I got to 88 grains and no pressure signs.

[Toptuna]

I loaded a powder ladder for my 300 rum with Berger 230's. I got no pressure signs with retumbo up to 88 grains. I'm perplexed. This is max load for Berger load data. It's tough to get out and shoot here in San Diego. How high have you guys gone with this same load?

 

[FearNoWind]

What benefit would there by to pushing the load higher? By the time you get to "pressure signs" you're already far beyond the reasonable pressure limits for the rifle.
Pressure signs aren't something we strive for, they're simply indicators during load development that we've already pushed too hard on the limits.

 

[Toptuna]

What benefit would there by to pushing the load higher? By the time you get to "pressure signs" you're already far beyond the reasonable pressure limits for the rifle.

That's not what I've been told. I've been told reach pressure signs(stiff bolt, ect.) and back off a grain.

 

[MagnumManiac]

Well whoever told you that tidbit of info is WRONG!!
Stiff bolt lift has pressures high enough that the steel of the chamber is flexing, hence the case being wedged in the chamber, it has grown LARGER than the chamber.
The very first excessive pressure sign is ejector marks on your case heads, this means brass was able to flow into the recesses of the bolt face, this alone is very high pressure.
I own a Pressure Trace II, in nearly every instance of ejector marks, stiff bolt lift and sticky extraction, pressures have been above 70,000 psi, and above 80,000 psi when ALL 3 indicators were present.

My advice, if you don't want unexpected brass particles entering your face, stick with the published loads, for every grain of powder increase, pressure rises exponentially, velocity DOES NOT.

Cheers.
gun)

 

[Toptuna]

Well whoever told you that tidbit of info is WRONG!!
Stiff bolt lift has pressures high enough that the steel of the chamber is flexing, hence the case being wedged in the chamber, it has grown LARGER than the chamber.
The very first excessive pressure sign is ejector marks on your case heads, this means brass was able to flow into the recesses of the bolt face, this alone is very high pressure.
I own a Pressure Trace II, in nearly every instance of ejector marks, stiff bolt lift and sticky extraction, pressures have been above 70,000 psi, and above 80,000 psi when ALL 3 indicators were present.

My advice, if you don't want unexpected brass particles entering your face, stick with the published loads, for every grain of powder increase, pressure rises exponentially, velocity DOES NOT.

Cheers.
gun)

I did forget to add there were no ejector marks. I had none of the three indicators you mentioned. Thanks for the detailed info.

 

[FearNoWind]

Well whoever told you that tidbit of info is WRONG!!
gun)

My sincere thanks for the support. I cringe every time I read a post by some hotrod who encourages shooters to use the "hard to open bolt" test for testing load pressures. Your post is very much appreciated.

 

[Deleted member 46119]

I did forget to add there were no ejector marks. I had none of the three indicators you mentioned. Thanks for the detailed info.

if you are looking for pure power and wonder what the Darwin awards are, keep going.

if you are looking for you accuracy node, you may have passed it. Just sayin...

 

[brentc]

I loaded a powder ladder for my 300 rum with Berger 230's. I got no pressure signs with retumbo up to 88 grains. I'm perplexed. This is max load for Berger load data. It's tough to get out and shoot here in San Diego. How high have you guys gone with this same load?

Not disagreeing with anyone in this thread. A hard bolt lift is too far, but a slight ejector mark is not. Everyone has their methods for finding what works best. The max load for a rifle during load development is a key piece of information from a ladder test. You can't know where max is for a given rifle if you haven't reached it. Berger is normally very conservative on their load data. If 88.0 is not quite max, load up in half grain increments beyond 88.0 to the very first indication of pressure, which is normally a slight ejector mark, and back down to wherever your most accurate load is below that point. For your combo try a ladder up to 91.0 and be ready to disassemble the loads that are above 89.5. Oh yeah, and don't do this with virgin brass. Virgin brass will not show pressure indicators as soon as fireformed.

 

[Toptuna]

if you are looking for pure power and wonder what the Darwin awards are, keep going.

if you are looking for you accuracy node, you may have passed it. Just sayin...

Save the smart remarks for somone else. I came here asking questions and for some guidance.

Thank you for your second sentence. I may well have passed the node.

 

[Toptuna]

Not disagreeing with anyone in this thread. A hard bolt lift is too far, but a slight ejector mark is not. Everyone has their methods for finding what works best. The max load for a rifle during load development is a key piece of information from a ladder test. You can't know where max is for a given rifle if you haven't reached it. Berger is normally very conservative on their load data. If 88.0 is not quite max, load up in half grain increments beyond 88.0 to the very first indication of pressure, which is normally a slight ejector mark, and back down to wherever your most accurate load is below that point. For your combo try a ladder up to 91.0 and be ready to disassemble the loads that are above 89.5. Oh yeah, and don't do this with virgin brass. Virgin brass will not show pressure indicators as soon as fireformed.

Thank you for awesome advice. This was my intuition and was looking for this bit of advice. I had no ejector marks on 88 grains and max load was 88.2. I did not want to go up to that. I've gotta sit down and rethink all of this ASAP. Thanks again.

 

[Deleted member 46119]

Save the smart remarks for somone else. I came here asking questions and for some guidance.

Thank you for your second sentence. I may well have passed the node.

Sorry, I was trying to make a joke. Wasn't serious. Should have put a smiley there or something.

 

[Deleted member 46119]

Now on a more serious note: What BrentC said.

and

I do exceed 'book' in some of the 300 RUMs I load for but it is with longer COAL than book.

If you give more detailed specifications I will model them in QL.
COAL
H2O capacity
COAL touching the lands
Barrel length

and last

San Louis Obispo is very nice. We have a nice range with targets out to 700. If you can work it out to come here, I will make time with chronographs, pressure trace II and other things that will help. (Yeah, work season is winding down, boo Deer season is over).

 

[Toptuna]

Sorry, I was trying to make a joke. Wasn't serious. Should have put a smiley there or something.

It just seemed like you being an £*^%#. No worries though my friend. Thanks for the help and your time.

 

[Toptuna]

Now on a more serious note: What BrentC said.

and

I do exceed 'book' in some of the 300 RUMs I load for but it is with longer COAL than book.

If you give more detailed specifications I will model them in QL.
COAL
H2O capacity
COAL touching the lands
Barrel length

and last

San Louis Obispo is very nice. We have a nice range with targets out to 700. If you can work it out to come here, I will make time with chronographs, pressure trace II and other things that will help. (Yeah, work season is winding down, boo Deer season is over).

Copy. I have this stuff written down. I will post it up later when I get home. I have the Wyatt magazine box for a longer coal. It's a stiller action/broughton 5c. Thanks again for all the offerings and I hope I can take you up on the offer ASAP.