300 Weatherby Load Help

[Rymart]

The barrel is only partially free floated. The action and the first inch of the barrel are bedded, the rest of the barrel is now completely free floated with about a 1/16th of an inch gap between the barrel and the barrel channel.

 

[Rymart]

The rifle is a Mark V Fibermark (I think). My main objective in the load work up was to verify that the rifle was capable of MOA accuracy, which until now it looked like it wouldn't be. I'm not sure if I'll hunt with it again or just sell it to fund my 338LM project. Still trying to figure that one out.

So you're saying that the 180 gr. SGK's at 3100 to 3200 fps MV would not make for a good hunting bullet? Just confirming.

 

[Hired Gun]

This 257Wby Accumark is bedded 100% contact around the lug and 1 1/2" under the chamber and then a pinch of bedding under the rear of the action. It fits very tight into the stock. The rest of the barrel is near 1/8 inch of clearance. Free bore? No problems here. These bullets are jumping near .500" 75 grain V-Max's at 3960.

 

[Hired Gun]

For elk or bigger the 180 Game King at 3200 inside of 200 yards won't cut it on an off angle or shoulder shot. Push out the range or keep it in the ribs for a double lung or neck or head shooting and it will be fine. For elk I'm thinking if you can get the impact speed under 2400, it would perform much better. At 3200MV that speed (2400) is around 400 yards. We have blown a lot of them up on 100 pound black tails. It kills them quick but you can take the edible parts home in your lunchbox.

 

[victor]

Hi Fishry,

I have a .300Wby in the ultralight weight configuration.

My rifle likes 2 types of bullets with the same powder charge.
Powder: Norma MRP - 84.5gr
Bullet: Barnes TSX - 180gr. or Nosler Accubond - 200gr.

I get my best groups with this powder and bullet combinations.



Having said that, I need to inform you that Norma MRP powder is not available in the U.S. anymore. I did read somewhere on this site that somebody else other than Graff & Sons is supposed to start selling Norma powder in the states again, but I don't know who that is.

If anybody has info regarding where MRP can be purchased, please let us know.

From what I have heard, Reloader 22 is supposed to be the same as MRP, except that the quality control standards for producing MRP are supposed to be higher. I have used Rel22 as a substitute for MRP, but I do not get the same groups as with MRP. Something is slightly different.

Also, Hired Gun, May I ask what your.257Wby recipe is. I have not had any luck getting mine to shoot with any bullet lighter than 115gr. My best .257Wby load is 70.5gr of MRP with 115gr TSX bullet. This combination gives me 5/8" groups.

Oh, one more thing, as stated previously, you do need forearm pressure on your barrel. Approx 14lbs, if memory serves me correctly.

Regards,
Victor

 

[Hired Gun]

My super tack driver recipe for the 257Wby is as follows.
From brand new the only brass prep has been a light inside chamfer. I never clean primer pockets or trim necks. I use only Weatherby brand brass.
The best accuracy comes from used brass so it fits my chamber perfectly. I do tumble it until is is highly polished. I don't think that helps accuracy much but it makes me feel better about my loads if they look nice. The brass is neck sized only in a Lee Collet die. Then I add the following:
CCI-250 primer.
77 grains of RL-22
75 grain V-Max seated at 3.250"

I do use a Black Diamond 8-32 scope on this one so I can see what I'm doing very well. Other than the first 1 1/2 inches under the chamber that is bedded the rest of the barrel is generously free floated. My other two Accumarks are completely free floated. All my Weatherby like light bullets but they are not practical for anything but varmints. I use 100 grain Partitions because I can get them cheap. I believe the 100 grain Barnes triple shocks are more accurate for a deer worthy bullet.

 

[locknloadnow]

I'm going to give my troublesome 300 Weatherby Mark V one more try to shoot accurately (by that I mean under 1 moa) and I really need some help with working up an accurate load for it.

Here is what I have to work with:

175 gr SGK's
180 gr SGK spbt's
190 gr SMK's
185 gr Berger VLD's

20 pieces of new Weatherby brand brass that I have BR prep'd.

Federal 215 primers.

1 lb of RL19 powder

I'd also consider purchasing a lb of IMR4350, RL22, RL25, or H4831 powder if any one of these came highly recommended for this caliber.

I would really appreciate any 'pet' load recommendations. My main emphasis, for now, is accuracy, not velocity. I would also appreciate recommendations on a powder that will excel with this caliber. I do not have any load data on the berger VLD's (as they were given to me), and would like some help on where to find load data or starting points for these.

I'm a careful reloader and would start low and work up to any recommended loads. And I would consult the books.

The past accuracy problems with this rifle are a whole other story. At this point, the action and the first inch of the barrel are bedded. The rest of the barrel is free floated. The action screws have been torqued. The scope and mounts have been swapped, just in case they were part of the problem.

this is an old thread but worth reviving, the first thing I'd do is choose a lighter bullet i.e. 130-150 grain, preferably 150 grain- and start with the slowest powder, starter loads, working up to maximum load for that powder. If a reduced pressure load doesn't give accuracy, a maximum load rarely will either. That's just my own personal experience. And my own rifles always shoot better with lighter bullets in the 120-165 grain range. When the bullets get on the heavy side, the recoil goes up too, and it's not conducive to accuracy. Forget velocity, the load that kicks the least, usually is the most accurate, because you'll shoot it more comfortably.

 

[alaska]

My Favorite load

300 WBY
26" barrel

Reloader 25 @ 85.0
200gr Speer SP
Fed 215GM
WBY brass

3000 fps load

 

[alaska]

my 300 works well with the following--

180 gr. nosler part.
federal gm215m primers
80 gr, h4831sc powder

3005 fps on my chronograph

saami oal used

Under loaded