Help with Favorite 257 Weatherby load

[cb4128]

I am waiting on a custom 257 weatherby to arrive next week (hopefully) and am trying to decide on a custom load to start out with - trying to get around 3,350-3,400 fps with a 110gr accubond with a 26" barrel. Here's what I've come up with, based on what I have on hand right now:

1st load:
Weatherby brass
110gr Nosler Accubond
H1000 powder - between 70-74 (max) grains
Federal 215 primer
or
CCI 250

2nd load:
Weatherby brass
110gr Nosler Accubond
IMR 7828 powder - between 69-71 (max) grains
Federal 215 primer
or
CCI 250

Does anyone else on here have a preferred load they would recommend? Thanks!

 

[cape cove]

I've used the 110 gr AB in my 257 Vanguard with 71 grs of 7828 with a Wea case and a Fed 215 primer. Accuracy was appx MOA and vel was 3348 ft/sec. This is with a 24" barrel, you should have no problem getting the vel you stated with a 26" tube. I've also used the 117 gr Sierra Game king with RL-22. Great powder in this caliber.

 

[Dosh]

cb, several of my friends and I have factory .257 Mark V and Vanguard rifles. We all have found top accuracy with 115 Bergers, H1000 or 7828SSC. None wear Tupperware and all are bedded. Member Az Shooter has the custom .257 WBY dialed in, hopefully he'll submit his experience to this thread. You'll enjoy your new custom .257 Wby.

 

[okie man]

i shoot the 120 grain speer btsp with 67.5 grains of imr7828 . sub moa all day every day

 

[cacsrx1]

115 grain BERGER and H1000

 

[AZShooter]

Four of the six 257 weatherby owners, use RL-25 with the 115 Berger. All these rifles used the same custom reamer and a 3 groove lilja with lengths of 26-28" long.

I see no reason for not trying RL-25 with the 110. Pet loads with moly coated 115 VLDs are 74-74.5 grains of RL-25 DO NOT TRY THIS WITHOUT MOLY COATING!. Nosler suggests 72 as the max load for uncoated 115 ballistic tips. I would say start at 69 gr and work up.

Another powder is RL-33. When it first came out I tried it with 110 Accubonds. Again moly coated.

DETAILS FROM MY DOCUMENTS:

257 Weatherby 28" SS 3 groove Lilja, moly 110 accubond. Barrel now has over 750 rounds through it and throat is quite worn which can lower pressures. Just saying this rifle is most likely not the same as yours so powder charge weights will most likely require less powder. In addition a custom reamer was used which has a shorter throat and different throat angle.

Original load with moly 110 accubonds 75.5 gr of RL-25 vel 3614 fps



83 3625 which slightly faster than old load with RL-25
83.5 3674 fps shot
84 gr 3704 fps shot
84.5 gr 3735 slight signs of pressure on one case of four this is max case capacity with drop tube

I WOULD SUGGEST YOU START WITH 75 GR OF RL-33 AND WORK UP.

 

[cb4128]

excellent info guys, thanks! I may have to get some bergers and one of these other powders to try out. Seems like 3,400 fps is a walk in the park

 

[Nomosendero]

Four of the six 257 weatherby owners, use RL-25 with the 115 Berger. All these rifles used the same custom reamer and a 3 groove lilja with lengths of 26-28" long.

I see no reason for not trying RL-25 with the 110. Pet loads with moly coated 115 VLDs are 74-74.5 grains of RL-25 DO NOT TRY THIS WITHOUT MOLY COATING!. Nosler suggests 72 as the max load for uncoated 115 ballistic tips. I would say start at 69 gr and work up.

Another powder is RL-33. When it first came out I tried it with 110 Accubonds. Again moly coated.

DETAILS FROM MY DOCUMENTS:

257 Weatherby 28" SS 3 groove Lilja, moly 110 accubond. Barrel now has over 750 rounds through it and throat is quite worn which can lower pressures. Just saying this rifle is most likely not the same as yours so powder charge weights will most likely require less powder. In addition a custom reamer was used which has a shorter throat and different throat angle.

Original load with moly 110 accubonds 75.5 gr of RL-25 vel 3614 fps



83 3625 which slightly faster than old load with RL-25
83.5 3674 fps shot
84 gr 3704 fps shot
84.5 gr 3735 slight signs of pressure on one case of four this is max case capacity with drop tube

I WOULD SUGGEST YOU START WITH 75 GR OF RL-33 AND WORK UP.

Very Impressive! Not that you need any more velocity or accuracy but I am curious if you have tried RL26 ? I have heard some impressive velocities, some of those from RL25 users. But, with your results I would be tempted to stop right there.

 

[cape cove]

I have also tried RL-33 in my 257 with the 117 Sierra Game King. I used 81 grs with a Fed 215 and Wea case. My velocity was 3386 ft/sec and this is with a 24" barrel. The load was somewhat compressed, great vel for a 24" tube, but accuracy wasn't that great in my rifle. I've tried this powder in my 30/378 also. I found it to be a great slow burning powder slightly faster than the old H-870 and burns very clean when the pressure get up there. My findings..