New 300 Win Mag with 215 Bergers

[mpayne]

My HMR 300win likes 78.5 of H1000 with the 212 ELD-X average 2965fps

 

[Korhil78]

I just finished up a load for my 300 win mag. Ended up with 76.3 gr of H1000 with the 215 gr berger. Avg speed was 2905 fps. The load was 75.5 gr of H1000 at the same speed but I had a different firing pin and firing pin spring put in as well as having it bushed. I lost about 50 fps and had to up the powder charge to get it back to the 2900 fps range and the accuracy came back. I will be testing it out to 1000 yards this Saturday.

I will also note that I started at 73 gr and worked up like others did.

 

[kfreeze]

73.0 grains it is. I know H1000 is kinda the go to powder with 215's. Any great success with another powder?

I like rl 26 in mine with 190 nosler ablr bullets. With the same bullet and h1000, I was crunching powder hard and still no pressure signs at mag length.

 

[lancetkenyon]

As long as you're throwing a bunch of unlikely things, lets add a bad scale, bad calipers, or mislabeled powder.
Assuming the OP is using virgin brass, it'll be 2-3 firings before it's fully chamber sized. Hard to get over pressure when brass is heavily undersized.
I'll agree with brass manufacturer case volumes, so let me update my previous comment. Start at 75gr if your using adg, rws, or any other smaller case volume brass.
Starting at 73 gr will waste brass, powder, primers, bullets, and barrel life.
Just my opinion.

So, you have never had a tight bore? I have. And it made a HUGE difference in pressure.
Just an example.
I have loaded for 19 different 28 Noslers.
I always start at 83.0gr RL33. In 17 of the 19, the sweet spot was between 86.0 to 89.0 @ 3080-3160 w. 195s. And out of those 17, all maxed out between 88.0 to 89.0gr.
But two had tight bores. Same lots of powder, same lots of bullets, same lot of primers, brass was same manufacturer and weights. The first one I started at 83.0, and got slight pressure signs and 3160fps with the first shot and had to go back and pull a bunch apart. A full 3-6 gr LOWER than normal. Final load was 82.4gr @ 3110fps. The other ended up max load at 83.2gr @ 3130fps.

So you should start lower than 2 gr of where you think max will be.

As for .300WM, only loaded for 8 of them so far. All using either a 210 HVLD or 215 Hyb. All ended up between 74.5 to 77.0gr of H1000. 76.0 to 77.0gr has almost always been max load.

 

[thatguyshm]

My Christensen Arms Classic is a 30-06, and I get above book max velocity with several grains less than book max charges. 180gr ammo advertised in the 2740 range gets me almost 2900 fps. Start low and build up to your rifles max.

My hunting load is a 180gr Accubond with 59.0gr of RL22 in nosler cases . At 60 degrees, I get 2850 fps, but the Nosler book with the same load data says I should be in the 2670 range. Account for lot variance and I'm still shooting fast.

Be safe and smart.
SHM

 

[DF7753]

73.0 grains it is. I know H1000 is kinda the go to powder with 215's. Any great success with another powder?

I use IMR 7828 behind 210 VLD with very good results.
Don

 

[mmw194287]

74.5 grains for me--averaging 2965 with 215s.

 

[brentc]

Lance nailed it. Lot to lot H1000 can be huge differences. As Lance said the brass capacity varies greatly as well(89-95 gr H20). Start around 73 and work up.

I just went through a lot difference with H1000 on my freshly opened 8 lb jug. I had to reduce by 1% to get back into the node and to keep pressure in check. It wasn't a huge difference, but it was enough to push me over the pressure threshold.

 

[Shane Lindsey]

New Norma brass max was 77gr. That same brass fireformed had to be reduced down to 76gr to be happy happy. Started at 74gr loaded long.

 

[Russ661]

I'm experimenting with seating depth now using 215g hybrids, ADG brass, WLRM primers and 70 grains of H1000. Right now it looks like either .040 or .010 off the lands are the sweet spots. I'll be doing more tests next week. To the OP's question, the safest way is to start low; I have seen pressure signs with 76 grains of H1000 under 212 eld-x bullets in my rifle so I choose to start even lower than most here with the 215 hybrids loaded long.

 

[tlsmith22]

I just built a 300wm with a 26" 9.4 twist Proof barrel and had it chambered with the Rhian Mantha reamer designed to shoot 215 Bergers. I wanted to run VV N570 powder as it has the best velocity I have found for the 215. It meters like crap because the grains are huge but I am getting right at 3100 FPS with the 215. I for sure recommend starting low and working to a max load. If you cant find the VV N570, then the H1000 is the next go to powder with a slight velocity loss of 100-150 FPS.

 

[Double Dropper]

Question, for all you gents running the 215 Burger LOL is your throat standard or SAAMI ? or did you opt for a bit longer throat to run these bullets. I get the feel that the benefits are multiplied if you "long throat" your 300 a bit??

 

[Kevin87]

Worked up a load yesterday--ended up at 77.5g H1000, .020 off the lands, CCI 250 primers. Average was 2953 fps with no pressure signs. Very happy with the Ridgeline so far. Thanks for all the input!

 

[Wolf76]

What a surprise-300 WM ~77grs of H1000 +215 gr berger.

Hope you started at 73 grs

Congrats