn Nosler BT with 58gn SF gave me from 3104 to 3143fps from a 24" barrel. I got from 2988 to 3018 with the same amount of powder in the 140gn Sierra Game Kings. I'm guessing the warmer barrel and higher BC of the Nosler bullet enables it go faster. The new chronograph was used for these readings.

57gn of SF in the 150gn Sierra Game King clocked 2975fps on the old chronograph. It also shot a 2.4" group at 400 yards in the picture. This is not a target rifle turned into a hunting rifle. Its a pure hunting rifle.