Is there trick to loading 257 WM

[Canhunter35]

Another vote for 7828. I had good luck with it. Best accuracy I ever achieved was with 115 ballistic tips and 115 vlds in my 257.
Try crimping the cannelure on those 100gr tsx at the recommended seating depth. And run enough powder, wby typically don't like light loads

 

[bob4]

It seems so strange to me that he has tried so many of the powders recommended here. I don't wonder if something is amiss with his scope. He's a good shot ,certainly off a rest and reloads well enough. His scope is a brand new Swaro Z-6. He had a load shoot a clover leaf one day and asked me to shoot the same load a week later and it was off x over 2 in. I will see him tomorrow and will get his notes and see all what powders he's tried. I thank you all for the info. Please keep it coming.

 

[bob4]

https://thefiringline.com/forums/showthread.php?p=4928827#post4928827

Was this a warning on a powder ?

 

[Canhunter35]

It seems so strange to me that he has tried so many of the powders recommended here. I don't wonder if something is amiss with his scope. He's a good shot ,certainly off a rest and reloads well enough. His scope is a brand new Swaro Z-6. He had a load shoot a clover leaf one day and asked me to shoot the same load a week later and it was off x over 2 in. I will see him tomorrow and will get his notes and see all what powders he's tried. I thank you all for the info. Please keep it coming.

By what ur saying I would be checking the scope and mounts. And clean the rifle, it could be fouled enough it's not grouping

 

[MagnumManiac]

Can't seem to find info for this bullet and retumbo.

You may have to extrapolate loads for another bullet or forget Retumbo all together.

Cheers.

 

[243winxb]

Was this a warning on a powder ?

Its more than light to midrange charges of powder that may be a problem. The slowes burn rate powders are not always good for light bullets, with little shank in the case necks.
Light neck tension may let the bullet move at primer firing, causing a pressure spike.
A magnum primer is a must.

From the link. The Collapsed Shoulder is in an old Speer manual. Light loads & slow powder are the cause. Use a faster burn rate of powder. Pressure is low & neck not expanding to seal. Make sure the bullets have enough neck tension. The expander should be .002" smaller than bullet diameter. This will keep the bullet from moving when the primer fires. What is your COL? The bullets bearing surface should be in full contact with the neck. If seating the bullet long to get close to the lands/rifling there may not be enough shank of the bullet in the case neck.

 

[bob4]

Brought the rifle home tonight and ran into something different, for me anyway. To touch the lands is 2.715 ( ogive) back off .030 and were ok back off another .020 and there isn't much bullet left to go further. Seems odd to me. I will say while it hits lightly at 2.715 it will go much further before a hard stop. On the way to this hard stop sometimes the bullet sticks while backing the gauge out and sometimes it doesn't. When you reach the hard stop it always sticks there. I don't know enough but, is there a chance there is something like a tiny burr in the way and 2.715 isn't the lands?

 

[243winxb]

The Weatherby cartridges chambers are designed with extra free bore.This to reduce pressure.

It is a mistake to try and reach the rifling. This also applys to many factory chambered rifles. Especially with light for caliber bullets.

Bullets from 75 GR TO 120 gr may be loaded in a 257 . The 75 gr is going to have the most jump to the rifling.

 

[243winxb]

When you reach the hard stop it always sticks there.

The free bore will measure same as the bullet diameter plus about .0005" on a good chamber. So yes, its possible for the bullets to stick there. More so if wet with oil.

 

[243winxb]

100 gr Barnes ttsx

may preduce heavy copper fouling. Use a good copper solvent to remove all fouling.
Longer then lead core bullets. They may need to be seated to SAAMI maximum OAL of 3.209" They must fit and feed from the magazine.

If any bullet is seated to deep, it may fall into the brass, if the powder doesnt stop it. The neck looses contact with the bullets bearing surface.

" Its a cooper rifle" Not all brands of rifles will have the Weatherby "free bore". Remingtons do not.

I hope all this makes sense, helps.

 

[Canhunter35]

Brought the rifle home tonight and ran into something different, for me anyway. To touch the lands is 2.715 ( ogive) back off .030 and were ok back off another .020 and there isn't much bullet left to go further. Seems odd to me. I will say while it hits lightly at 2.715 it will go much further before a hard stop. On the way to this hard stop sometimes the bullet sticks while backing the gauge out and sometimes it doesn't. When you reach the hard stop it always sticks there. I don't know enough but, is there a chance there is something like a tiny burr in the way and 2.715 isn't the lands?

If that's your concern, get a smith to bore scope it.
Personally, I would try a few more things first. Including a different bullet.
Check out hammer bullets 92gr hammer hunter. It'll fit the profile of fast, copper bullet and may work better than the tsx

 

[243winxb]

All copper bullets
Copper eraser in smokeless powders. Some use Tin Dioxide.

Copper Fouling Eraser ingredient, originally used in military propellant, which greatly deters copper fouling and contributes to longer periods of top accuracy with less barrel cleaning time ,for rifles.

Use powders like-

Alliant's -Reloder powders have it, except 17.


All Vihtavuori reloading powders produced today have an added decoppering agent, also called anti-fouling agent.

Google the MSDS or SDS and check chemicals used in other powders.

 

[bob4]

All good info. Thanks. I'll get some copper cleaner down it's throat. Buddy told me there have been 20+ rounds through it since cleaning. I'm pretty sure that the "Hard Stop" I feel is the lands and the other will need investigation. I have 1 other bullet I checked and the same thing happens. Short distance to a bump and a slight push and then it travels all the way to the lands. And as usual 243 is correct. You couldn't load this bullet anywhere close to the lands. The grey portion of the OAL gauge is all but out of the red tube. I will add to that .260 and start from there as long as magazine accepts that.

 

[bob4]

We shot it today with 70gn H-1000 and think I have a distance from the lands to work with. 2 3shot groups came in @ 1.3 and .9. I don't think that's a bad start. The other 4 groups didn't come close. I don't suppose Berger 115 would stabilize in a 1:10 ?