rebarreling a weatherby mark V

[Prieto9000]

I have a 300 way mag mark V that needs to be rebarreled. Groups are awful, the all fall in the 5"-6" range @ 100yds. I noticed the stock was broken so I decided to buy a B&C for it but the problem persisted. The next thing is to rebarrel but can´t decide on the caliber. I really like the action and the stock is pretty decent so I´d like to make a nice hunting rig. I was thinking about a 28 Nosler, but I already own one so.... Any thoughts?? 28 Nosler, 300 RUM, 6.5 SS, anything else??

 

[MudRunner2005]

Why not mix it up and build you a 7mm STW... Or a .300 Ackley Improved Magnum (which uses .300 Wby brass to form for it).

 

[sable tireur]

Groups are awful, the all fall in the 5"-6" range @ 100yds.

Do you reload or do you shoot only factory ammunition?

When we see groups this large, there is generally something very wrong. I would have thought that a broken stock would be the biggest failure I could imagine but if the groups remain consistently large then there is obviously something else amiss. Have you checked the scope, scope mounts and rings? Is the barreled action tightened into the stock properly? Is something touching in the barrel channel? Maybe a visit to the gunsmith might be in order for a diagnostic look see.

I don't disagree that a re-barrel might be the best solution, especially given the Weatherby factory chamber design. But I would also suggest considering a good bedding job be included after the re-barrel.

As to cartridge selection, the obvious choice would be the .300 Weatherby. I don't think you want to duplicate the 28 Nosler so the bigger 7mm selections can be discarded. Which way do you want to go?

Smaller could include the 26 Nosler or the .264 Win. Mag. especially if you reload. Weatherby released the 6.5-300 Weatherby Mag. also.

If you want to try something bigger you might consider the .338 Win. Mag. or the .340 Weatherby Mag.

Classic cartridges would include the .300 H&H mag. or the .375 H&H Mag. both of which can be loaded for higher or lower energy requirements. The .375 H&H can be loaded with the 260 grain Accubond for an exceptional Elk cartridge. A modern rendition would be the .375 Ruger.

Enjoy the process!

 

[J E Custom]

I have a 300 way mag mark V that needs to be rebarreled. Groups are awful, the all fall in the 5"-6" range @ 100yds. I noticed the stock was broken so I decided to buy a B&C for it but the problem persisted. The next thing is to rebarrel but can´t decide on the caliber. I really like the action and the stock is pretty decent so I´d like to make a nice hunting rig. I was thinking about a 28 Nosler, but I already own one so.... Any thoughts?? 28 Nosler, 300 RUM, 6.5 SS, anything else??

I would recommend staying with the 300 Weatherby mag because it is a great cartridge and you probably already have lots of brass for it. It would also be the easiest re barrel, In that no mods would have to be made to the action.

If you re barrel, go with a magnum contour (Like a #5 contour) and accuracy will be good.

The 300 Weatherby will do almost everything well, And if you reload, even better.

J E CUSTOM

 

[Dr. Vette]

When I've had this happen, the scope is #1 on my list of likely culprits.
However, I'd also wonder if you have tried more than 1 type of ammo. That too can make a big difference.
Or, if you're like some, flinching from the recoil.

 

[Dosh]

9000, perhaps before going to the expense of a rebarrel, have the barrel borescoped. This will tell you if the rebarrel is justified. I have a .270Wby Mark V with a barrel that's toast, verified by borescoping it. If your barrel is ok, follow previous suggestions.

 

[Prieto9000]

Do you reload or do you shoot only factory ammunition?

When we see groups this large, there is generally something very wrong. I would have thought that a broken stock would be the biggest failure I could imagine but if the groups remain consistently large then there is obviously something else amiss. Have you checked the scope, scope mounts and rings? Is the barreled action tightened into the stock properly? Is something touching in the barrel channel? Maybe a visit to the gunsmith might be in order for a diagnostic look see.

I don't disagree that a re-barrel might be the best solution, especially given the Weatherby factory chamber design. But I would also suggest considering a good bedding job be included after the re-barrel.

As to cartridge selection, the obvious choice would be the .300 Weatherby. I don't think you want to duplicate the 28 Nosler so the bigger 7mm selections can be discarded. Which way do you want to go?

Smaller could include the 26 Nosler or the .264 Win. Mag. especially if you reload. Weatherby released the 6.5-300 Weatherby Mag. also.

If you want to try something bigger you might consider the .338 Win. Mag. or the .340 Weatherby Mag.

Classic cartridges would include the .300 H&H mag. or the .375 H&H Mag. both of which can be loaded for higher or lower energy requirements. The .375 H&H can be loaded with the 260 grain Accubond for an exceptional Elk cartridge. A modern rendition would be the .375 Ruger.

Enjoy the process!

I´ve tried everything ammowise. I started with the 180gr weatherby bear claw. I have like 100 rounds of it. When that didn't worked I tried the hornady 180 interlock ammo with very similar results. Then I moved to hand loaded ammo using 190 bergers, 180 Accubond, 168 Nosler BT, 208 hornady ELD and nothing changed.

Regarding the stock, I used deacon 10110 to bed the action to the stock and I torque all my stocks to 55 in Lb using my FAT wrench.

I would recommend staying with the 300 Weatherby mag because it is a great cartridge and you probably already have lots of brass for it. It would also be the easiest re barrel, In that no mods would have to be made to the action.

If you re barrel, go with a magnum contour (Like a #5 contour) and accuracy will be good.

The 300 Weatherby will do almost everything well, And if you reload, even better.

J E CUSTOM

I´m considering a bartlein 3b fluted or a #5 fluted Benchmark.
I don´t really like the 300 wby. If I stick with a .30 maybe it would be a 300 RUM. There´s something about wby calibers that bother me. The only reason I got this rifle was because it was too cheap to refuse.

When I've had this happen, the scope is #1 on my list of likely culprits.
However, I'd also wonder if you have tried more than 1 type of ammo. That too can make a big difference.
Or, if you're like some, flinching from the recoil.

Tried different scopes, bases and rings. It all came down to a faulty barrel.

 

[Deleted member 46119]

The only reason I got this rifle was because it was too cheap to refuse.

Well you got one of the strongest actions around. If it was cheap but worth it for the action you are ahead.

Now my opinion/suggestion

It's a Mark V do a "big" magnum.

The Mark V action is perfect for RUM or XX-Nosler, any of them. No other work required just change the barrel.

Which RUM? (licks finger and sticks it into the wind) 300 of course. Oh wait, I really like 338s. Hmmm...

Which Nosler depends on your preferences. 26,27,28,30 or 33. If you are going to hunt bigger stuff, Elk, Moose, Brown bear IIWM I'd lean toward the 33 or of course my preference a 338/28-Nosler. For general purposes the 30 will meet or exceed the 300Wby again my preference is a 308/28-Nosler. If you are not going for Moose or Brown Bear. The 28 will do everything you could desire with authority as far as you can spot the game. If you want to go fast for Speed Goats the 27 or 277/26-Nosler can launch the typical 130s at 3400fps+ as there is less restriction than the 26 so less pressure at higher speeds. I'm pretty sure I got Matrix 165s up to 3100+ but it was not a Mark V action and that was pushing it. An 8twist 277 barrek and Berger 170s? Hm.

While the 338/28-Nosler doesn't have the legs of the 338 Edge or 338 Lapua, with bullets 250grains and below it is very respectable. My favorite bullets for the 338/28-Nosler are Barnes 210 TTSX and 185 TTSX. Every elk I hit (2) with the 185 leaving the muzzle at nearly 3300fps was DRT, even if it wasn't a perfect shot. The shock to the system put them down.

 

[sable tireur]

I´ve tried everything ammowise. I started with the 180gr weatherby bear claw. I have like 100 rounds of it. When that didn't worked I tried the hornady 180 interlock ammo with very similar results. Then I moved to hand loaded ammo using 190 bergers, 180 Accubond, 168 Nosler BT, 208 hornady ELD and nothing changed.

Regarding the stock, I used deacon 10110 to bed the action to the stock and I torque all my stocks to 55 in Lb using my FAT wrench.

Thank you for posting this information as it really gets us up to speed with your process of elimination, which is excellent by the way!

I´m considering a bartlein 3b fluted or a #5 fluted Benchmark.
I don´t really like the 300 wby.

I've used hundreds of Bartlein barrels and I have never been disappointed. The #3b contour is an excellent choice for your project without making the rifle too heavy to be comfortable to carry all day.

I'm glad you pointed out your dislike for the Weatherby cartridges since that eliminates those from the range of choice. The RUM may be the choice given your parameters, although brass quality may be a drawback since only Norma, Hornady and Nosler are creating stock right now. The Remington brass has always performed better for me in my 300/338/375 RUM rifles. All three are pricey.

Regards.

ADDED:
7mm RUM with Bartlein #3b barrel:

Enjoy!

 

[coop2564]

Are you sure it needs re-barreled many a gun gets so copper fouled they shoot like that. I've had to clean some guns every morning and night for a week letting them soak in-between cleanings to get all the copper out of them.

 

[sable tireur]

I've had to clean some guns every morning and night for a week letting them soak in-between cleanings to get all the copper out of them.

No offense but...

If I found myself with a barrel such as you describe, I would have torn it off and thrown it away. Using it for a tomato stake would have been too good for it! Those barrels are a waste of time, effort and materials, being poorly made in the first place. There is no justification to cleaning a barrel that intensively for that long when significantly better barrels are available. Think of all the time and money you could have saved by using a Bartlein, Krieger, Brux, or any of the other better barrels.

Regards.

 

[coop2564]

No offense but...

If I found myself with a barrel such as you describe, I would have torn it off and thrown it away. Using it for a tomato stake would have been too good for it! Those barrels are a waste of time, effort and materials, being poorly made in the first place. There is no justification to cleaning a barrel that intensively for that long when significantly better barrels are available. Think of all the time and money you could have saved by using a Bartlein, Krieger, Brux, or any of the other better barrels.

Regards.

It was bought 2nd hand and never cleaned properly. I dont let my guns get to this point.
My point was copper is very hard to remove and will make a gun shoot just like the OP is describing.

 

[Hornhunter32]

300 or 338 Norma. You'll have to open up the bolt face, but it's not a big deal. I currently have a 300 Norma Improved built on a Wby action, and when the barrel is toast, I'm going to try the 338.

 

[jrsolocam]

Ive had 3 Mark V's rechambered to 22-250 (8tw), 300 RUM and 300 Dakota. No trouble and they shoot great. The 300 Dakota had to have the bolt face opened up a hair. 4" box for the big Bergers, whats not to like??