Does anyone have one? It would save a ton on brass over the Weatherby, and simple to form, and a laser for antelope.

Sorry, I was asking about the 25 300 Win Mag.

Well I've felt that it was hard to burn large amount of powder behind a 25cal. I even took the barrel off my 250PDK(250Giggs+) because I got very little gain over the basic 06.

Yes 300 mag brass will be a little cheaper. How many will you need over the life of the rifle? 3-4 boxes? How much would a set of custom dies be over the Wby dies?

Take 300 brass and form 257 Wby brass. Been done for years. You still have the option for factory ammo if needed.

If you want maximum steam, powder burn and barrel wear look at the 257STW.

Unless you just have the wildcat bug i,d just do the weatherby. You might enjoy a .257 wsm or saum. I enjoy the 25,06 and love the .257 Roberts, both can be AI ed if you want to juce it up...tj3006

I suppose you are right about how much bras is needed over the life of the bbl. This would not be an everyday shooter. What is involved with fireforming from 300 win mag to .257 wby?

I've made 257Wby from both 300 and 7mm mag brass the 7mm being a little easier. With the 300 run it in the die, trim and fire form. In my case I didn't need to thin the neck. With 7mm mag brass I ran it in the die loaded and fireformed. No trimming. The neck is a little over .06 short after forming but you won't need to trim for a long time. The Wby neck is far longer than it needs to be. I often trim new brass by .05 to put off trimming for several reloadings.

Discussed in detail:
https://forums.accuratereloading.com/eve/forums/a/tpc/f/...=593103834#593103834

The only brass my 257 Wby has ever seen is 264 Win brass (and yes 7mm Rem brass works just as good) run through the 257 size die,load and fire. Perfectly formed cases.

On the question of custom dies. Could a 300WinMag FL sizing die be used as a "body" die and a 25cal neck sizing die to do the necks?
Cheers...
Con

quote:

On the question of custom dies. Could a 300WinMag FL sizing die be used as a "body" die and a 25cal neck sizing die to do the necks?

While it is late here in Houston I don't see why not.

No you were right the first time! the 300 WSM case necked down to 25 is a hot rod. I have the reamer and my customer is getting 3800fps with 100 grainers.

quote:

Originally posted by SWD:
No you were right the first time! the 300 WSM case necked down to 25 is a hot rod. I have the reamer and my customer is getting 3800fps with 100 grainers.

PTG cut mine the same day winchester released the drawing for the 300WSM... as they probably did for 50 other people...

wicked fast, wickjed accurate, and very boring

btw, using 270wsm cases are far easier to form
jeffe

Unless you load a 257wby way down, 200pieces of brass will probably outlive any one barrel anyway.

And the 257WBY is already deep into "diminishing returns" for a .257bore.

Many would argue that the 25-06 is too much foir a 257 bore (and at that I question the 240Gibbs and the 240Wby

AllanD