matching the performance of factory weatherby ammo

[alaska]

I could get real close with 165gr loads in my old 300 WBY but never could match the 180gr load.

With IMR 4350 and H4831 the two best powders I used over the years in my 300 WBY.

Now I still use H4831 with Speer 200gr at 3000 FPS in 26" as my standard load.

Even using Norma MRP Powder...........

 

[skeeterboud]

You guys are great! thanks for all of the help. the 257 is a 24" bbl semi/customed v/g that shoots amazing. i really like the performance of the 100gr factory spire point factory, and would like to duplicate it. these texas deer don't stand a chance against it. mine chrono's 3445 fps avg. all i want is to match the performance/accuracy.

does anyone have any loads for a mark v accumark 270 weatherby mag that duplicate the factory 150 sp load? i do have 140 accubonds and partitions in that caliber, as well.

 

[sox35]

I use h1000 with Berger 115vld's. In my experience it performs best with the heavier bullets in the .257 WBY. I don't have any info on the 110's but would expect it to perform exceptional.

On the Factory loads, Weatherby does not load it's own ammo. It is outsourced to more than one source. My buddy that worked at Hornady said they would use a blend of powders but was not allowed to say what they exactly were or amounts. Only thing he would say is it is nothing I can get. I do know they used Weatherby brass made by Norma and Weatherby would send them rifles for the testing. I sure wish he still worked there, I used to have a stockpile big enough to take on a small country.

 

[alaska]

Norma has been Weatherbys loader for many years

I beleve it even says on the box made in sweden

What a sweet round the 257 Wby

Mine is a Accumark and loves the 100gr Barnes TTSX with IMR 4831.

 

[cummin_un_glued]

I use h1000 with Berger 115vld's. In my experience it performs best with the heavier bullets in the .257 WBY. I don't have any info on the 110's but would expect it to perform exceptional.

On the Factory loads, Weatherby does not load it's own ammo. It is outsourced to more than one source. My buddy that worked at Hornady said they would use a blend of powders but was not allowed to say what they exactly were or amounts. Only thing he would say is it is nothing I can get. I do know they used Weatherby brass made by Norma and Weatherby would send them rifles for the testing. I sure wish he still worked there, I used to have a stockpile big enough to take on a small country.

just for reference because i plan to load the 115 bergers also, how much h1000 are you using with them?

 

[sox35]

I settled on 68g of H1000 with the bergers, 3240fps. I have taken big whitetails out to 434 yards with great results. A 230 pound 10 pointer took its last breath at 12 yards last year, no exit wound but very little meat damage. It looked like a grenade exploded inside the chest. Bergers load data max load is 69.1g for H1000 at 3277fps.

 

[cummin_un_glued]

I settled on 68g of H1000 with the bergers, 3240fps. I have taken big whitetails out to 434 yards with great results. A 230 pound 10 pointer took its last breath at 12 yards last year, no exit wound but very little meat damage. It looked like a grenade exploded inside the chest. Bergers load data max load is 69.1g for H1000 at 3277fps.

cool thanks for the info

 

[lloydsmale]

I know back in the day weatherby loaded with norma mpr which is nothing but re22. My guess is they load a bit hotter then the conservitive loading manuals.