How Much Freebore? - Wby 257 Mag.

[Ackman]

Oh hell no!

FIRST ORDER OF BUSINESS-FORGET FACTORY AMMO

zero to .030 freebore is the way to go, and forget ever shooting factory ammo, they would not chamber in the rifle anyway.

I have worked up loads for more than a few.

26" barrel-10twist-accuracy nodes as follows
100g at 3850
115 at 3600

26"-9T
110g accoubond and 115g berger vld hunting
3550 fps

30" 10 twist
100g at 4000,

tiny groups abound...TINY!!!

with a good muzzle break on the rifle, you see the deer drop as the gun recoils....sweet!

Typical rifle with zero to .030 freebore takes 12-19 rounds of load development per bullet type...dumb butt simple to say the least.

After you have worked up loads for half a dozen of these with short freebore, you are hooked for life. Shorter freebore also gives you 2x the barrel life over a standard chamber.

.400 freebore chambers does keep gunsmiths spinning on new barrels every 600 rounds!

Mine has a long 12 twist barrel with that same reamer, NO freebore....100gr. Sierras @4000, sweet spot is at 1/4" accuracy. What's not to like. I can't even imagine chambering one of these things with .500 freebore,, or why anyone would even consider it.

 

[284winner]

I'm not a big Weatherby afficianado but I do own a couple. Both have long freebore chambers. 7 Mag and 300 Mag. Plenty long enough for the longest match bullet made for those calibers. One thing they both do is shoot very good with most bullets except Berger's. The heaviest Berger's do shoot ok in them but lighter bullets for caliber do not shoot well at all. I suspect it's due to the excessive jump. Hornady match bullets shoot the best in these two rifles.

 

[Matches]

To the original poster.
If and only if your a reloader and don't plan on using factory ammunition.
Pick the bullet you plan on shooting and seat it into a case so that the boat tail to bearing surface junction is 0.050 above the neck/shoulder junction.
This will allow you to seat the bullets off of the lands without putting the boat tail junction of the bullet into the donut at the neck/shoulder junction.
If your shooting copper or brass bullets only use 0.100 so you have more room for seating deeper.
If all of this sounds strange take Stan's advice as he makes barrels and has been at this longer than most.

 

[Ironworker]

I pondered that question for a while. I decided to have it chambered with factory free bore . 10"twist Bartlein bbl 1/2-3/4 MOA frequent group size . 74grs of Re#26 pushes a 90gr Sierra 3900 FPS .

 

[AckleymanII]

I would NOT agree with your choice....bad idea.

I have two now, 9T, 26" .030 freebore

100's at 3850

115 at 3600

Tiny, tiny groups with little load development with each bullet weight, less than 20 rounds on each bullet.

Factory freebore = short barrel life

Best of luck to you!