215 Berger 300WSM

[RMagee]

Can the 215 Hybrid be used in a 300WSM at magazine length with and extended box (Wyatt 2.995)?

 

[wboggs]

I believe that will be too short. Most loads using the Berger 215 and 230 are a lot longer than that. Steve Blair has a wealth of experience with the WSM and heavy Bergers. He is always happy to answer your questions and you can depend on his answers.
Bill Boggs

 

[Steve Blair]

You can shoot them at that length but the bearing surface will be well below the neck-shoulder junction. In order to ensure that there is no problem in that area, the COAL should be ~3.150" or longer.

 

[RMagee]

You can shoot them at that length but the bearing surface will be well below the neck-shoulder junction. In order to ensure that there is no problem in that area, the COAL should be ~3.150" or longer.

Got my rifle set up and the bullets in. With the SAMMI .188 freebore I'm touching the lands at 3.022", so 30 thou jump would put me at magazine length. My question is about seating below the neck/shoulder junction. What effect does this have other than burning up case capacity? I've never run into the doughnut with the 300wsm, but have a K&M cutter to remove it should it form. Are there other concerns about seating below the junction?

 

[Steve Blair]

There could be increased pressure from deeper seating but partially offset by a larger jump. My only concern is to stay clear of the neck-shoulder junction as I do not like inside reaming. If you remove any ridge or doughnut from the case, seating depper should work fine when your load is developed at that depth. Seated at 2.992" COAL, the rear bearing surface edge is ~.125" below the neck shoulder junction.

 

[RMagee]

Well my first outing with it produced some surprising results. Surprising to me anyway. 63 grains of RL17 with the 215 Berger seated just over mag length, so a .015" jump, produced an average velocity of 2953fps with a SD of 4. This is in a 26" Kreiger 1-10 twist 5R barrel with a muzzle break. Rifle was chambered by Longrifles Inc with a 300WSM match reamer .335" neck. Necks were turned for about 1.5 thousandths clearance. Going to point the Bergers, sort them and try the load at distance now. This isn't a comp gun, just punching paper, banging steel, and eradicating predators Don't know what the BC is on a pointed 215 Hybrid but at 2950 it should be a wind cheating devil.

I was surprised by the velocity I got. It is a stiff load but bolt lift wasn't sticky. I shot my Grendel over the chronograph to compare and it seemed reasonable. The Grendel was actually a little slower than I thought it would be so it seems velocities were accurate with the chronograph.

 

[Steve Blair]

Be careful with temperatures and Reloder 17. It has a fat area under the pressure curve, which it why it delivers high velocity. It also means that when pressures are too high, it can go from Ok to blowing primer pockets very suddenly.

 

[RMagee]

Yeah we only get colder in Alaska than it is now 8) Actually we may see 15 to 20 degrees warmer tops than what it was today. I'll keep a close eye on it. This was Norma brass. Hope it lasts a while even with a stiff load cause it's spendy.

 

[RossL]

Unless the 215 has a much different shape you should be able to seat the bullet to fit the magazine. I loaded the 230 Berger target hybrid in my friend's Browning A-bolt with a 2.8" magazine it feeds and shoots fine.

Used RL-17 for velocity of 2720 fps. This is with the shorter barreled A-bolt with BOSS.

 

[RMagee]

I know it can be done but I'm looking for best accuracy, velocity. I'd be jumping close to .030" and taking up more powder space. I dare say on the cartridge you show that the ogive is seating into the neck........

 

[RossL]

The bullet IS close to the ogive meeting the neck but this hunting rifle shoots nice clusters at 100 yds consistently and feeds fine from the magazine. I also thought 2700 fps was pretty awesome from a 22" barrel. The cow elk shot behind the shoulders by my 85 yr old friend last fall at 300 yds stopped and fell over dead in just a few seconds. What more could a hunter want?

Get the Wyatt's mag box, seat the bullet to fit and report back on your rifle's performance. I would love to hear your results.

 

[RMagee]

Have the Wyatt box. The loads above were just a tad over mag length so I will be trying some loads at mag length. Performance should be similar, goal is around 2900 at mag length if I can get the same accuracy.