Accuracy problems wby 30-378

[Plugdumper]

Have done everything that I can think of from copper fouling to set scews in inch pressure. I'm stumped. Can anybody offer any help. Working with Barnes 180 gr ttsx, h-50bmg, fed215m primers, wby mark 5 rifle. Thanks for any advice ahead of time.

 

[Broz]

Loose the H50 BMG, I would go to 98 gr of H-1000 and a 210 Berger after a good cleaning with BoreTech Eliminator.

Or another good load is a 230 Berger and 94 gr of H-1000.

Seat both at 3.800" OAL

>>>>>> As always work up to this charge.<<<<<<<<<<

We have shot 1 moa or under with both loads at 1000 from factory Accumarks.

Jeff

PS: if this is a factory Accumark they always shoot better after bedding the Front Lug area.

 

[Plugdumper]

Thanks I will give those a try.

 

[madman]

I second what Jeff said...



--md

 

[MudRunner2005]

PS: if this is a factory Accumark they always shoot better after bedding the Front Lug area.

Hmmm, this might be why my groups are jumpy from 1/2 to 1 MOA with my .257 Wby Accumark. I mean, 1 MOA @ 100 is only 1 inch, so the groups are still fairly tight, but I think it could be better. Guess I'll take it to my smith and have him bed it while he's working on my other builds...

 

[Salar600]

PS: if this is a factory Accumark they always shoot better after bedding the Front Lug area.

Could you post a pic of the beding of this rifle. I bought a use one and I'm not sure if it as been beded or not.

Thanks, Mart

 

[Broz]

Could you post a pic of the beding of this rifle. I bought a use one and I'm not sure if it as been beded or not.

Thanks, Mart

Take it out of the stock and look. They come with an aluminum bedding rail in the stock that fits like a sack on a sow. If there is bedding compound around the front lug area somone has bedded it. If it is all aluminum it needs bedded.

Jeff

 

[Salar600]

There is definitely compound but only around the screw hole and behind recoil lug. It is not a full bedding like I am use to see.

Thanks

 

[Dr. Vette]

There is definitely compound but only around the screw hole and behind recoil lug. It is not a full bedding like I am use to see.

Thanks

That's probably the dollop of white-yellow-greenish stuff that Weatherby puts in there. I find it usually is cracked if the rifle has been used, and is of little good.

Bedding at least the recoil lug, if not the action, will definitely help. This is especially true on a 30-378.

 

[idaho elk hunter]

How many rounds has the barrel had through it. If the round count is low I would inspect to see if the RECEIVER was threaded square with the bolt face. I have had 3 30-378 that were good enough to met quality control inspections but definitely not good enough for sub moa. If this is the case Weatherby will true and thread correctly. All other replys are good but will not fix any machining issues. On a side note The 30-378 is the most problematic out of all hunting caliber Weatherbys. This is due to powder that is being used to get the highest velocitys. Many people shoot tight groups at 100 yds and finalize there. I would strongly suggest looking at some Norma powders followed buy the Hodgen extruded lineup. Switch to Win MAG primers. And load to 3.8 to 3.85 coal depending on the manufacturing tolerances of your box. Let us know how it turns out...

 

[lloydsmale]

my suggestion would be to try a diffent bullet. In my experience either a gun loves barnes bullets or hates them. You can throw alot of money out there buying barnes bullets try to find that majic load that may never come.