Mark V's came with 24 or 26" barrels and were 28" including the accubrakes.
If it's a Weatherby factory barrel chambered in a Wby Caliber you will not be able to seat them to the lands as they will have freebore like the Remington Ultras do. A good plce to start with the Wby Mag calibers is .020" shorter than the mag box.
I load 208 Amaxes to the lands and they aren't even close to being able to eject! But with IMR 7828 (I believe 81 grains) I am getting 3050 fps and resizing is easy as could be. I even sized one without lube because I was shocked at how easy it was. Basically dropping the handle on my co-ax press punches out the primer and hardly any sizing is needed.
I suppose it is a 26", I haven't measured it. It looks like a 26" and it is my understanding that the Mark V has a 26" barrel.
Is your barrel a factory? Can you seat close to the lands? My Nosler manual lists 2972 fps from 85 gr H1000 with a 200 gr bullet so you have a fast barrel.
Woods my barrel is not factory, it is Lawton barrel (3 grove 1:10 twist). I used to seat .02 off the lads, but I have since started loading so the rounds would fit in the magazine and I forget how far off the lads I'm sitting.
Something else I've found is that the published velocities I'm seeing in manuals are always slower then my measured velocities.
In my experience the caliber of a rifle has waaaaaaaaaaay less to do with its accuracy than the quality of the rifle, the ammo and the shootist. Oh yes, you can throw a good scope into that equation too.
I have an Mk V Accumark that is completely stock except for a bedded action and a free floated barrel. I worked up a load for the 200 grain Accubond and interestingly my load is identical to Longshot's with velocity within 5 fps. It too shoots this load to half an inch regularly. I was always led to believe that the freebore Weatherby uses is there to increase the velocity rather than decrease it, because it allows higher pressures safely. Some Weatherby's a few years ago did kinda overdue the amount of freebore they used, but I think that has been corrected. A reasonable amount is not a handicap to accuracy. Enjoy your new rifle, take care of it, treat it well and it will take care of you.
I've played a bit with a number of 300 wby's. There is no reason a 26" barrel won't easily do 3200 with a 180 grainer.
If you have wby freebore you should be able to work up to 83/84 re22 and 84/85 of 7828 with 180's.
My reg mark V loves 85 of I7828 under most any 180.
My ultralight was extremely fussy but now loves 88 grains retumbo under a 180 tsx. Went from a pie plate grouper at 300 yds to 2"/300yds.
I purchased a .300 Weatherby back in the 80's, a LazerMark 26" Mark V. Love the rifle. Shoots 1/2" with factory or my handloads. Mine was made in Japan. I load using Norma MRP, Federal 215 primer, and 150, and 180 grain Hornady SP's flat base bullets for most shooting but do have a load for 165 btsp also. I get approx. 3450fps with the 150's using a max load of Norma MRP powder. I also get good results with IMR 4831.
Negatives: kicks like a mule but i don't mind. Not fun working up loads off a bench as you'll come home with a sore shoulder. Brass is outrageously priced. Belted magnum cases require special attention when reloading or you will only get 4-5 loadings per case. When sizing you HAVE to size and not push the shoulder of the case back to minimum or you will get case stretching just in front of the belt and possible separation. You need a gage to measure the amount of shoulder setback when sizing.
I recommend a synthetic stock for a hunting rifle because if it gets wet wood can warp. I broke the pistol grip off my LazerMark stock and sent it back to Weatherby and they replaced the wood with the FiberMark stock that I requested. My fault that I broke the stock pistol grip and not a defect. Requires a good scope and rings to handle the recoil. One piece bases are stronger.
I had to have a Weatherby too, but now I shoot mostly smaller calibers.
My dad is shooting a Vanguard in 300 wby and he has shot it for years with OK accuracy but nothing spectacular but this past year we got into long range shooting and he pulled it out and put some 210 Bergers in it and it shot OK then he pushed them in till he could cycle through the mag. and then shot the best group it has ever shot, five shots just under 3/4 in. He's trying some Hodgdon Hybrid powder and getting 2950's with out pushing it hard. He wants to change the stock out to something better fitted for long range but other than that it is a keeper.
I've seen a lot of good info on this site for getting them to shoot, In my mind the belted case not being accurate has been debunked by some on the site. Different yes but do what the cartridge likes and get good results they all like something a little different.
Last edited by bigngreen; 03-29-2009 at 10:27 AM.
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