29 June 2012, 14:04
McSternNew 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

)
Looking forward to your advice
cheers
29 June 2012, 17:36
snowmanI 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
IOWADONI 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 KobeMy 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.
29 June 2012, 18:27
farbedo24" 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
McSternThanks 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_CoThere 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.