300 Weatherby...

zigliss

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Nov 12, 2008
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Northamptonshire, UK
Ok Chaps - it looks like I am about to cave into my 20 year old 300 Weatherby Mag fantasy and make the purchase....

As always with relatively esoteric calibres (well in these parts anyway) there seems to be a wide range of views (often based on no real knowledge). Couple of the negatives folks have thrown at me are as follows:

- Very inaccurate.....
- Inefficient cartridge with regards to powder required for velocity...

Just wanted to get the thoughts/comments of anyone with actual experience of the calibre can help either confirm or dispel these myths/facts and perhaps provide some reloading data around what works for you?

Many thanks...

BTW - it will be used for deer and some range work.....
 
This one should be "interesting"..........

I have owned several Winchester and Remington rifles (and seen several others) in .300 Weatherby. Presently have one .300 Weatherby/Rem. 700 with factory (custom shop?) fiberglass/kevlar stock, the others have moved on to other owners.

The only reason I still have this one is that I want to use the action and stock for something that will shoot better than the 1.5 inch/100 yard groups that I have been able to get with it so far.

Now, my Remington and Winchester rifles in .300 Win. Mag and .300 Rem Ultra always shoot less than MOA if I hold properly.

I was able to acquire two Win. 70s in .300 Ultra before the Conn. factory turned out the lights---wanted to use the actions for "something" but decided to shoot one of them just for grins.
I bedded the tupperware stock with Steelbed just to be able to say I have tried it. Well, the crazy thing shoots about 1/2 inch groups as 100 yds. Kicks about like you would expect, but I can accept that for the results I'm getting.

Anyway, now I don't want to change anything-----at least until the plastic stock/bedding gives up.

As for the .300 Weatherby, I'm finished with it in the standard chamber configuration.........there WILL be others with different experience, but this is what I have experienced.

The .300 Wby has been used for 1000 yard competition in custom built rifles, but I'm doubtful that the standard reamer (freebore) was used.
If a different reamer (no freebore) is used, I would not shoot factory (or factory equivalent) ammo in it.

Cheers,
Jim
 
Thanks Jim - sounds fairly consistent with what I heard from other folks....

Trouble is I'm smitten.....so may be a case of making the best of it! I will be reloading (as I would need a mortgage for factory ammo) so will be able to optimize my load....in any case sounds like I need to 'manage' my own expectations...

Cheers,

Jason
 
My current field rifle is a custom 300 weatherby built on a remington 700 action and I love this round and rifle. It keeps sub 1/2 moa all day long (and sub 1/4 when I am really on my game). I have effectively shot the rifle out to over 1200 yards and have no issue going further.

There are two schools of thought on this. I'll start with mine:

With the 300 wby you can get 3100 fps out of a 200 grain bullet, though you might have to load longer the max magazine length. And I can consistantly get 1/2 moa accuracy out of my rifle. I also love the brass selection. Other then the Win mag I know of no other 30 cal magnum that has better brass selection. Ultimately I would not consider myself under-gunned while taking any game in North America with this round, and it is capable of taking most african plains game.

The other train of though:

Some don't like the double radius neck on the weatherby and simply refer to it as "silly". They also contend that they can get better MV out of the RUM, which you can, but at the expense of significantly more powder. They also contend that other rounds are more accurate (I have not found this to be true) and easier to handload. Which I agree with the handloading part, belted magnums are bit more work when loading them.

In the end it is personal decision of what round you like or don't. But if it were me I'd keep this round, it is a really nice round.
 
I don't have a lot of experience with the 300 Wtby, so I should maybe keep my mouth shut. But I am currently trying to work up a load in a client/friend's rifle, a Weatherby Mark V.

First problem is that the magazine is very short for the amount of throat in the chamber. In order to fit the magazine the bullet has to be loaded .275" back from the lands. Weatherby does this on purpose to use the long throat as part of the combustion chamber and enable them to put more slow burning powder in their factory ammo. But what this does to reloaders is greatly reduce velocity.

I started out with a medium load of RL19 and RL22 with the 180 gr TTSX and the 180 Accubond

TTSX - RL19 - 77 gr - 2906 fps
TTSX - RL22 - 78 gr - 2858 fps
AB - RL19 - 77 gr - 2899 fps
AB - RL22 - 78 gr - 2851 fps

So this told me that the rifle does not get much velocity so I did a 1 shot per load Audette ladder with the TTSX going up in .3 gr increments

TTSX - RL22 - 78.0 gr to 80.1 gr (0.1 gr over book max) - 2824 fps to 2923 fps
TTSX - RL25 - 79.7 gr to 81.5 gr - 2807 fps to 2806 fps

now the velocity is still way low even though Nosler #5 manual say 80.0 gr RL22 is max and gets 3132 fps. ***

So next I have continued the ladder up in RL25 (which showed the best results on the target and is more available than RL22) and found some IMR7828 to try this ladder next

TTSX - RL25 - 81.8 gr to 84.5 gr
TTSX - IMR7828 - 83.3 gr to 86.0 gr

Book max for the IMR7828 is 84.5 gr and shows 3185 fps. I will shoot the IMR7828 loads and look for pressure signs on each case as it steps up.

Now what I am trying to say is that this is a lot of useless shooting in order to get velocities even up to 300 win mag standards. Frustrating as hell and I don't like to go over book max, especially in someone else's gun.

Like Longshot said, the brass is excellent, very consistant neck thickness. But I will never buy a 300 Wtby myself.
 
Woods what length barrel are you working with? I am getting 3024 fps with 84.5 grains H1000 pushing a 200 grain accubond out of a 26 inch tube. Thus your velocities are running WAY low.
 
Woods what length barrel are you working with? I am getting 3024 fps with 84.5 grains H1000 pushing a 200 grain accubond out of a 26 inch tube. Thus your velocities are running WAY low.

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.
 
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.

.
 
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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.
 
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