Quickload Request Please

[HeathSexton]

375 Winchester- Marlin 336 Big Bore -20" barrel

WW Brass - .375 Winchester
IMR-4198
200gr Sierra FP
CCI200


Thanks!

 

[RiverRider]

Cartridge          : .375 Win.
Bullet             : .375, 200, Sierra SPFN 2900
Useable Case Capaci: 39.860 grain H2O = 2.588 cm³
Cartridge O.A.L. L6: 2.560 inch = 65.02 mm
Barrel Length      : 20.0 inch = 508.0 mm
Powder             : IMR 4198

Predicted data by increasing and decreasing the given charge,
incremented in steps of 0.179% 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

-01.8  111    36.44   2378    2512   50626   5005     97.9    1.007  
-01.6  111    36.50   2382    2520   50907   5012     98.0    1.004  
-01.4  111    36.57   2386    2529   51190   5019     98.0    1.002  
-01.3  111    36.64   2390    2537   51473   5026     98.1    1.000  
-01.1  111    36.70   2394    2546   51753   5033     98.1    0.997  
-00.9  112    36.77   2398    2554   52046   5040     98.1    0.995  
-00.7  112    36.83   2402    2562   52335   5046     98.2    0.993  
-00.5  112    36.90   2406    2571   52626   5053     98.2    0.990  
-00.4  112    36.97   2410    2579   52918   5060     98.3    0.988  
-00.2  112    37.03   2414    2588   53211   5066     98.3    0.986  
+00.0  113    37.10   2418    2596   53509   5073     98.4    0.984  
+00.2  113    37.17   2422    2605   53806   5079     98.4    0.981  
+00.4  113    37.23   2426    2613   54106   5086     98.4    0.979  
+00.5  113    37.30   2430    2622   54407   5092     98.5    0.977  
+00.7  113    37.37   2434    2630   54711   5098     98.5    0.975  
+00.9  114    37.43   2438    2639   55016   5105     98.6    0.973

Warnings usually seen have been edited out for readability's sake. I believe the SAAMI max is 55000 psi.

 

[HeathSexton]

Thanks!


Looks like I've got room to move up. I found some info that topped out at 34.5grs. I'm at 33.0grs right now.

 

[RiverRider]

You're most welcome. Would you feel more comfortable (I know I would) if we ran the load using your actual case capacity?

 

[HeathSexton]

If I did it correctly, filled a case up with water, I got 48.8grs.

 

[RiverRider]

Okay, that actually gave you a bit more headroom, I think. Here's what QL thinks:

Cartridge          : .375 Win.
Bullet             : .375, 200, Sierra SPFN 2900
Useable Case Capaci: 40.665 grain H2O = 2.640 cm³
Cartridge O.A.L. L6: 2.560 inch = 65.02 mm
Barrel Length      : 20.0 inch = 508.0 mm
Powder             : IMR 4198

Predicted data by increasing and decreasing the given charge,
incremented in steps of 0.176% 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

-01.8  110    37.04   2397    2552   51001   5095     98.2    1.002  ! Near Maximum !
-01.6  110    37.10   2401    2560   51277   5102     98.2    0.999  ! Near Maximum !
-01.4  111    37.17   2405    2568   51557   5109     98.2    0.997  ! Near Maximum !
-01.2  111    37.24   2409    2577   51837   5115     98.3    0.995  ! Near Maximum !
-01.1  111    37.30   2413    2585   52119   5122     98.3    0.993  ! Near Maximum !
-00.9  111    37.37   2417    2593   52402   5129     98.4    0.990  ! Near Maximum !
-00.7  111    37.43   2420    2602   52687   5135     98.4    0.988  ! Near Maximum !
-00.5  112    37.50   2424    2610   52975   5142     98.5    0.986  ! Near Maximum !
-00.4  112    37.57   2428    2619   53262   5148     98.5    0.984  ! Near Maximum !
-00.2  112    37.63   2432    2627   53552   5155     98.5    0.982  ! Near Maximum !
+00.0  112    37.70   2436    2635   53846   5161     98.6    0.979  ! Near Maximum !
+00.2  112    37.77   2440    2644   54141   5167     98.6    0.977  ! Near Maximum !
+00.4  113    37.83   2444    2652   54436   5174     98.6    0.975  !DANGEROUS LOAD-DO NOT USE!
+00.5  113    37.90   2448    2661   54733   5180     98.7    0.973  !DANGEROUS LOAD-DO NOT USE!
+00.7  113    37.97   2452    2669   55033   5186     98.7    0.971  !DANGEROUS LOAD-DO NOT USE!
+00.9  113    38.03   2455    2678   55333   5192     98.8    0.968  !DANGEROUS LOAD-DO NOT USE!

I've looked at a few data sources to compare to QL's result. There ain't much for a 200-grain jacketed bullet out there, is there? About 35, maybe 36 grains max seems about right to me based on what little I've been able to find...yet, here is QL saying something else. I think what I'd do is a little research to see if 2400 fps is reasonable for the combination, and then put the chronograph to work, and I would not exceed it PROVIDED that seems to be a reasonable velocity with the 200 grainer. I wouldn't blame you a bit though if you decided to keep it milder than that. I just don't know, myself.

What do you think?

 

[HeathSexton]

I've looked at a few data sources to compare to QL's result. There ain't much for a 200-grain jacketed bullet out there, is there? About 35, maybe 36 grains max seems about right to me based on what little I've been able to find...yet, here is QL saying something else. I think what I'd do is a little research to see if 2400 fps is reasonable for the combination, and then put the chronograph to work, and I would not exceed it PROVIDED that seems to be a reasonable velocity with the 200 grainer. I wouldn't blame you a bit though if you decided to keep it milder than that. I just don't know, myself.

What do you think?

Thanks again.

Yeah finding info has been tougher than I figured. Sierra says 34.6grs is tops, I saw a few places where 33.0grs IMR4198 is 2050-2100fps and H4198 data is 38.0grs as max around 2400fps.

I will chrono the 33gr load soon and go from there. I shot 2 different 3 shot groups at 110yds today with a Leupold 1-4x20 heavy duplex that averaged 1" so if nothing else it's good where it is.