300 WSM and 215 Berger?

[bigngreen]

I'm looking for any info on building a 300 WSM to push the 215 Berger, I've built a few 300 Win's set up for the 215 Berger and the performance has been nothing short of spectacular for a long range hunting type rifle, just curious if the WSM can equal the Win?

 

[dkhunt14]

You can get around 2900 with good accuracy with H4831. That all depends upon the barrel. Start low and work up. The WSM should give better accuracy. Easy to tune compared to 300 Win. Matt

 

[wboggs]

To get the most out of the .300WSM with the long Berger 215 you will need to seat the bullets very long and have a long throat. I have experimented with this type setup and it feeds very well from a R700 Ultra Mag. factory magazine. The bullets do not feed properly from the WM. magazine. Nice setup for a hunting rifle and accurate but it is more trouble than a 300WM and can not reach WM velocities with each loaded properly.
Bill

 

[dkhunt14]

The 300 WSM is dominating the 1000 yard BR game. There is many 10 shot groups in the 4 and 5 inch range. The 300 Win disappeared and for good reason. It wouldn't shoot as good and was a lot harder to tune. I will take the 100 fps loss to have the accuracy. I build all my hunting guns on single shot Bat M's so have plenty of room and throat .210 length. I would throat out a little more for the 215. The 215 Berger is a good bullet and so is the 210 VLD hunting. Matt

 

[sbhooper]

How about IMR 7828 in that heavy of a load?

 

[dkhunt14]

That would probably work. In benchrest I like powders that burn clean and top velocity isn't a requirement. Another good thing about the 300 WSM is the throat hardly moves in a season; like about 2 to 3 thousandths. When I shot the bigger magnum type cases like the 300 win and 300 Weatherby the throat would move up to 15 thous. every other match. Matt

 

[bigngreen]

Thanks for the information, so it looks like about 100 fps loss over the 300 Win would be what I'm looking at with both properly built, I usually get right around 3000 fps with the 300 Win and the 215. I'd likely build a 300 WSM on a long action or a Defiance XM action, in this kind of rifle it is nice if I can feed from the mag since this size case I will use in a rifle around 10 lbs and would get used in the timber as well. All my larger cased 30 cal and all my 338's are single feed but built for strictly shoot from a front rest on the ground at much longer ranges.

 

[wboggs]

Do your calculations properly for throating of a long .300WSM cartridge. Remember the 215 Hybrid (and 230) have a boat tail length of .22" which means you have to seat below the neck shoulder junction in the short .3" neck. Feeding is unreliable with a WM magazine even though it is long enough.

 

[dkhunt14]

It doesn't matter if the boatail is below the junction as long as the pressure ring isn't. The Boatail is around .170 on a 210 VLD. and my pressure ring is about even with the boatail junction with a .200 freebore. Now you might need a little more freebore then a 210. You can move the pressure ring to about the middle of the neck. The WSM isn't like a 300 Win. the throat doesn't hardly move. I've shot it 3 seasons which is about 600 plus rounds and don't move my bullets more then 3 thous. to keep them 10 thous. in. Matt

 

[wboggs]

Excellent feedback from dk. One of the top shooters I know has a .28" freebore on his comp rifle in .300WSM for the 230's. I noted at the recent Berger match that the 7mm's are still doing well.
Bill

 

[Camaro80z]

I just had a 300 wsm built to shoot the 230's. Would love to hear more info on how the 215's and 230's shoot and what loads everyone is using.

 

[dragman]

I am a huge 300WSM fan. I almost only run single shots even in hunting rifles. running 30" barrel and throated right you can get 215's up to 3000+fps with the WSM. I wouldn't run them that hot for target but it can be done safely.
lots of bench records for the WSM can't go back to the WM for me.

 

[wboggs]

What OAL are you running with the bergers seated way out?
Bill

 

[dragman]

3.150 is my dummy round I did end up changing it a little though.

 

[wboggs]

I know a shooter who has one set up for 3.25-3.28" OAL using the heavy Bergers. Shoots like a dream. AS dragman has noted; fast, accurate, decent barrel life, loads are easy to tune, good components.
You can run these through an Ultrmag. magazine in a hunting rifle and have that advantage.
This cartridge is aging well.
Bill

 

[Camaro80z]

My dummy round is 3.225 and I'm running a 27in barrel. What powders are you using?

 

[dragman]

H4350 was one of my go too powders H1000 and some RL powder if your chasing some speed.

 

[wboggs]

H4831SC for matches. Many loads have also been developed with H1000.

 

[ballistic64]

Im having one built right now using an ultramag long action from a sendero. I spec'd a freebore of .225 and planned on shooting 210s. Will this freebore still allow seating 180-190 gr bullets into the lands?

 

[Steve Blair]

Since my .300 WSM is an F-Open rifle, it may not apply to your build. My reamer has a .280" freebore for 230 Hybrids. Best competition results, in a load that I can actually shoot, is with H4831 SC. Best velocity was with IMR 7828 SSC, but it was beyond my ability to manage recoil on the rest. The 7828 load was very accurate and would be a very good choice if not overly concerned with tracking on the rest. [br]
A .180-.200" freebore should be fine for 215 Hybrids. They can be shot in a .280" but it is not optimal.