What do you think of this load?

FOTIS

Range Officer
Staff member
Oct 30, 2004
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3,186
A little concerned about the speed.... 115 Nosler Partition








Code:
Cartridge          : .257 Weath. Mag
Bullet             : .257, 115, Nosler PART SP 16318
Useable Case Capaci: 77.120 grain H2O = 5.007 cm³
Cartridge O.A.L. L6: 3.170 inch = 80.52 mm
Barrel Length      : 26.0 inch = 660.4 mm
Powder             : IMR 7828 SSC

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   83    60.75   3087    2434   45570  13361     97.6    1.374
-09.0   84    61.43   3121    2488   47106  13495     98.0    1.353
-08.0   85    62.10   3155    2542   48691  13624     98.3    1.332
-07.0   86    62.78   3189    2597   50334  13746     98.6    1.312
-06.0   87    63.45   3223    2653   52023  13861     98.9    1.292
-05.0   88    64.13   3257    2709   53760  13970     99.2    1.272
-04.0   89    64.80   3291    2765   55548  14073     99.4    1.253  ! Near Maximum !
-03.0   90    65.48   3324    2822   57394  14168     99.6    1.234  ! Near Maximum !
-02.0   91    66.15   3358    2879   59299  14256     99.7    1.216  ! Near Maximum !
-01.0   92    66.83   3391    2936   61266  14336     99.8    1.198  ! Near Maximum !
+00.0   92    67.50   3424    2994   63297  14409     99.9    1.180  !DANGEROUS LOAD-DO NOT USE!
+01.0   93    68.18   3457    3051   65395  14474    100.0    1.163  !DANGEROUS LOAD-DO NOT USE!
+02.0   94    68.85   3490    3110   67561  14532    100.0    1.146  !DANGEROUS LOAD-DO NOT US
 
Great group, great velocity.

Don't think I'd want to use 'em in 100 degree weather...

Guy
 
Fotis, Noslers book shows 69g at 3433 fps and I was loading 70g in mine with no ejector marks or other pressure signs. Velocity was 3500fps same as factory loads in my barrel. Gun was markv big game master with hand lapped barrel.
 
Forgot to add that I used this load in temps ranging from 20 degrees to 90 degrees and did not see any difference.
 
I think its maybe a grain or so on the heavy side, I don't like the "deep" firing pin strike, it looks like they are cratering a bit to much for my comfort. Is that your Antelope load? Like you I would be also concerned about the performance of any bullet of that weight going that fast. Plenty accurate however.
 
Looks like well used brass. Are the pockets getting loose?

I agree on the firing pin mark, but can’t be sure the reason is the load is hot vs pocket loose

Fotis, really fine shooting. If you taught classes, I’d come out at take them.

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Elkman":3luckyyg said:
I think its maybe a grain or so on the heavy side, I don't like the "deep" firing pin strike, it looks like they are cratering a bit to much for my comfort. Is that your Antelope load? Like you I would be also concerned about the performance of any bullet of that weight going that fast. Plenty accurate however.


First thing that stood out to me. Not saying it's overboard but it's got some peculiarity's I'm not used to seeing.
 
That sure is a nice group at a smoking speed! I have no clue if it’s too hot or not but dang that’s tight and fast lol.


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It's a load with pressure! That said if it doesn't ruin primer pockets in a couple firings I wouldn't be afraid of it for hunting purposes. Obviously not a high volume varmint load. Accuracy is gr at and that ll hit hard.

As an FYI I m using 67.5 grs of R22 with 115 BT and getting 3350-3375 fps with a 26" barrel. It's no doubt developing plenty of pressure also. Primer pockets still ok at 3 rd loading but not going to be brass that lasts 8-10 shots.

Good luck and let us know what you decide. IMR 7828 has always gotten great velocity in the Weatherbys but they ve never been 'conservative' !
 
Brass is used for sure. I think I might come down a grain or two just to be on the safe side the book does show 3350 with a 120 Partition so another hundred feet per second with a 115 should be but I will play it safe
 
Looks great! I have an Accumark I've had for 15-20 years. It pissed me off and I haven't shot it in years. A two together and one way off rifle. Maybe I'll did it out and try it again.
 
https://load-data.nosler.com/load-data/ ... by-magnum/







The book says 69 gr 7828 at 3433.
I am using 67.5 at 3460 or so. Primers always look like that regardless of what I shoot through it.
Brass holds up very well thus far. Anyway I will tweak it with a lower charge just for safety's sake
 

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Fotis, because it is well-used brass, it's hard to tell. I was looking at the brass and headstamps more than the primers. Some brass has sharp lettering, some has more rounded, one has a weird mark. If I were playing with it, I'd lightly polish the headstamps with fine steel wool in a circular pattern, then number the cases with a Sharpie. Then take before and after pictures of each of the numbered ones, looking for marks, flattening of the printing, or anything else that looks like pressure is hitting that end. Wish we all had pressure testing equipment!
EE2
 
According to the date on your target analysis, this load is from the future ... that is another special capability of the Weatherby calibers.

I exclusively use 7828SSC in my Weatherby calibers with similar results to you. I will be tuning up a 6.5-300 soon and I will try it there, too.
 
I have a Remington M700 BDL I bought NIB and it craters like that even with light cast bullet loads. It appears that some idiot at the factory chamfered the firing pin hole in the face of the bolt so everything I shoot in that one gives me a cratered primer. I've shot loads as hot as 58.0 gr. of H4350 and the 180 gr. Hornady SP. Same load shoots just fine in an M700 Classic in 30-06. No obvious pressure signs in either rifle. Primers appear flattened but not top hat flat, slight cratering probably more due to a slightly oversized hole in the bolt face. FWIW, the velocity from both rifles ran slightly above 2800 FPS from a 22" barrel. I agree that's pushing the old 06 but I was curious as to how far I could go. Temp was in the mid 90's as I recall.
Paul B.
 
rodell":3u2fpkn1 said:
According to the date on your target analysis, this load is from the future ... that is another special capability of the Weatherby calibers.

I know I know! :oops:
 
That load is smoking and with no marks from ejector marks on the brass I would just load them up and go hunting any Antelope or Deer. I would hate to loose any accuracy.
I would watch them when temperature is warmer.
That is some good shooting FOTIS do you put on a higher powered scope for your load testing ?
 
No . I have the 3x15 SWFA SS on it permanently.
 
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