.257Wby range test

[boomer68]

Got a chance to head out to the range yesterday and tried out some 110gr AB in my .257 Wby and here are the results

Not too good. I am wondering if I should try another powder?
There was no pressure signs on the 70gr load. Should I try going up in charge or ??

 

[Jerry 919]

Built my .257 this winter. Brand new Ruger M77VT 26" barrel .25-06 and had it re-chambered, bolt face modified and considerable stock re-configuration.

I have spent considerable time developing a 100 grain Ballistic Tip and 110 AccuBond load. This caliber will truly amaze you. I have used the Ballistic Tip load on coyotes here in Central Oregon and the AccuBond load only on paper. Shot (5) coyotes this week from 100 to 400 yards. It kills like lightning. If you can tell it is a coyote with the naked eye you can kill it.

At the range if I do my part I'll hit the 500 yard metal gong every time. Both load have (3) shot groups right at .25" at 100 yards.

Many hours and appropriate caution were used to develop these loads. Most reloaders will advocate maximum overall length for best accuracy. With this caliber this made accuracy worse. I have had the best luck staying close to factory specification of 3.17 to 3.18" overall length.

Each rifle is different so please work up slowly and check for pressure signs at each step. Don't take anything for granted. Assume nothing.

Here are the loads:

Norma Brass, 215 Federal Magnum primers, 76.5 grains Retumbo, 100 grain Nosler Ballistic Tip, 3625 FPS. Three rounds touching at 100 yards, and (11) coyotes so far this year.

Norma Brass, 215 Federal Magnum primers, 71.0 grains 7828 SSC, 110 grain Nosler AccuBond, 3400 FPS. Three rounds touching at 100 yards.

The Ballistic Tip load is NOT fur friendly. I will have my partner, Kirt, post a picture of a double on May 29th.

Good luck and enjoy.

Jerry

 

[boomer68]

Thanks Jerry for the loads. I will give 7828SSC a try.

Ian

 

[300winnie]

Boomer 68

What were your velocities?

The reason I ask is that I am using RL25 and the 110 AccuBond, but I am at 74 grains of powder for 3,525 fps. Wondering if you still have some room to experiment.

 

[remingtonman_25_06]

Looks like you need to do a little more testing...

I'd load up a few loads in 1g increments to start untill you find something that shoots around 1", then fine tune in .5g increments or smaller.

Trying to find a load with just 1 combo doesn't always work...

I see you used 68g RL-25, and 70g RL-25. Now you can totally skip a "accuracy node" in 2g of difference...What you need to do is load up 3 shells with about 5-6 different powder charges. From say 67-71 in .5g increments. Then you'll have about 10 loads to shoot, and 1 of them should shoot .75" or better, usually.

 

[wingnut]

Jerry's pair:

 

[boomer68]

Boomer 68

What were your velocities?

The reason I ask is that I am using RL25 and the 110 AccuBond, but I am at 74 grains of powder for 3,525 fps. Wondering if you still have some room to experiment.

I didn't take my Chrony, so not sure of velocities. I might need to bump the 70gr load up in 1gr increments as no pressure signs were seen. I did pick up some 7828SSC on the weekend, so will try it also.
Anyone have a good starting load for it? Can't find any data.

 

[wingnut]

Boomer68-

You can always reduce Jerry's load by 5% (to 66g) or use a simular powder's starting point such as H1000 at 67g per IMR's recommendation for a 115g bullet on Hodgdon's website.

 

[boomer68]

wingnut,

I will give that a try. Hope to head out to the range on Sat and we shall see what happens.

Regards

Ian

 

[FOTIS]

Cartridge : .257 Weath. Mag
Bullet : .257, 110, BER
Cartridge O.A.L. L6: 3.170 inch or 80.52 mm
Barrel Length : 26.0 inch or 660.4 mm
Powder : Alliant Reloder-22

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 75 54.40 2780 1887 32866 11649 93.5 1.584
-18.0 77 55.76 2848 1981 35099 11994 94.6 1.545
-16.0 79 57.12 2917 2078 37460 12324 95.7 1.505
-14.0 81 58.48 2985 2176 39966 12635 96.7 1.459
-12.0 83 59.84 3053 2276 42627 12927 97.5 1.414
-10.0 85 61.20 3120 2378 45452 13197 98.2 1.372
-08.0 87 62.56 3187 2481 48451 13445 98.8 1.331
-06.0 88 63.92 3254 2586 51634 13669 99.3 1.292
-04.0 90 65.28 3320 2692 55014 13868 99.7 1.253 ! Near Maximum !
-02.0 92 66.64 3385 2799 58602 14040 99.9 1.217 ! Near Maximum !
+00.0 94 68.00 3450 2908 62415 14184 100.0 1.182 ! Near Maximum !
+02.0 96 69.36 3514 3017 66467 14305 100.0 1.149 !DANGEROUS LOAD-DO NOT USE!
+04.0 98 70.72 3578 3126 70775 14421 100.0 1.116 !DANGEROUS LOAD-DO NOT USE!
+06.0 100 72.08 3640 3237 75359 14533 100.0 1.085 !DANGEROUS LOAD-DO NOT USE!
+08.0 102 73.44 3702 3348 80239 14641 100.0 1.055 !DANGEROUS LOAD-DO NOT USE!
+10.0 104 74.80 3764 3460 85439 14745 100.0 1.026 !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 94 68.00 3586 3141 74237 13712 100.0 1.094 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 94 68.00 3250 2581 50660 14233 96.9 1.299



Cartridge : .257 Weath. Mag
Bullet : .257, 110, BER
Cartridge O.A.L. L6: 3.170 inch or 80.52 mm
Barrel Length : 26.0 inch or 660.4 mm
Powder : Alliant Reloder-25

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 79 56.00 2772 1877 31116 11777 96.8 1.604
-18.0 81 57.40 2842 1972 33267 12085 97.8 1.564
-16.0 83 58.80 2911 2069 35585 12365 98.6 1.524
-14.0 85 60.20 2979 2168 38059 12615 99.2 1.482
-12.0 87 61.60 3048 2268 40709 12833 99.6 1.436
-10.0 89 63.00 3115 2370 43548 13018 99.9 1.391
-08.0 91 64.40 3182 2472 46592 13167 100.0 1.348
-06.0 93 65.80 3247 2575 49855 13297 100.0 1.307
-04.0 95 67.20 3312 2679 53358 13424 100.0 1.267
-02.0 97 68.60 3376 2783 57076 13547 100.0 1.229 ! Near Maximum !
+00.0 98 70.00 3439 2888 61031 13666 100.0 1.193 ! Near Maximum !
+02.0 100 71.40 3501 2994 65248 13782 100.0 1.158 !DANGEROUS LOAD-DO NOT USE!
+04.0 102 72.80 3563 3101 69746 13894 100.0 1.124 !DANGEROUS LOAD-DO NOT USE!
+06.0 104 74.20 3624 3208 74549 14001 100.0 1.092 !DANGEROUS LOAD-DO NOT USE!
+08.0 106 75.60 3685 3317 79680 14105 100.0 1.060 !DANGEROUS LOAD-DO NOT USE!
+10.0 108 77.00 3745 3427 85167 14204 100.0 1.030 !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 98 70.00 3565 3105 74170 13230 100.0 1.100 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 98 70.00 3245 2573 48387 14181 99.4 1.317

 

[boomer68]

POP

What software are you using to generate that data?

 

[300winnie]

Boomer68,

I know you are already aware of this, but each rifle is an individual, so with that said you will need to take my findings and use your own common sense on what your rifle/load tells you.

With that said my load referenced above consists of the following:

Winchester brand 7mm Remington Magnum Brass - Sized through RCBS .257 Weatherby FL Sizing die for a crush fit.
Federal 215M Primer
Nosler 110 grain AccuBond - seated out to maximum magazine function
74.0 grains of RL25

This load chronographs right at 3,525 fps - 15 ft from muzzle...obviously max loading, but no apparent signs of pressure and the primer pockets are not noticeably loosening. Here is a couple of groups I have fired on different days with this load.

As far as where to start with IMR 7828SSC I can only give you my experience with that powder (at least the long cut version). I use it with 115 grain Ballistic Silvertips and I get 3,400 fps with 70.0 grains of that powder when using 7mm Remington Magnum brass. When I used that load with Weatherby brass it took 71.0 grains to get the same velocity.

Hope this helps.[/img]

 

[wingnut]

2 more from Jerry:

110g AccuBond

100g BT

 

[FOTIS]

I am using Quickload. It is a pretty good reference.

 

[300winnie]

Impressive...it looks like Jerry has it working for him. Especially like the holes in those coyotes. Are those BT's or AB's?

I shot one with a 115 CTBST...looks about the same.

 

[Jerry 919]

Both coyotes were with the 100 grain Ballistic Tip. First was at about 150 and the second was about 200 yards. Both instant flop. Actually saw the second one come off the ground and get thrown about three feet sideways.

Jerry

 

[boomer68]

Maybe I was seating the bullet out too far? My COL was 3.250" and I noticed in Quickloads it is 3.170".

Ian

 

[Jerry 919]

Boomer,

When I first started playing with this caliber I seated out to 3.25". Groups started out poorly and velocity was less than desired. Got some real good info and insight in this forum and read everything I could find on the internet. Read a couple of things. Select slowest powder and get the highest density as possible. Second thing was an article by Layne Simpson about the .257 Weatherby. He also was at maximium length and then return to factory specification and found the desired accuracy and velocity.

I was working with 100BT and Retumbo and it showed promise around 75 and 75.5 grains. Went back to 3.17" length. Magic! .5" groups at 76.0 grains consistently. Less than one inch at 200 and whack metal gongs to 500 yards with ease.

I have mine sighted in 3 inches high at 100, and it is dead-on at 300 yards. Velocity is 3625 FPS. Kills like lightning.

Jerry

 

[boomer68]

Jerry,

I might try RL25 again, and try different seating depths. So many variables

 

[Jerry 919]

I have read that RL25 is a good powder for the caliber. I always try to stick with Hodgdon Extreme powders. They are less temperature sensitive and temperature get pretty cold here in winter, anywhere from 0 to 30 degress and hot in the summer, 90-100. Ost shooting is in the cold months but loads are still within reason in the warmer months.

If you have a wide range of temps, and particularly cold in Alberta, I would suggest staying with Hodgdon powders. I have found too much pressure spread in the RL powders. They are great if you have stable moderate temperatures.

Jerry