300 WSM--Need Your Data for Cartridge Guide

[BigBolt]

Folks,

We're starting on a new Cartridge Guide--this one for the 300WSM and 7WSM. If you've seen any of our previous Cartridge Guides, you'll know we try to make them the definitive resource on the web for that particular chambering. It's a format that has been very popular with readers--our .308 Guide has received 195,000 pageviews.

Creating a new Cartridge Guide is a big job--it can easily involve 100+ man-hours of work. So we need your help. Also having proven load data from real shooters benefits everyone who eventually reads the article.

For the 300WSM guide we need shooter input regarding:

1. Favorite Accuracy Loads
2. Favorite Hunting Loads
,for #1 & #2 we need powder, charge weight, bullet, primer, brass mfg., velocity, seating depth or OAL, recommended twist, and one or two sentences commenting about the load. Include your barrel type and twist rate if possible.)

3. Recommended Bullets.
Because the 300WSM caliber is used both for long-range target use and hunting at all distances, we need to cover a wide selection of bullets. We're especially interested in comparisons among the High-BC match bullets, and learning about the real-world performance of hunting bullets of various weights/construction.

4. Reloading Tips.
If you have developed any special loading practices that work real well with the 300WSM or 7mm WSM, let us know. We will also cover the 270WSM necked up to 7mm, as this is used by many long-range shooters. We are very interested in knowing what kind of brass prep you've found to work best, both with Winchester and Norma brass.

5. Die and Tool Recommendations.
We've heard some good things about custom dies from Hornady and Warner Tool, and the Lee Collet dies work well for some guys. Let us know your die preferences and what sizing methods work best.

6. Brass.
We want to hear your experiences using both Winchester and Norma Brass.

7. Gun of the Week.
We're looking for a 300 WSM long-range target rifle to feature.

Shooter's Reference Load Data for .300 WSM (Winchester Short Magnum)

A good place to start

 

[Torbjorn Strom]

300WSM load data.
Reference your request for load data for 300 WSM.
I have been shooting longrange with the 300 wsm for some years, do not hunt with this catridge, so only long range.
Rifle is a Danish Schultz & Larsen DL medium action ( 30-06) fitted in a GRS laminated Sported stock,switch barrel system with a 74cm ( 29" ) heavy bull barrel 1:9 twist rate cut rifled carbon steel barrel. using 300Wm steel mag adjusted lips to achive proper feeding.
1: Accuracy load.
1st load: 67,3 gr Norma MRP, federal 210 LR , Norma brass, 215 gr Berger Hybrid bullet, BTO 62,4 mm = Jump 0,25 mm & Coal of 82,35 mm, redding neck size bushing .336 . 870 m/S at 0 degree C . ES 3 SD 2.
2nd load : 67,3 gr MRP Federal 210 LR , Norma brass 225gr Hornady match bullet, BTO 61,9 mm jump 0,25 mm Coal 81,75 mm, Coal 81.8,mm, neck size .336 , 860 m/s at o degree C ES 3 SD 1,5,
3rd load: 67,6 Norma MRP, Federal 210 LR , Norma Brass , Berger 230 Hybrid bullet, BTO 62,75 mm = Jump 0,25 mm & Coal 82,65mm neck size .336 855m/s at 0 degree C, ES 3 SD 1.5 .
Shooting 8 mm groups att 100 m , 20 mm at 200 m and sub moa groups at 1200 m on steel all being 5 shoot groups. Shooting results have been measured with my Lab Radar Chrono.
Thank you for a very god site and I hope this data is adding something that you can use..

 

[Yote Hunter]

Interesting Seating Depth test in my 300 WSM using Berger 215 gr Hybrids and 64.8 gr RL 23 with CCI BR primers at 502 yards.
Rifle Specs. Kelbly Atlas Tactical action, Bartlein (28”) 1:10 5R and Revolution Style BR stock (3” flat forend) Trigger Tech Trigger (1 lb +/- pull). According to my measurements 0.010” Jump shot 0.05 MOA Scope: Valdada 4.5-30x56 Recon.

 

[quest450]

WOW ! that's impressive at 500yd
I'd love to see a repeat test in 0.001" increments on either side of the 3.249" seating depth from 3.247" to 51"

 

[quest450]

there's nothing wrong with the next two groups up BTW

 

[Torbjorn Strom]

Hi.
That is impressive.Very good.
I am also experiencing good results with 0.010 jump in my 300wsm with 215 hyb bullets.
So one can say that that the 0.010 jump is where the 215 hyb bullet is at home..
Managed to tighten the 100m groups down to a bughole. That was earlier in 2023
Right now I am moving the barrel over to a Tikka T3 action. Going to fit it in a PSE e-tac carbonfiber stock and see how that works out. Will be using a Kahles Ki624 scope with the MSR recticle.