Sighted in the new Model 70 in .270 WSM today, and the first handloads, WW case, WLRM primer, 60.0 grains Re19 and Nosler 130-grain BT gave me three inches at 100 yards.
Back to the manuals ...

Why not load starting w/ a starting load, load 5 cartridges, load 5 more w/ 1/2gr more powder and so on. Going out w/ 4 to 6 different reloads makes it easier. When you find a load that works ok, start there. Load 1/4gr up and 1/4gr down. It will narrow it down really fast. Even graduate by 1gr.

-.0275 off the lands.

Nosler manual says R-19

Starting 61.5

Accuracy load 63.5

Top load 65.5

All good thoughts guys. Didn't expect to find acorns the first time out -- just seeing how she handles.

Why did you go with just one bullet for the first trip?

I strongly believe in the principle that the rifle selects the bullet that it likes best and then the shooter fine tunes the loads.

I usually take a few loads of say 3 bullets I plan to use. Usually I will have Remington CL as the bulk shooting bullet and then TSX and may be Accubond to use on hunts. JMTBW

Good luck with the new rifle.

Naki: I had a couple of other guns to work with, so just loaded 10 rounds for the WSM to start to get a feel for it. You're right about trying a variety of bullets. I have usually had very good luck with Nosler BTs for accuracy, if not game performance.

A couple of different thoughts, in addition to what has already been offered:

I have seen several rifles refuse to shoot with any real accuracy until the barrel was broken in. On occasion that took as many as 50-60 rounds.

Your load is below minimum. I am thinking that as you up the powder charge the bullet will be traveling faster, spinning faster, and accurcy will improve. If groups tighten, then open back up, you have exceeded the max accuracy load for that bullet/case combination.

I like my projectiles seated .010" off the lands, but that is pretty tight so load accordingly and watch for pressure signs.

And lastly, I wouldn't shoot but three or four at each powder charge. Bullets get higher all the time, and three shots will tell you all you need to know.

Good luck. The 270 WSM has the reputation of being incredibly accurate and hitting like Thor's hammer.

quote:

Usually I will have Remington CL

Both my brother and I have laughed at how well our guns shoot factory Core-Lokts. Whenever we shoot the premium stuff and it doesn;t pan out we just curse and grab a box of CL's and the damn things shoot MOA.

You mentioned it was a new rifle. The group that you got, was it round, vertical stringing, horizontal stringing,what? Remember the reason Winchester folded the last time was very poor quality control. I would definitely make sure the bedding is good. I had a similar thing happen with a new Model 70 Featherweight in 7x57. I took the action out of the stock and found where the recoil lug was bedding with some kind of epoxy, just a dab, and that it was soft like silicone we use from a caulking tube. I decided then to bedded the rifle which I did and it starting shooting really well for a light sporter barrel. I'm not saying this is what is the matter with your rifle, but it's worth checking to make sure the bedding is good.

You might also try Reloader 17. I've gotten some excellent results with it in my Kimber 270 WSM.

Firstly, I should mention that I only use 150 gr. bullets in my .27 cal. rifles but maybe my comments will help.
My .270 WSM is an Extreme Weather and I've tried a fair number of powders. Running your numbers thru my copy of Quickload, it predicts a velocity of 2950 fps. Rather anemic, IMHO. My .270 Win. gets 2930 with a 150 Partition, I think you should safely be getting more.
I've tried a fair number of powders in my WSM and for the most part have found the Reloader series lacking in either velocity, accuracy or both, up to & including Rldr-25.
I'd suggest that you look at slower powders such as IMR-7828, Retumbo, or, perhaps Magpro.
With 150 gr. bullets in my rifle, I get the best accuracy/velocity with a near max. charge of Retumbo with IMR-7828 coming close. Didn't have good luck velocity/accuracy wise with Rldr-17 & a 150. gr. bullet either.
Just what I've found. Good luck.
Bear in Fairbanks

Thanks for all the advice, guys. Yes, this is a new rifle, and I did not do the normal shoot-clean-shoot break-in. These were the first 10 rounds through the gun, and the necks were smokey, indicating low pressure. The gun has the same Bell and Carlson aluminum-bedding block stock as your Extreme Weather, Bear, so I expect the gun to be accurate once I find the right powder and bullet combo.
Groups showed no stringing horizontally or vertically, and I think that might reflect low pressure, too.
My goal is a good flat-shooting 130 or 140-grain load for open country deer and antelope and then see what I can do with that 160-grain Partition for the big stuff.
As my late grandmother would say, "It's early days yet."

Bill:
As an addendum, I'm getting about 3120 fps with a 150 Northfork and 68.0 grs. of Retumbo. About 2 grs. under max. Seating depth as measured to the ogive is 0.025" off the lands. Getting easily 1 MOA out to 300 yds. which is as far as our range goes. Good luck.
B.I.F.

H4831sc is working good with 140 BT's in my Remington 700. I just finished loading a batch of 140BT's and 150 Partitions with Retumbo.

Donald: Think I have som 4831 SC in the shop ...
Bear: Looks I'll need to try some Retumbo all right. Those North Forks are fabulous bullets made here in Oregon.
I look forward to getting this rifle dialed in.

Bill,
I also have some 130 grain Partitions coming from Shooters Pro Shop and plan to try them with IMR4350 as well as H4831sc. I will keep you updated to my findings.

H4831sc and IMR4831 work well for me in both of my .270 Win's with 130 gr Partitions.
RL 19 works very well with 130 gr Partitions in my .270 Weatherby.

Might check the bedding. 3" seems a bit odd even for a starting load.

Try RL17 too. It was specifically formulated for the WSM's.

I load a 270WSM for a friend. IMR4350 + 140 gn Accubond = 3/4" groups.