Loading the 300 WBY Magnum, what would you do?

[DoneNOut]

Friend of mine inherited his uncle's cherry condition (maybe shot 12-15rnds) Weatherby MK V with original German scope, 300 WBY and wants me to load for it. SO, I could be all boring and research my manuals and such, but I'd rather see what you all recommend.

Brass: Weatherby 300WBY (new)
Bullet: 200gr ELD-X
Powders: H1000, AA4350, N570, RL-25
Primers: Fed 215 and WLRM

Factory 200gr ELD-X cartridge showed 75.2gr of an extruded powder. Who knows what, but the grain weight used gives an idea of burn rate.

So, lay it on me.

 

[JMW67]

you may want to check the twist on that barrel the older weatherby rifles were slow twisted

 

[DoneNOut]

you may want to check the twist on that barrel the older weatherby rifles were slow twisted

Its a 1972 model...

 

[Dr. Vette]

I'd still check the twist, though likely 1:10.
RL-25 is likely your best bet.

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[340Wby-4-everything]

I helped a friend with a late 60's vintage 300Wby Mk5, It will shoot sub .75 moa with both factory Hornady 165 and 180 gr rounds. If you want me to find out what they were exactly, let me know and I'll ask her. Odds are bad for it to stabilize 200gr and greater, but you don't know if you don't try.

 

[Lefty7mmstw]

rl25, rl22, 7828, etc. will all do fine. h1000 might just want to play too here. The 200 eld-x can be a fussy pill in the bigger chamberings. A 200 smk or hdy hpbt might be easier to tune.

 

[MagnumManiac]

I would send an email to Weatherby with the serial number to determine what twist it has. I have seen many 70's era German made Mark V rifles that had 1:12" twists.
They have trouble with mono's and long 200+g bullets.
You also need to check throat length. Standard is 3/8" long, but I have seen them with 1/2" too.

Cheers.

 

[wv270wsm]

Just load up some 180 gr Hornady sp and go kill whatever steps in front of ya . That's what my dad hunted with for 30 years . Never had anything take a step after the shot all bang flops . I know he used an imr powder but don't remember which one

 

[bigbuckfarm]

I have had good luck with RL25 and Berger 210 VLD's in a newer Weatherby with 1-10 twist.

 

[roninflag]

87.0 Re-22 and a 168 barnes. fed 215GM. weatherby brass

 

[Old Rooster]

I loaded some 300 weatherby today for a Vanguard(Howa).
I used Re22 76.2 grains and loaded to 3.560.
I started at 75.0 grs and worked up to 76.2 with no hard bolt lift or any other over pressure warning signs.
Shoots right under 1/2 an inch at 100.
I just got my new Weatherby (Norma) brass but have not even opened the box yet.Still have unused RP brass.
Old Rooster

 

[walter351]

This is for German built rifles

 

[Ricky C]

Hey, I used a 180 gr Nosler partition with 82 grs of RL 22 for years. Changed to a 180 gr TSX with 82.5 grs of RL 26 a few years ago. They both grouped under an inch and both killed everything I shot at. The 26 is more temp stable, got tired of rezeroing when it got cold here. Good luck and Take Care, Rick

 

[Can2Juan]

My dad and I have been loading for our old 300 bees for 5+ years, best loads have been with IMR 7828, anything under 200 gr bullets. My rifle loves 82.5 gr with 180 gr TTSX, loaded just short enough to clear the mag well, will sub 1/2 at 100 yards. Im currently in load development with 181 hammers, not going great but I'm trying, I might have to go with the 180 hammers .