A friend asked me to do some load work on his Winchester Shadow in 25 WSSM. Well, this rifle has some ISSUES! However, this could just as easily apply to any other rifle as well, not just a WSSM.
First, the factory beding was poor, and actually had the action in a bind. There was bedding material under the recoil lug, and in a few other places it didn't need to be. I managed to clean that up, and while doing so, cleared up a feed-from-the-magazine problem it also had.
Generally, the three types of factory ammo tried give 2-3" groups. Also, bolt lift with the factory fodder is pretty stiff! Enough so, that I think it may be a problem for his daughter, for whom the gun was bought.
I've worked up a few loads with the 100gr Sierra FB, and grouping doesn't get much better. Powders tried were IMR 4895, 4350, and 4831. Each was tried in a ladder work-up, from start to max listed, a grain at a time. A LOT of cooling time was consumed, with the itty bitty skinny barrel, which btw, is floated enough so you could throw a cat through it! I tried some shims under the forend, and things only got worse... Ditto for boattail bullets (4-5" groups). Velocities with reloads didn't approach factory loads, but neither did bolt lift.
Another thing, resizing cases fired in this rifle takes an inordinate amount of effort, even with the Rock Chucker, and using Imperial lube. I suppose the chamber is a little generous, and the die maybe a bit tight? Think sending the sizer back to RCBS and having it "adjusted" might help here?
I haven't reached the point to where I can start futzing with COAL, or primers, no need to get there until I can get groups down to 1-1 1/2?
This one has me scratching my head, and twisting what little hair I have left. Other than changing bullets - which is next on my agenda - can y'all think of anything I've overlooked? Ya' got any experience with these rifles/cartridges? All opinions & suggested invited, and appreciated. Thanks,,,,,,,,Bug.

Bug,

Do you know the twist rate on that rifle?

I might start experimenting with the 100 grain Barnes TripleX if I were you.

They are as long as the Nosler 120 grain bullets, and do well in my rifles 1-10" twist.

Start off with the bullet just touching the lands, and back off to about 0.02 or 0.03 deeper into the case.

My impression with this round is that it will perform best (accuracy wise) with loads that are approaching the higher end of the SAFE pressure curve.

I have wondered how Reloader 19 might do in this case.

Please let us know how your experimentation goes.

Garrett

I would send it back to winchester with a nasty letter then go buy a remington.

A Remington in 257 Roberts.