Quickload info request

[quigley257]

I'm asking for some assistance. I know an individual who shoots the following load through a 26" 338 Lapua Mag and chronos the load at 2961fps average. After researching online I am unable to find a similar load. The load in question just seems way too hot although he claims that it shows no pressure signs and shoots 0.5" at 100 yards. I have seen the targets and the accuracy claims are legitimate. I would appreciate if someone would run this info through Quickload and reply with velocity and pressure predictions. I'm not comfortable shooting with people who disregard load data. Thanks for your time. -Quigley

Lapua Brass
250gr Sierra MatchKing
Rem 9.5M primer
85.0gr IMR4350
OAL 3.640"

 

[jimbires]

this is using the default water capacity . it looks like 79.0 should be about a max load using your specs . and would give 2780 FPS at 61018 PSI . the lapua is rated at 60916 psi .

85.0 grains would be 2951 FPS at 75561 psi . our velocities are very close , so the pressures should be too .

 

[Rhett Crider]

74025 PSI

 

[Broken arrow]

I just eyeballed your data and figured it should be feasible given I'm shooting 300 grain Sierras at 2794. I just pulled my Sierra manual and it shows several 250 grain loads in excess of 3000 FPS. Hell don't take my word for it, here you go

 

[Broken arrow]

He's only shooting 0.5 grain more than the max load. If you cross reference several manuals (I have 8) you'll find multiple variation of the max load. I most generally start my load mid pack and then proceed up ward in 1/2 grain increments until signs of high pressure develope and then I back it back down to no signs of high pressure.

 

[284saum]

I adjusted start pressure to 5000psi (equivalent to .200" freebore) to get 2960 fps

Cartridge          : .338 Lapua Mag.
Bullet             : .338, 250, Sierra HPBT MatchK 2650
Useable Case Capaci: 93.978 grain H2O = 6.102 cm³
Cartridge O.A.L. L6: 3.640 inch = 92.46 mm
Barrel Length      : 26.0 inch = 660.4 mm
Powder             : IMR 4350

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   89    76.50   2719    4103   57557   9625    100.0    1.348  ! Near Maximum !
-09.0   90    77.35   2744    4178   59289   9681    100.0    1.330  ! Near Maximum !
-08.0   91    78.20   2768    4254   61071   9735    100.0    1.312  !DANGEROUS LOAD-DO NOT USE!
-07.0   92    79.05   2793    4329   62906   9789    100.0    1.295  !DANGEROUS LOAD-DO NOT USE!
-06.0   93    79.90   2817    4405   64794   9842    100.0    1.278  !DANGEROUS LOAD-DO NOT USE!
-05.0   94    80.75   2841    4481   66738   9894    100.0    1.261  !DANGEROUS LOAD-DO NOT USE!
-04.0   95    81.60   2865    4557   68740   9946    100.0    1.244  !DANGEROUS LOAD-DO NOT USE!
-03.0   96    82.45   2889    4633   70801   9997    100.0    1.228  !DANGEROUS LOAD-DO NOT USE!
-02.0   97    83.30   2913    4710   72925  10047    100.0    1.212  !DANGEROUS LOAD-DO NOT USE!
-01.0   98    84.15   2937    4787   75112  10097    100.0    1.197  !DANGEROUS LOAD-DO NOT USE!
+00.0   99    85.00   2960    4864   77365  10146    100.0    1.182  !DANGEROUS LOAD-DO NOT USE!
+01.0  100    85.85   2984    4942   79688  10194    100.0    1.167  !DANGEROUS LOAD-DO NOT USE!
+02.0  101    86.70   3007    5020   82081  10241    100.0    1.152  !DANGEROUS LOAD-DO NOT USE!
+03.0  102    87.55   3030    5098   84549  10288    100.0    1.137  !DANGEROUS LOAD-DO NOT USE!
+04.0  103    88.40   3054    5177   87094  10334    100.0    1.123  !DANGEROUS LOAD-DO NOT USE!
+05.0  104    89.25   3077    5256   89718  10379    100.0    1.109  !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    85.00   3031    5099   89065   9848    100.0    1.117  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba     99    85.00   2853    4518   65525  10541     99.7    1.268  !DANGEROUS LOAD-DO NOT USE!

 

[quigley257]

Thanks for the replies. I appreciate the answers. I will try to convince him to try a different, more suitable powder rather than running at the elevated pressures he is gambling with currently.