300 win load SLOW

F

fwood

Beginner
Jul 15, 2011
164
58
Ok I know this has come up before but here it is. I am shooting a 300 win and tested my loads across the cronograph a cople days ago. I was astonished at how slow they were going. The first one was a 185 g Berger vld hunting bullet, 74.0 grains of H 4831sc with an average velocity of 2823 fps. The second is a 180g NAB with 75g 0f H 4831sc the average velocity here is 2880. Now I can’t argue with result it is ½ in at 100. The gun is a rem 700 bdl stainless with a 24 in barrrel, 28F at 8000 ft.


Hodgdons data
Hodgdon
Powder H4831
Bullet Diameter .308"
C.O.L. 3.285"
Starting Load
Grains 69.0
Velocity (ft/s) 2,851
Pressure 48,500 CUP
Maximum Load
Grains 73.0C
Velocity (ft/s) 2,966 c
Pressure 53,200 CUP

My real numbers are well below their min load? and I am over book based on old data I have used for the last 15 years


Any ideas?

Thanks
 

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QL indicates this to be a relatively mild charge.

Cartridge : .300 Win. Mag....710 3018 46046 11506 91.0 1.332

You might try increasing charge weight in small increments (say 0.5 grains) to see what you get. This is what a 74.7 grain charge is projected to deliver.

Code: 
Cartridge          : .300 Win. Mag.(W)
Bullet             : .308, 185, Berger Hunt VLD G7 #30513
Useable Case Capaci: 81.057 grain H2O = 5.263 cm³
Cartridge O.A.L. L6: 3.285 inch = 83.44 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Hodgdon H4831

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   82    59.76   2359    2287   31420   9532     88.3    1.582
-18.0   84    61.25   2419    2404   33545   9852     89.6    1.542
-16.0   86    62.75   2479    2524   35818  10165     90.9    1.502
-14.0   88    64.24   2539    2648   38245  10469     92.1    1.459
-12.0   91    65.74   2599    2775   40843  10763     93.2    1.414
-10.0   93    67.23   2659    2905   43623  11045     94.2    1.371
-08.0   95    68.72   2720    3039   46602  11315     95.2    1.329
-06.0   97    70.22   2780    3175   49795  11570     96.1    1.289
-04.0   99    71.71   2841    3315   53208  11811     96.9    1.250  ! Near Maximum !
-02.0  101    73.21   2901    3458   56841  12035     97.6    1.212  ! Near Maximum !
+00.0  103    74.70   2962    3604   60733  12242     98.2    1.176  ! Near Maximum !
+02.0  105    76.19   3022    3753   64910  12430     98.7    1.141  !DANGEROUS LOAD-DO NOT USE!
+04.0  107    77.69   3083    3904   69397  12598     99.2    1.108  !DANGEROUS LOAD-DO NOT USE!
+06.0  109    79.18   3143    4058   74224  12745     99.5    1.075  !DANGEROUS LOAD-DO NOT USE!
+08.0  111    80.68   3203    4215   79423  12869     99.8    1.043  !DANGEROUS LOAD-DO NOT USE!
+10.0  113    82.17   3263    4374   85033  12971     99.9    1.013  !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    103    74.70   3097    3941   72204  12034    100.0    1.092  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    103    74.70   2780    3176   49614  11835     92.3    1.285

Code: 
Cartridge          : .300 Win. Mag.(W)
Bullet             : .308, 180, Nosler AccuBond 54825
Useable Case Capaci: 80.603 grain H2O = 5.233 cm³
Cartridge O.A.L. L6: 3.285 inch = 83.44 mm
Barrel Length      : 24.0 inch = 609.6 mm
Powder             : Hodgdon H4831

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   83    60.00   2384    2271   31367   9467     87.6    1.563
-18.0   85    61.50   2444    2388   33503   9789     89.0    1.523
-16.0   87    63.00   2505    2509   35787  10104     90.3    1.484
-14.0   89    64.50   2566    2633   38231  10410     91.5    1.441
-12.0   91    66.00   2628    2760   40848  10706     92.7    1.396
-10.0   93    67.50   2689    2891   43649  10991     93.8    1.354
-08.0   96    69.00   2751    3025   46657  11263     94.8    1.312
-06.0   98    70.50   2813    3163   49883  11522     95.7    1.272
-04.0  100    72.00   2875    3303   53349  11766     96.5    1.233  ! Near Maximum !
-02.0  102    73.50   2937    3447   57055  11993     97.3    1.196  ! Near Maximum !
+00.0  104    75.00   2999    3594   61015  12203     98.0    1.160  ! Near Maximum !
+02.0  106    76.50   3061    3744   65270  12394     98.5    1.125  !DANGEROUS LOAD-DO NOT USE!
+04.0  108    78.00   3123    3897   69848  12565     99.0    1.091  !DANGEROUS LOAD-DO NOT USE!
+06.0  110    79.50   3184    4053   74781  12715     99.4    1.058  !DANGEROUS LOAD-DO NOT USE!
+08.0  112    81.00   3246    4212   80105  12842     99.7    1.027  !DANGEROUS LOAD-DO NOT USE!
+10.0  114    82.50   3308    4373   85859  12946     99.9    0.997  !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    75.00   3138    3937   72641  12031    100.0    1.076  !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba    104    75.00   2813    3162   49813  11762     91.8    1.268

You are still generating a pretty fierce blow with your current velocities. I wouldn't be terribly upset with good accuracy at those velocities.
 
Thanks Mike for the great data! My thought are it is shooting great but, I will bump it up just slightly and see where I am at. We are only talking 3 inches at 500 yards.

Jon
 
Those velocities aren't great but your accuracy is nothing to sneeze at.
Accuracy is the most important thing in my opinion. Dr Mike is right, try increasing the charge weight in small increments. You might find a charge as good or better but if you don't I wouldn't sweat it.

Vince

Sent from my SGH-M919 using Tapatalk
 
My load is 76 gr of H4831 for 180 gr since 1993.
 
IMR7828 can get you a bit more velocity. Or H1000. But you might not get any better accuracy. Is 50-75fps Worth the headache?
 
In my 300, based on ballistics I am getting about 3000, with a 180 PT, with similar accuracy. Fiddle with it as you suggest, but I know for a fact that the animals you shoot with it will never know the difference.
 
Tanks for the input, I am going to fiddle with a little more powder, and agree that it will be hard to get any better accuracy. The animals in the past did not know that the things were running a little slow, before I knew the velocity's. Thanks again.

Jon
 
Sometimes we confound ourselves with too much information.

Sent from my SGH-M919 using Tapatalk
 
fwood":1yc9qyfz said:
The first one was a 185 g Berger vld hunting bullet, 74.0 grains of H 4831sc with an average velocity of 2823 fps. The second is a 180g NAB with 75g 0f H 4831sc the average velocity here is 2880. Now I can’t argue with result it is ½ in at 100. The gun is a rem 700 bdl stainless with a 24 in barrrel, 28F at 8000 ft.


Any ideas?

Thanks
Click to expand...
One thing I deal with is my rem 700 270 win is much slower then book velocity, like 200fps below Nosler velocities. I think it has something to do with the extremely long throat of the factory chamber.

But I get great accuracy! I just can't seat bullets anywhere near the lands, and I get much slower velocity.
 
Some of the REMs certainly do have long throats and it definately tames things down as the entire combustion chamber is now roomier.
I'm betting you can keep working up to the velocities in the ql predictions w/o pressure problems.
I have a 300 win tikka with much the same results.
 
fwood":1kq69emz said:
Tanks for the input, I am going to fiddle with a little more powder, and agree that it will be hard to get any better accuracy. The animals in the past did not know that the things were running a little slow, before I knew the velocity's. Thanks again.

Jon
Click to expand...

Chronographs have ruined more good loads than any of us can imagine. :grin:
 
kraky":26ca5x0d said:
I have a 300 win tikka with much the same results.
Click to expand...

Every tikka I have loaded for has been kn the slow side! They all shot good but would require over max loads to get close to book speeds.


Sent from my iPhone using Tapatalk
 
Well I did some tinkering and things got a little faster, I was able to pick up 100 fps and keep the groups tight. All are 4 rounds, from 74.5-75.5 top speed was 2931 average. I think my flinch was on display, as I was shooting the 338 rum today as well.

Jon

ATTACH]
 
Your velocity is pretty good and the groups (especially at the stiffer charge) aren't at all bad. That may be a matter of seating depth. The VLDs tend to like being close to the lands in my experience.
 
When my loads are "slow" there are a few things that are usually to blame.. Temperature below standard, H2O capacity of the brass above standard, and seating depth longer than the recipe calls for. Those three things can all make for large differences in velocity.
 
Well this is good enough for right now. 3/4" is fine with me 2930 is pretty fast and I cant complain about what it has always done on the far end to Deer and Elk. I am going to take my 20 year old leupold off and send it in for a CDS turret. Last time I checked it was about $150.00. With a 200 zero it should be pretty effective out past 500. The 338 Rum with the same set up is hitting the 12 inch, dinger at 600 all day.

Jon
 
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