Home Forums Reloading Big Game Rifles 358 Wincheater Sierra data needed

I am loading up some loads for the 358 winchester using the 225 grain Sierra gamekings. Those have a boattail so I was wondering what the sierra manual had for those. I am using both 4064 and win 748 powders. Am a bit afraid to go off of Speeds manual with 220 grain because that is a shorter bullet. And hornady does not have a 225 grain bullet.

My copy of the Sierra #5 manual only shows data for IMR 4064
Start: 41.8 gr./220 FPS Max: 48.0 gr./ 2400 FPS

Latest Nosler manual shows data for W748 for their 225 gr. bullet.
Start: 44.5 gr/2292 FPS Max:48.5 gr./2426FPS

You can either use the Nosler data by starting low and working up or calling Sierra and asking if they have data. Best I can do for you.
Paul B.

Thank you!

I've heard IMR3031 is a go to powder.

Google Sierra’s load data.

I interchange a max load of 748 with the Nosler and Sierra.

Oh hell, 225 gk, tac your in highcotton... Greg or barsness load... Thinkin 49 gr.....

That combo gets 2442fps in my 22" barrel and better than MOA accuracy. I like it!

Thanks, Dinny

I used 47 grains of H4895 for 2245fps out of my blr . It was dirt on deer and hogs.

With the 225 Sierra I've been over 2300fps with AA2015 in a 21" bbl with decent accuracy & there seems to be a tad more room to increase, but it may have plateaued. At 41gr. case base expansion is at .0008" over new brass. I am working upwards toward max with the next range trip, maybe Wed. I'm using Lapua 308 brass necked up & WLR with the bullet about .015" off touching the lands.

I used to use 748 & was very happy with it until I got a chronograph. The deer never knew the difference at woods ranges either.

Going to try some TAC next time I buy powder if it's in stock.

While I load the 225gr. Sierra Game King in .35 Whelen, extensive accuracy testing has found IMR 4064 to produce the best accuracy in my rifle. IMR 3031 produced outstanding accuracy with Hornady Inter-lok 200gr. RN bullets in my Whelen, don't see why it wouldn't do the same in .358 it's worth a try.

Dinny got me to try that TAC after not quite seeing velocity numbers where I wanted them using 4064/4320 powders.

Started about 45g and worked to 50g. In my RAR 46.5 was pretty good and 49 was pretty good. Loaded all around each in tenths and decided upon the 49 number.

My 20” Bbl is over 2450 FPS and sub MOA. HAPPY CAMPER HERE!

CW

I have used 4064 then Varget for years and have too much of either to change. It works in all the .308 cased caliber. Be Well, Rustyzipper.

Here are a few published loads I downloaded off LoadData.com, all for the 225 SGK. These are all max charges - work up, etc. etc.:

49/Varget for 2451'
51/BL-C(2) for2431'
46/H-335 for 2390'
46.5/H-4895 for 2422'
48/AAC-2520 for 2462'
49/TAC for 2552' (this one uses a magnum primer, Fed 215)

That last one is a real winner, I believe it is one that Mule Deer developed for us.
Good luck and let us know what you learn in your workups.
Cheers,
Rex

Check the Sierra app. It’s free to download.

Tannhauser, are those starting loads in the screenshot you posted? I ma perplexed at the disparity between the 44.4 gr Varget in your screens shot versus the 49 gr Varget in the download from LoadData I posted above.
Thanks,
Rex

Yes, starting minimum. Max listed for Varget is 49.0 gr.

Yeah those are minimums. If you look at the bottom of the pic, there is a slider to change velocity; the load data changes as you slide that around. Max load for Varget is shown as 49.0gr, and 48.0gr for 4064, both at the same 2400 fps.