257 wby and H1000

[cummin_un_glued]

so i'm working up loads for my 257 with 110gr accubonds. started at 71gr to 75gr in .5 gr steps. 73gr show's great promise with a vertical seperation of only .5" at 200y. my question tho is i seem to have only found one node in this powder range. i dont have a book that shows this powder for a 257 but it does show a 7mm mag with a 120gr to be min 70gr and max of 77gr+ so should i keep going up from 75gr and see if there is another node on up there?

 

[mrultramag]

Nosler shows a max of 74 gr H1000 over 110 AB for 3446 fps using a 26" lilja bbl and fed 215 Primer. What kind of fps are you getting? What is your bbl length? I would say that if you are getting 3450 or so you are pretty much toward max. I found that even using RL25 I was getting toward max at the same types of velocity- 3450 or so. You might try IMR 7828, for some reason it produces good velocity in the 257. But I'll bet that you have a good load there with H1000 if your 1/2 moa at 200 yd.

 

[cummin_un_glued]

thanks for the reply. yes the 73gr load shoots very nice indeed. i do not have a chrono but with a 200y zero they are dropping 3 moa at 370 yards. yes i know its an odd yardage but thats where i was shooting from. i did try 76 today and that is too much for sure wont be trying that again. its a 24" factory barrel.

 

[frequent misser]

You are real close to max with that load. According to your drops you are just a tad over 3400. I got a little better velocity with retumbo rather than h1000 in mine. 7828 didn't produce the velocities in my rifle. At over 3400 you aren't going to get much gain by switching powder. If you have an accurate load I would stick with it.

 

[Trickymissfit]

so i'm working up loads for my 257 with 110gr accubonds. started at 71gr to 75gr in .5 gr steps. 73gr show's great promise with a vertical seperation of only .5" at 200y. my question tho is i seem to have only found one node in this powder range. i dont have a book that shows this powder for a 257 but it does show a 7mm mag with a 120gr to be min 70gr and max of 77gr+ so should i keep going up from 75gr and see if there is another node on up there?

A BIG THANKYOU!!!

The 270mag case and the .257 case are similar, and I just never thought much about H1000!! Looked it up in the Hogdon manual, and I gotta give it a try.
gary

 

[cummin_un_glued]

Talking about similar cases and why i used 7mm rem mag data. I read over on another forum about using 7mm rem mag brass resized down to 257 wby. I gave that a go the other night and it worked just fine. After light trimming the only difference i noticed besides the head stamp is that tge neck is 050" shorter using the 7mm brass. I just shot some of them yesterday to finish forming them. I will try to post some step by steps later this evening for those interested. I will probably put it in its own thred.

 

[Trickymissfit]

Talking about similar cases and why i used 7mm rem mag data. I read over on another forum about using 7mm rem mag brass resized down to 257 wby. I gave that a go the other night and it worked just fine. After light trimming the only difference i noticed besides the head stamp is that tge neck is 050" shorter using the 7mm brass. I just shot some of them yesterday to finish forming them. I will try to post some step by steps later this evening for those interested. I will probably put it in its own thred.

I thought about necking up the 270 mag brass to .308 once. I figure that the 7mm mag will push a 160 grain bullet to 3100fps without too much trouble, then the 30 caliber ought to be at least as fast with the 168 grain bullet. But then discovered that a .308 Norma is virtually the samething! Oh well! But one could form cases out of 300 Win mag brass, and move the shoulder out about .06" and get a longer neck at the sametime with something like a 30 degree shoulder angle. It would be a far better round than the .300 mag with similar velocities untill you got over 200 grains when it would take over with the longer neck keeping the base of the bullets out of the shoulder. But of course somebody somewhere has already done it a couple times over
gary

 

[cummin_un_glued]

what i'm talking about isnt making a new round just a way to source brass for less money.

 

[Trickymissfit]

what i'm talking about isnt making a new round just a way to source brass for less money.

I realize that. I would seat my bullets out as far as I safely could to help make up for the .05" short case length. The Weatherby cases don't seem to grow a lot (in my case anyway), so I suspect they'll always come in short. Somebody needs to market a good 145 grain 25 caliber bullet suited for the velocities that can be obtained from the .257mag.
gary

 

[mhiltz]

I use 264 Win mag brass for my 257 Weatherby. The only problem is, fire forming the cases sure wears out the barrel faster. It would be nice to have two rifles, one to fire form with, and the other to do the hunting, or target shooting only. It may be worth it in the long run to just buy the expensive Weatherby brass.

I like the idea of the 145gr 25 caliber bullet for the Weatherby too.gun)

The H1000 is the powder that I use with the 110gr Accubond @ 72.0 grains. It shoots very good there for me. Chrony'd them right at 3400 fps. My group at 100yds is .777" which works for me.

 

[cummin_un_glued]

higher bc 25 cal bullets would be great

 

[lloydsmale]

id say the load you allready have will take care of anything your going to do with a 257. Why fix something that isnt broke?

 

[Trickymissfit]

id say the load you allready have will take care of anything your going to do with a 257. Why fix something that isnt broke?

because the .257 mag is capable of driving a 150 grain bullet without a whimper, and the heavier bullet makes better use of the large case capacity
gary

 

[cummin_un_glued]

i did test my load more yesterday and i am very pleased with it.

a 25cal 150gr bullet could be close to the same bc as a 180gr 284 bullet i think?