Loading for .300WSM

Biathlonjimmy

Well-Known Member
Afternoon All,

Sitting in my local RFD is a Tikka T3X Varmint Stainless (L/H) chambered in .300WSM. It only took 4 months to come and my RFD honoured the original price, since ordering prices have increased 10%. :D

I'm looking for some advice with regards to successful bullet/powder combinations for different loads in the above. I have in stock 165gr Interbonds, 208gr Amax and Sako 123gr. If there is a better bullet available then I don't mind changing from the aforementioned. I think the 123gr will be a non starter but willing to listen to your experiences.


Use will be Deer, Pigs & Goats plus informal mid-long range target shooting. I have been loading for .308 & .22-250 for a few years now but never for this cartridge. are there any different approaches that should be taken?


Best,

J
 
I have loaded for the 300 WSM and found it to be pretty happy with a range of bullet weights, and not difficult to load for. That said, it is good to be aware that the cartridge was designed to operate at a significantly higher pressure than other "high powered" rifle cardridges like the 300WM, 308, 30-06 etc. As a fat cartridge, it also has a big shoulder, the higher pressure and wide shoulder can make it less optimal for neck sizing, especially with full power loads...so full length sizing, or neck szing plus bumping the shoulder back can be a good idea, especially if you run at or near full power loads.

A lot of people say it can't do the 200 grain and heavier bullets very well, but they have probably never tried...yes the bullet sticks a long way into the case, but the performance is still good with a fair number of guys running the 200 accubonds for Rocky Mountain Elk with good velocity and performance (usually using RL17). The cartridge was designed around H4350 burn rate. The Powder that was "optimised" for the 300wsm and cartridges like it is Reloder 17. RL17 will often deliver up to 100 FPS increase in velocity without exceeding pressure, however, accuracy nodes can tend to be a bit narrower. I have used a lot of IMR 4831 with good success, good accuracy and velocity in 180 partitions just over 3000 FPS doing 1 inch groups at 100 yds.

If the 165 interbond shoots well it should cover all the mentioned game with aplomb. If you can get a 208 amax load working for you, it would probably be impressive for long range target work, many also use for hunting, but it can make a big mess especially on closer shots.

I have grown to love the 300 WSM, think it's a brilliant cartridge. Compact, super efficient, plenty of power, reasonable recoil, flat shooting & hard hitting...all in a short action without needing an extra long barrel to perform well...what's not to like.
 
Hi J,

I've got a 300wsm and bloody love it !

Its my go to stalking rifle and is also not too shabby at knocking down plates,etc.
Mine is a Blaser R93 and it loves Berger 155grn VLD in front of 67.5grns of Vit160...never chrono'd it so don't know what its doing fps wise, but Reds tend to drop on the spot and its not too bad damage wise on Roe either.

If I do my bit it's capable of shooting 3 shot groups in the 0.10 moa....but being a lightweight rifle you feel it a bit after a long range session...apart from that its great.

Regards,Rob.
 
I've had a .300 wsm Tikka for the last 10 years.
They're superbly accurate with mine still doing .5 moa after well over 1500 rounds.

My standard two loads for it are 168 gr Barnes TSX's and 165gr Sierra Game Kings both over H4350.

I will soon be ordering another one as replacement.
 
Really interested in this thread keen to start reloading again and good to see what you guys are getting on well with.

Deeredriver what powder weight are you using?
 
The .300 Win Mag was originally loaded to higher pressure than it is today in factory ammunition.
If you load the .300 WM to the same pressure as the .300 WSM, you will get 100 to 200 fps more velocity, depending on the bullet and rifles.
SAAMI maximums are 64,000 PSI for the .300 WM and 65,000 for the .300 WSM.
http://www.lasc.us/SAAMIMaxPressure.htm
 
Really interested in this thread keen to start reloading again and good to see what you guys are getting on well with.

Deeredriver what powder weight are you using?

I started of at 67.2gr for both bullets, but have now increased it slightly to make up for the throat erosion.
 
Thank you all for taking the time to respond in such detail. :tiphat:

I picked up my rifle before Christmas but due to a family skiing holiday I have only just started the process. I measured the magazine and also c o l to the lands before loading. The mag will take upto 2.875 in and with a 165gr interbond touching the lands the c o l would be 2.870. I decided to use hornady superformance and rem 9 1/2 magnum primers. I uniformed the brass as it's Winchester then loaded 6 x 3 rounds starting at 69gr working in .5gr to 71.5gr with 72gr being book max. I seated the interbond to give a c o l of 2.860 as per the manual.

I'll fire them today and report back.

Lastly a few pointers for those that want to reload for the. 300wsm, aka things I failed to prepare for:

1: When you buy new shell holders, don't forget one for the auto prime. Lucking I could prime from the press albeit a tedious process.

2: The lee powder funnel .22-45cal does not work with the .300wsm. My hipflask funnel did ok though.

3: Lastly, and most bloody obvious, don't forget to buy suitable ammunition boxes. Individual Food bags are not a good substitute.

Best,

J
 
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hi J
am also a convert, picked up one in Sako75 two years ago, I took it for a walk in SA last year; performaed fantastically on everything big and small.

my data:
CCI Magnum, Hornaday Interbond 165grn, 67.5grn of H4350, CBTO 3230

Mark
 
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