Having issues with 300 Weatherby Mag, Figured out!

walleyed99

walleyed99

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So far I have tried a handful of different loads for this rifle and have not been able to get anything to group worth a SH!T, I have taken recoil out of the equation by using a lead sled as I after about a 3-4 different loads I couldn't get a 3 shot grouping of less than2.5 to 3 inched at 100 yards. I have never been recoil sensitive but thought maybe that was it and still NOTHING. Any PET loads, loads that people have had work in various different 300's. Anything to maybe help out would be appreciated. So far I am kinda lost for ideas. Looks like the 308 is coming moose hunting in a couple weeks....
 
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Couple things I can offer up....
Ditch the lead sled, you can crack stocks and break scopes with heavy recoil rifles.
Use the slowest available powder you have access to, something that will be 80-90gr of powder and fill 95% of the case. Load up 165, 180, and 200gr pills to see what it likes.
Forget published OAL, seat bullets so they just fit the mag box, WBY has looong throat's.
Tighten all your optic bases and ring screws again.
For the action screws, front should be a bit tighter then the rear. So tighten front first snug plus a bit, rear just snug.
If it's a Vanguard check that there are no high spots in the barrel channel. It's supposed to be touching the barrel evenly the whole length, sometimes they get a little over lapped when molded together.
 
WBYs have a long throat and are built to jump into the lands. I find that length is more important than speed when building a WBY load. Pick your bullet and powder, ramp up your powder using a ladder test watching for pressure but dont get to concerned at this point with group size. Use book OAL for this part. When you get powder figured out start with longest OAL that will fit in Mag and work backwards in .05 increments from there from there. WBYs can be tricky (Mark Vs, I dont know about vanguards) but this "backwards method works pretty good. Only ever change ONE VARIABLE AT A TIME.
 
Hitzy said:
Couple things I can offer up....
Ditch the lead sled, you can crack stocks and break scopes with heavy recoil rifles.
Use the slowest available powder you have access to, something that will be 80-90gr of powder and fill 95% of the case. Load up 165, 180, and 200gr pills to see what it likes.
Forget published OAL, seat bullets so they just fit the mag box, WBY has looong throat's.
Tighten all your optic bases and ring screws again.
For the action screws, front should be a bit tighter then the rear. So tighten front first snug plus a bit, rear just snug.
If it's a Vanguard check that there are no high spots in the barrel channel. It's supposed to be touching the barrel evenly the whole length, sometimes they get a little over lapped when molded together.
Click to expand...

This^. And try another scope if you have one handy.
 
Thanks HITZY, I will give all of that a once over, Gonna pick up some 180's and 200Gr's on way home from work. Any suggestion on Bullets? I was thinking Partitions, or Sierra Gamekings if I could find them.
 
walleyed99 said:
Thanks HITZY, I will give all of that a once over, Gonna pick up some 180's and 200Gr's on way home from work. Any suggestion on Bullets? I was thinking Partitions, or Sierra Gamekings if I could find them.
Click to expand...

Sierra is generally the go to for accuracy, I'd try some of those.
 
I have been using the 300 Wby for decades, try RL 25 powder if you can find it, with 200 gn Accubonds or Partitions, if you can find them. The 300 Wby groups it's best (in three different rifles) at max loading or, if you are an experienced hand loader and can read your pressure signs, even above book max.
All of my 300s have shot significantly better with forend tip pressure on the barrel, about 6-10 lbs. Just cut about 3 or 4 squares of electrical tape and stick them (stacked) in the bottom center of the barrel channel about 1" back from the tip and try that, you can try more or less but very light hunting barrels usually like this a lot. The difference between 2 1/2" groups and 3/4" groups in several of my rifles.
For a cartridge in this recoil class and velocity, bedding is extremely important, have you bedded the action?
I have never found the 300 Wby or any other Wby cartridge to be particularly difficult to get good accuracy from, but the platform must be well mated.

This is how mine shoots, this is with about 10 lbs of forend pressure.






You will note that my COAL is 3.95, I have lengthened the bolt throw and action opening and magazine to 4" on this rifle and seat my bullets out to just shy of the lands about .010"
 
In my rifle groups improve at maximum loads .
My best group was when bolt was hard to open .
Right now I'm shooting maximum loads with out bolt sticking .
 
Whats the history on the rifle? Was it new or used, Vanguard or Mark V, and has it ever shot anything well? People tend to dump guns that don't shoot, and not all accuracy issues can be fixed on the the reloading bench. Many need to be patched up with popsicle sticks, and others need to meet a good pipe fitter.

For the longest time much of Weatherby's reputation was based on factory loads with mostly Hornady and Nosler Partition bullets. Flat-based bullets with long bearing surfaces tend to tolerate the long lonely jump to the rifling better than the latest VLD style, pointed at both ends wonder bullet. If it doesn't shoot one of those 2 bullets, or a TSX which also thrives on the long jump you might want to start looking at the gun.

Couple random thing;

7828 seems to produce results with so many Weatherby cartridges that I'm almost getting superstitious about it.

Weatherby rifles can be very sensitive to action screw torque. The recommended torque sequence is backwards to just about every other rifle; and sensitivity to torque screams bedding issue. Just throwin' it out there.
 
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I too have gotten excellent results from IMR 7828 in my 257 and 300 Wbys, but I have changed to RL 25 in both and have gotten great accuracy and another 150 fps or so along with better temp sensitivity characteristics.
 
Weatherbys test loads for the .300 'bee are their own 180 Spire point (Hornady) and the 165 TSX. Food for thought. When you stray away from the Weatherby calibers you might as well start chanting Federal and Federal plus TSX because its a recurring theme.

Thats what they use to decide if a guns broken or not. Just sayin'.
 
when my markV was new i was having a similar problem a friend told me to switch to non boattail bullets, and that cured my problem. a friend of mine was having issues with a couple of his friends 30-378's and i told him my story when i seen him later
he said they tried it and it worked. this might not apply to your situation might be worth a try
 
Hitzy said:
Couple things I can offer up....
Ditch the lead sled, you can crack stocks and break scopes with heavy recoil rifles.
Use the slowest available powder you have access to, something that will be 80-90gr of powder and fill 95% of the case. Load up 165, 180, and 200gr pills to see what it likes.
Forget published OAL, seat bullets so they just fit the mag box, WBY has looong throat's.
Tighten all your optic bases and ring screws again.
For the action screws, front should be a bit tighter then the rear. So tighten front first snug plus a bit, rear just snug.
If it's a Vanguard check that there are no high spots in the barrel channel. It's supposed to be touching the barrel evenly the whole length, sometimes they get a little over lapped when molded together.
Click to expand...

I disagree with ditching the Leadsled. People blame cracked stocks, and broker scopes on the leadsled. True that may have caused the odd one but the main reason is that people over-weight the sled. I have shot everything from 7mm Rem Mag up to 450 Rigby and have yet to have an issue. You need to let the Leadsled "recoil" which include allowing it to move. When shooting my 458 Lott and 450 Rigby the 'sled still moves back 6" with 75lbs on it. Caldwell said not to go above 75lbs. If it's anchored with too much weight the stock takes too much tourque and may crack. A good way to tell if there is too much weight on the Leadsled is if the rifle jumps forward when you shoot it.
I agree with the responders about trying different OAL's and make sure you all screws are tight. I have a Weatherby VG2 in 300WBY and it shoots lights out. Are you using a scope if so maybe try a different scope?
 
It's a weatherby sub MOA vanguard in the Bell and Carlson stock. I took on trade from a fellow who a friend knows and said friend has apparently shot this rifle and said it shot good. Recoil was too much for the guy as he is a smaller fellow. I took out of stock checked the bedding and it seems solid, action screws were probably not at spec so it could be that. Reinstalled in stock and torqued and will try out the 3 different powder and bullet choices and see if there is any improvement. Thanks for the tips so far fellas, hopefully will figure it out.
 
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I have 3 rifles chambered in 300 Wby and they all shoot 180 gr TTSX bullets into nice little groups with 7828 powder. RL 25 powder is also good if you can find it. One thing I have noticed that makes a difference in the 300 Wby is the PRIMERS you use. I have found that my loads in the 300 Wby are more consistant (better groups ) when I use the FED 215 primers. Same story on all 3 rifles.
 
Thanks Douglas, you are one of the very few on here who express the same views that I have stated so many times on here; bedded rifle, pressure under the front of the barrel and heavy loads for accuracy.
Bruce
 
Happy to report, that the accuracy issues must have been due to be mpropper tourqu even specs on the action screws. Has 3 differently 3 shot groups with 3 different loads shoot sub MOA, or on the verge of sub MOA. Was rainy and miserable, so just tested the faster couple loads for each of 3 calibers before going out hunting next weekend. Have a nice 180grain Sierra Gameking, and a nice partition 168 grain load ready for hunting next weekend, just have to load a batch up. Thanks for the help guys!
 
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