300 RUM, 230 Berger Hybrid, Retumbo Max Load?

[cohunter14]

I am just curious to see what everyone out there has gotten as a max working load for the 230 Berger Hybrid in the 300 RUM using Retumbo. I worked up a ladder from 87 grains to 92 grains in 1/2 grain increments recently and got to 92 grains with no real pressure signs at all. I have checked the primer pockets as well and they seem fine. I am only getting 2,960fps at 92 grains, which makes me feel like I have some room, but I wanted to make sure. HSM's 230 Hybrid loads show 3,000fps and I have heard of a ton of people getting 3,000+, which is why I think I might have some room. Am I okay to work up towards 93 or 94 grains? This is at 3.60 COAL by the way. Might go longer eventually, but want to start at magazine length and see what I can get.

What's strange is that I worked up loads with this same rifle for the 200 grain Accubond and I was getting some pressure signs at 94 grains of Retumbo, so I am somewhat surprised I haven't gotten any yet with the 230's.

Any thoughts are appreciated!

 

[rooster740]

I have a Remington sendero and have the exact findings. My coal is 3.9 and right at your velocity findings. I could go hotter then 92 grains with retumbo, but started to loosen primers with Remington brass.
With the 200AB I had better luck with RL25 at right around 3200fps.

 

[cohunter14]

Thanks for the info! How high were you able to go until significant pressure signs showed up?

Anyone else with thoughts?

 

[Lefty7mmstw]

Anyone else with thoughts?

retumbo is a bit slower with a 225-230 than either rl33 or rl50. You can easily get 3,000 fps with either of those, and possibly a bit higher without pressure signs or loose primers.

 

[cohunter14]

Yeah, I am still up in the air with RL33. From the sounds of it, you need to be loading out into the lands and it also sounds like it might be a little temp instable.

 

[Lefty7mmstw]

Yeah, I am still up in the air with RL33. From the sounds of it, you need to be loading out into the lands and it also sounds like it might be a little temp instable.

I'm loading the 225 hdy to mag length and it shoots .6 moa in a lh bdl without a brake.... 3,000 fps with 95 rl33 lit with a 215 in rp brass....

the 220 nos hpbt seems to like 102 rl50 with the same powder and primer... the hdy also liked rl50 but the compression was a bit up on that load so I went to rl33

 

[cmorsch]

Im getting 2965 with 89.4 gr of retumbo in my 300 RUM with the 230 berger hybrids.

 

[cohunter14]

So has anyone jumped up over 92 grains before?

 

[ajridgedell]

Little old, but working up load with 230 hybrids today, went from 87 to 93 in one grain increments and could see slight ejector circle at 93 going 3055fps from 26" sendero. I Might start a new thread with my load work up and results

 

[cohunter14]

Good info! I ended up working up to 94 grains where I finally got a heavier bolt lift and 3,037fps.