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Weatherby Mk5 Ultralight - fluted barrel question

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05 March 2015, 13:23
kiwiwildcat
Weatherby Mk5 Ultralight - fluted barrel question
Hey guys,

Firstly, can someone tell me what contour their fluted barrels are?

Secondly, for anyone who has one of these barrels, how do they shoot and are they good for grouping with 5 rounds, or does the group open up after 3 shots

The reason I ask this is, for a lightweight mountain rifle build, what would be the recommended contour to use for a fluted barrel. I have had Remington Mountain rifles in the past and don't want a skinny barrel like those, likewise a Kimber I once owned in 7mm WSM was also a bit skinny in the end and best groups were between 1.5 - 2 inches at 100 yards.


She was only the Fish Mongers daughter. But she lay on the slab and said 'fillet'
11 March 2015, 04:10
kiwiwildcat
Decided to go for a number 3 contour and fluted.


She was only the Fish Mongers daughter. But she lay on the slab and said 'fillet'
11 March 2015, 15:50
eezridr
I have a Mark V 270 WM. The rifle is finicky but capable of very good accuracy.
Great for carrying like you suggest but like any light weight rifle, I is difficult to hold still for very long shots.
Sort of a oxymoron.
14 March 2015, 23:19
POP
My 270 Ultralight!








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26 April 2015, 03:42
Art S.
I just bought a 240 WM in the Ultra Lightweight. I had wanted one for years, but they have been out of stock for a couple of years. They must have made a batch, since they started appearing, so I ordered one. The only thing I did was replace the trigger with an aftermarket that would go down to 1.5 pounds.

The barrel is about .55 at the muzzle, it appears, and is fluted for half it's length. The gun is advertised at 5 3/4 pounds, but it is over by 4 oz. The same is true of a Savage LWT model 11 in 6.5 Creedmoor which I just picked up. It is advertised at 5.5 pounds, but is also 4 oz over. Gun weight specs are based on the largest caliber available generally, since they weigh the least. The smallest calibers are always the heaviest, since there is more steel left in the barrel.

The 240 barrel is not floated, so I expected it to heat up. I took it to the range and fired 4 shots at 25 yds to roughly sight it in. I then let it cool for 10 minutes. It was about 60 deg out. At 100 yds, I then fired, with about 15 seconds between shots, a three shot group of factory 100 gr spire pt, a 3 shot group of full bore 95 gr Partitions and a 5 shot group of 85 gr TTSX full bore loads. I was going to shoot slow groups, but through the spotting scope I could see that accuracy was holding pretty well.

I hate to even give the results, but they are true. I shoot quite a bit with accurate rifles, and am pretty good at group shooting. The 100 soft points went into .31 inches, the Partitions into .51 and the first three of the TTSX shots went into .34. The fourth and fifth TTSX went down about 2 then 4 inches. It looks like the accuracy lasted about 8-9 full bore loads before heat reared its head. After the 11th shot, the barrel would burn bare fingers and took about 20 minutes to cool down.

This gun weighs exactly 7 pounds with the gun, a set of light scope rings and bases and a 12 oz Swarovski Z3 10X variable. I think weatherby makes much better barrels than they used to. I bought a 240 Vanguard S2 a couple of months ago and with a Nightforce varmint scope, it also shoots into around .35 inches. It weighs, however, over 10 pounds with the larger scope.

The savage LWT Creedmoor, which is a specialty line and not very cheap, also shot well. It shot the 120 Amax and 129 TSX loads into .71 and .54 inches inches. This with a rifle that all up is exactly 6 1/2 pounds (Leupold VX2 3-9 Ultralight).

I think the answer is that a really tiny barrel can shoot really well if the barrel quality is high, you have a good light trigger and you can control such a light rifle. You just can't pound out a lot of rounds in a session and they are really hard to shoot offhand.
26 April 2015, 03:47
Art S.
Forgot to mention that the Ultra Lightweight barrels in the non Weatherby calibers have only 7/8 " barrel shanks. I bought a new pull off in 338/06 once, and adapted it to a Mauser. The thread was 7/8 x 18. I think this is because the 6 lug MkV is simply a lengthened Varmintmaster action (22-250 head) which always had that thread size.
26 April 2015, 23:51
farbedo
I did the same with one of those 338/06 barrels, but stubbed it for a Savage 110. Kind of an interesting project, and made a nice rifle.

Jeremy
20 June 2015, 17:58
Dogleg
I had one in .300 Weatherby and it never did shoot very well. About the only thing that it really had going for it was it always put the cold shot in the same place. I rebarrelled it with a #2 Gaillard in .300 Win which is about the same as a Remington magnum contour. That cured it, but its not so light anymore.

I find myself in the odd situation of liking Mark Vs, while still not being very impressed by them. I still have 3, but doubt if I'll ever buy another.