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New barrel for Mk. V in 7mm Wby. Mag. - length and contour?

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29 June 2012, 14:04
McStern
New barrel for Mk. V in 7mm Wby. Mag. - length and contour?
Hi all,

the blooming rifle just will not shoot straight.
Therefore: a new barrel is required, BUT which length, twist rate and contour?

intended use of rifle:

- red deer / fallow deer
- <300 m
- >160 grain (copper) bullets
- "mountains", e.g. Scottish Highlands, the Alps --> portability desired!
- max. 2 shots in a row (hopefully Wink )

Looking forward to your advice

cheers
29 June 2012, 17:36
snowman
I have a Wby MkV in 7mm Wby that will not shoot heavy bullets. It seems to have a 1 in 12" twist. It will however shoot 140 Barnes TSX bullets into tiny little groups. so thats what I shoot in that rifle. At one time I had considered changing the barrel and I was thinking about staying with the factory contour, stay with 26 in length and go to a 1 in 9" twist.
29 June 2012, 17:44
IOWADON
I bought a 7mm Wby Mark V in 1964 when in high school and had it re-barreled three times. Each time was a relatively big expense. However, I think Weatherby has a very reasonable price for re-barreling their rifles, and I think the twist rate is now 1-in-10 inches whereas in 1964 it was 1-in-12 inches.
29 June 2012, 18:26
Jim Kobe
My opinion, the barrel ain't the problem; it is the chamber. Wby chambers all have Verrrry long throats. Have it rebarreld with a good 10" twist barrel and chamber with a no-throat reamer and custom throat it for your desired bullet.


Jim Kobe
10841 Oxborough Ave So
Bloomington MN 55437
952.884.6031
Former Professional member American Custom Gunmakers Guild

29 June 2012, 18:27
farbedo
24" if you aren't looking for top velocity. 26" if you are. Standard sporter weight contour. I like a #3 Shilen, or #1300 Lothar Walther.

I wouldn't go slower than 1 in 9" for the twist. A 160gr bullets isn't really long, but in all copper it could use a little faster twist. IMHO.

Jeremy
30 June 2012, 00:22
McStern
Thanks for the advice. Sounds like there is an inherent problem with the Wby. due to the throats. would it, in your opinion be more sensible to rebarrel for a .300 Win Mag? More factory ammo, less problems with precision?

thanks again for the advice!
30 June 2012, 05:01
DArcy_Echols_Co
There is a potential problem with non factory or short throat 7 mm Wtby made outside of Germany. It will be submitted to pass proof when it is imported. I could be wrong perhaps Jaeger-Frank will lend some comment here. We build quite a few Legends chambered for 300 Wtby with short throats and they shoot very well. You can use MOST Factory ammo if you hand-loads go to Paris while you land in Arusha. As a rule they are a bit specialized. I am not sure I would recommend a radical non-standard throat and lead angel for a rifle headed to the proof house in Germany.

1-10 twist, with a cylindrical shaped throat and an OD no larger than .285. Use a 1-1/2 degree lead angle per side and the approximate Weatherby free-bore length will likely shoot pretty well for a sporter.

But thats just one mans opinion
30 June 2012, 09:29
<Mike McGuire>
The key is the freebore diameter needs to be very close to bullet diameter.

378s and 460s have a full 3/4" from case mouthto rifling. From the custon shop a bullet will not drop down the free bore section.