I am considering the rebarrel of a LH Remington 7mm Remington Magnum into a .257 Weatherby. Some loading data shows a barrel length of 24" and others 26", I am looking for input on the velocities the round is capable of with each. I've even thought about going longer than 26" as this gun isn't going to be something I tote through the woods. I'll probably be shooting 100g Barnes TTSX bullets from it and would be tickled if I could get 3600+ fps.

Also - assuming I allow the barrel to cool properly, what is the approx barrel life of this round with a quality tube?

Buzz,

The last 257 Wby I had started @ 26" and ended @ 23", it lost a bit over 90 fps total with the 3" cut.

7828 is a good powder as is R22 and I hear good things about Magnum.

AS for round count, for the bestest of accuracy and good clean up you'll be in the 1700-2500 rounds for the most part.

Dober

Personally i would go with a 26 inch tube but in reality and the world of hunting a 24 would work fine.

I have 24" barrel on a Mark 5 weatherby

I do 3600 from a 24" tube.

Also have no idea how long the tube will last if you allow it to cool properly, but that's any cartridge cuzz I don't know how to let something cool.

buzz-- go ahead and do it!

That's what I told him too. But as you know, he'll have to dwell in a 4th dimension thought process about it for 3 months, calculate the theoretical assessments surrounding the statistical probability of how it would formulate into his grand scheme of rifle and cartridge usability.

Oh - I think it's going to happen, I just have to work out a few more details. I want to keep my current McMillan stock which is inletted for a Remington Magnum sporter, so I need to figure out what contours will work with this stock, etc.

For my next .257 rebarrel project, I'm going with-

25"

he could design some software that would help him decide....

Tough crowd... Hey - when you plunk down a bunch of money on a custom you want it to be just right. I am still working out my details on the contour, length, and choice of scope.

Steelhead - what do you scope yours with? A 6x Loopie with turrents?

How about a Remington Magnum sporter?

I'm sure his Dot Net program will come to that conclusion as soon as some processing power is freed up...

Certainly thinking about it My buddies are giving me crap, but I am a goober when it comes to this stuff. I need to figure out how much this sucker is going to weigh in this chambering with several contours and go from there. I'm not looking for a LW gun, but I don't want a 10.5# club either

That contour for the non-African bores isn't too much.

I'll do some measurements on the factory tube and compare it to the Krieger contours. On their website they list the smallest contour they make in SS for a .257 bore is a #4. I do want to go stainless on this one. It would be nice if they'd do the Remington contour in SS.

3.5-10x with Turrets, can't like Turrents except for shooting in Oregon....

Buzz,
Lilja has a barrel contour weight calculator on his web site that you can play with and come up with a weight. May help you to decide what you want.

Dave

Try Pacnor...

I've a SS Win 70 Classic with a 25" #3 Lilja stocked in a McMillan Classic, blind mag, 4.5-14x40 in Leupold DD it's 9# on the dot with 3 in the belly and a sling. It'll run 100gn TSX's and SGK's to 3650fps with Ramshot Magnum.

To do over again I mandate a shorter full-length shank, mine is 2" forward of the action, 1" would have been plenty, and I had the stock on hand, if I was ordering I'd have done an edge and probably Talley's and with those changes I beleive it'd be just under 8#.

If you want to see some exceptional accuracy do away with all that freebore and you will get an additional 200+ fps: find a gunsmith or Use Pac Nor barrel and let them do the chamber.

I had two with zero freebore and the 100's shot groups in the low 3's at 3800 fps with the 100's. Pac Nor 3 grooves are what I had and they are sure accurate and fast.

Not for free.

Nope. The extra velocity comes because of extra pressure.

I used to think getting rid of the freebore would help accuracy too. Then I acquired a couple of Weatherby rifles (yes, plain old factory Vanguards in .257 and .300) that will shoot 1/2 MOA as far out as I want to shoot at big game. So hello freebore....

Thanks for the input folks. I'll be getting the ball rolling on this project soon.

My NULA .257 ROY has tons of freebore..will run out of magazine long before it gets near the rifling...pretty much shoots most anything into 1/2"

BTW 25" barrel on that one.

LC

So long as everything is 'cut' straight, jump don't hurt anything.

I'm running a 24" tube on my Vanguard, getting 3550 with 7828 and a 100TSX.

Accuracy is outstanding...

Tony

My Mk V had a 26 inch bbl, my two custom 257 WBYs had, and have 27.5 inch barrels. Shilen on the one I sold 15 years ago and Pac Nor on my current 25ROY. Both would hit 3800 FPS pretty easily with Moly'ed 100gr bullets. I am using only the Barnes TSX's right now and when they are all shot up I will try the tipped version. Quite the lights out round for deer and similar sized stuff. If you are not going to pack the rifle around too much, no reason not to go with the longer barrel lenghts. I pack mine around quite a lot and I STILL don't mind the 27.5 inch barrel or 10lb weight.

I have not noticed any lack of accuracy from having normal freebore. All have shot better than I am capable of utilizing.

here's a plain ole cheap vanguard.
73.5 grains of reloader 22 under a barnes 100 grain tsx.

lower hole is from a clean cold bore, then the next 2, about a 1/2 group !

I wish you guys would quit this. It's been tough trying to keep from buying or building another rifle and slip it in the house/safe undetected.
The Weatherby guys say this was Roy's favorite (and that's enough reason to have one) and then a guy looks at the ballistics and wow.
Anyone want a 25" Magnum contour, fluted, and lapped Spencer barrel in 7MM RM for a 75 Sako?? Less than 50 rounds thru it. $250.00 free shipping. Guess what gets put back on it.

Merry Christmas!!
Dave

Racetire, I shoot the barnes 120g Tripple shocks in my 7 mag at 3600 fps with Rem brass, CCI 250, and 72.0g of R#22, bullets all touch at 100 yds.

Sounds like you have all you need! The 257 will only equal the 7 Mag with this load with the 120's IF it can equal it at all!

Your Spencer barrel should be one heck of a shooter!