Unusual QL request?

desertcj · Nov 29, 2015

I already have some test rounds loaded up. Just asking for entertainments sake. .243 Winchester, 26" barrel, 55gr lead free BT, IMR 3031 with an OAL of 2.725". I have test loads from 40gr up to 44gr in 1/2 gr increments, I don't expect to fire them all but I am hoping to find max. This is the powder I had on hand. Not my first round draft pick...lol.

Wyo7200 · Nov 29, 2015

Unusual indeed... "Lead free" changes the initial PSI, not familiar if it is solid copper or soft brass, or normal jacketed. Changes considerably in QL... so here is one of each.

Solid Copper: (6525 psi)

Code:

Cartridge          : .243 Win.
Bullet             : .243, 55, Nosler BTLF 45170
Useable Case Capaci: 50.841 grain H2O = 3.301 cm³
Cartridge O.A.L. L6: 2.725 inch = 69.22 mm
Barrel Length      : 26.0 inch = 660.4 mm
Powder             : IMR 3031

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 !

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

-10.0   87    37.98   3619    1600   47737   7894    100.0    1.059
-09.0   88    38.40   3651    1628   49166   7924    100.0    1.049
-08.0   89    38.82   3682    1655   50638   7953    100.0    1.039
-07.0   90    39.25   3712    1683   52154   7982    100.0    1.029  ! Near Maximum !
-06.0   91    39.67   3743    1711   53715   8010    100.0    1.019  ! Near Maximum !
-05.0   92    40.09   3773    1738   55323   8038    100.0    1.009  ! Near Maximum !
-04.0   92    40.51   3802    1766   56978   8066    100.0    0.999  ! Near Maximum !
-03.0   93    40.93   3832    1793   58683   8093    100.0    0.989  ! Near Maximum !
-02.0   94    41.36   3861    1821   60438   8119    100.0    0.980  !DANGEROUS LOAD-DO NOT USE!
-01.0   95    41.78   3890    1848   62246   8145    100.0    0.970  !DANGEROUS LOAD-DO NOT USE!
+00.0   96    42.20   3919    1876   64107   8171    100.0    0.961  !DANGEROUS LOAD-DO NOT USE!
+01.0   97    42.62   3948    1903   66024   8195    100.0    0.951  !DANGEROUS LOAD-DO NOT USE!
+02.0   98    43.04   3976    1931   67998   8220    100.0    0.939  !DANGEROUS LOAD-DO NOT USE!
+03.0   99    43.47   4004    1958   70032   8244    100.0    0.928  !DANGEROUS LOAD-DO NOT USE!
+04.0  100    43.89   4032    1986   72126   8267    100.0    0.917  !DANGEROUS LOAD-DO NOT USE!
+05.0  101    44.31   4060    2013   74283   8290    100.0    0.906  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 5% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 5% relative to nominal value:
+Ba     96    42.20   3979    1933   69711   8031    100.0    0.930  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 5% relative to nominal value:
-Ba     96    42.20   3846    1806   58504   8341    100.0    0.989  ! Near Maximum !

Normal jacketed (3625 psi):

Code:

Cartridge          : .243 Win.
Bullet             : .243, 55, Nosler BTLF 45170
Useable Case Capaci: 50.845 grain H2O = 3.301 cm³
Cartridge O.A.L. L6: 2.725 inch = 69.22 mm
Barrel Length      : 26.0 inch = 660.4 mm
Powder             : IMR 3031

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 !

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

-10.0   87    37.98   3562    1549   43200   8009     99.9    1.127
-09.0   88    38.40   3595    1578   44622   8042    100.0    1.112
-08.0   89    38.82   3627    1607   46086   8071    100.0    1.096
-07.0   90    39.25   3659    1635   47593   8097    100.0    1.081
-06.0   91    39.67   3691    1664   49145   8123    100.0    1.066
-05.0   92    40.09   3723    1693   50744   8149    100.0    1.052
-04.0   92    40.51   3754    1721   52390   8174    100.0    1.038  ! Near Maximum !
-03.0   93    40.93   3785    1750   54085   8198    100.0    1.024  ! Near Maximum !
-02.0   94    41.36   3816    1778   55830   8223    100.0    1.010  ! Near Maximum !
-01.0   95    41.78   3846    1807   57627   8246    100.0    0.997  ! Near Maximum !
+00.0   96    42.20   3877    1835   59478   8270    100.0    0.984  !DANGEROUS LOAD-DO NOT USE!
+01.0   97    42.62   3906    1864   61384   8292    100.0    0.971  !DANGEROUS LOAD-DO NOT USE!
+02.0   98    43.04   3936    1892   63347   8315    100.0    0.959  !DANGEROUS LOAD-DO NOT USE!
+03.0   99    43.47   3965    1920   65369   8336    100.0    0.946  !DANGEROUS LOAD-DO NOT USE!
+04.0  100    43.89   3995    1949   67452   8358    100.0    0.934  !DANGEROUS LOAD-DO NOT USE!
+05.0  101    44.31   4024    1977   69598   8378    100.0    0.923  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 5% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 5% relative to nominal value:
+Ba     96    42.20   3941    1897   65159   8118    100.0    0.948  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 5% relative to nominal value:
-Ba     96    42.20   3796    1760   53802   8454    100.0    1.026  ! Near Maximum !

Soft brass (1800 psi):

Code:

Cartridge          : .243 Win.
Bullet             : .243, 55, Nosler BTLF 45170
Useable Case Capaci: 50.845 grain H2O = 3.301 cm³
Cartridge O.A.L. L6: 2.725 inch = 69.22 mm
Barrel Length      : 26.0 inch = 660.4 mm
Powder             : IMR 3031

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 !

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

-10.0   87    37.98   3511    1505   39984   8093     99.7    1.155
-09.0   88    38.40   3546    1535   41397   8132     99.9    1.139
-08.0   89    38.82   3580    1565   42852   8166    100.0    1.122
-07.0   90    39.25   3614    1595   44351   8195    100.0    1.106
-06.0   91    39.67   3647    1625   45894   8219    100.0    1.090
-05.0   92    40.09   3680    1654   47484   8243    100.0    1.074
-04.0   92    40.51   3713    1684   49121   8265    100.0    1.059
-03.0   93    40.93   3745    1713   50807   8288    100.0    1.044
-02.0   94    41.36   3777    1743   52543   8310    100.0    1.030  ! Near Maximum !
-01.0   95    41.78   3809    1772   54331   8331    100.0    1.015  ! Near Maximum !
+00.0   96    42.20   3841    1801   56173   8352    100.0    1.002  ! Near Maximum !
+01.0   97    42.62   3872    1831   58070   8373    100.0    0.988  ! Near Maximum !
+02.0   98    43.04   3902    1860   60024   8393    100.0    0.975  !DANGEROUS LOAD-DO NOT USE!
+03.0   99    43.47   3933    1889   62037   8413    100.0    0.962  !DANGEROUS LOAD-DO NOT USE!
+04.0  100    43.89   3963    1918   64111   8433    100.0    0.949  !DANGEROUS LOAD-DO NOT USE!
+05.0  101    44.31   3993    1947   66247   8452    100.0    0.937  !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 5% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 5% relative to nominal value:
+Ba     96    42.20   3910    1867   61891   8191    100.0    0.963  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 5% relative to nominal value:
-Ba     96    42.20   3754    1721   50468   8548    100.0    1.047

desertcj · Nov 29, 2015

Awesome, thank you! I'd say that they are most like normal jacketed bullets, but the bearing surface is much longer than standard 55gr BT's. Did QL actually have the lead free BT in the library? Looks like it. Anyways, even with moly coated bullets it looks like I should be able to find max with my progression up to 44gr.

Wyo7200 · Nov 29, 2015

"BTLF"... I saw it and went for it.

I don't have any experience with them so please report back if you can.

I will later

desertcj · Nov 29, 2015

I will report back with chrono results. I started a thread titled 6mm 55gr lead free a few days back. I was mostly talking about powders to try and there's quite a few good ones for this application, I happened to have IMR 3031 on hand so that trumps most...lol. I may end up buying a few more powders, I want to see how the 3031 plays out first.

desertcj · Dec 5, 2015

Got these tested today and I'm really happy with the results! That's at least 5 shots ranging in velocity from an estimated 3900fps (Chrono didn't read a few shots when the sun came out?) Up to 4127fps!