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Interesting pressure situation

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Tenntrapper

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Loading the 150g Nosler CTBST, using H380 powder. All the data I can find says...41.5g min to 45.5g max.
I started at 43g. Only sign of pressure was a little mark on the brass (ejector mark) I guess that's what you would call it, it's a Mauser action and the mark was from where a cut is in the bolt face. Anyway, surely not hitting pressure this low, so...I proceed. At 44.5, I stop. Nothing has changed, no other marks on brass or otherwise signs of over pressure. The original mark hasn't gotten worse.... stayed the same. At this point, I'm not shooting groups, was just doing ladder test... checking for pressure. I did load up a bunch for testing, but hadn't gotten around to shooting them yet.

That was the other day. Yesterday, I talked to Jerry about something else. Oh yeah...can you check something else for me? Feeling 100 percent confident that the data was correct...it came from Nosler, and was verified through a couple other sources...but that little mark was in the back of my mind.

He already had my data in his computer, and as soon as I told him 44.5g, he said...that's too much. It was so quick, I got the impression he hadn't even had time to plug that combo in. 68k psi....I was way over (61k max), and wasn't even to book Max?
Everything else I've tried in this rifle has gone smoothly....all the way to max without pressure. Generous chamber, generous throat, etc. Ended up having to go back to 41.3 to be under pressure and at a predicted node. So, what's the deal with this powder? And how was i so far over pressure and only getting a very faint little mark? Primers fine, etc.
My question about "this powder" pertains to hitting pressure well before book Max...from several books. What about people loading this load without help from Jerry and all his experience, testing equipment, etc?
Something just seems off.
 
Cartridge?


I don't have much experience with ball powders because from what I've seen they can get real weird real quick.
 

Hodgdon H380

I have a thread seeking input on everyones favorite powder to use in the 7mm-08 remington with 150 grain bullets. In looking further into this adventure I see that Nosler lists H380 as the most accurate powder they tested with their 150 grain bullets in that cartridge. With all of the ne...
www.24hourcampfire.com www.24hourcampfire.com



150 etip quick load data on page 2 pretty much matches what you're seeing


I'd find another powder, but I have zero use for ball powder in centerfire rifles.
 
Many factors to consider, that is why they have such a decent variance in the data. If you already started seeing pressure signs at 43g, you should have stopped and reassessed the load variables. Bullet and powder mfgs use modern test equipment with a certain receiver and barrel length, when we load for our rifles we have to take into account the age, throat, chamber measurements etc to make sure we stay on the safer side of things. I rarely, if ever, load max charges, most of my nodes are somewhere close the middle, and I don't worry about chasing a few extra FPS. Of course, I just hunt and don't compete so not trying to cloverleaf all my groups, 1" groups work well for me so if a middle of data node gives me that consistently, I stay there.
 
Remi said:

Hodgdon H380

I have a thread seeking input on everyones favorite powder to use in the 7mm-08 remington with 150 grain bullets. In looking further into this adventure I see that Nosler lists H380 as the most accurate powder they tested with their 150 grain bullets in that cartridge. With all of the ne...
www.24hourcampfire.com www.24hourcampfire.com



150 etip quick load data on page 2 pretty much matches what you're seeing


I'd find another powder, but I have zero use for ball powder in centerfire rifles.
Click to expand...
I wasn't sure that what I was seeing was "pressure". It's a new rifle, and the mark was so faint, I wasn't sure if normal.

It just struck me odd, that such a low powder charge would show pressure so soon. But...why does the computer software immediately show that amount is way over?
I generally don't use ball powder, but like in your link... nosler shows best accuracy, and my local gun store had some in stock...so I tried it.
 
Omega said:
Many factors to consider, that is why they have such a decent variance in the data. If you already started seeing pressure signs at 43g, you should have stopped and reassessed the load variables. Bullet and powder mfgs use modern test equipment with a certain receiver and barrel length, when we load for our rifles we have to take into account the age, throat, chamber measurements etc to make sure we stay on the safer side of things. I rarely, if ever, load max charges, most of my nodes are somewhere close the middle, and I don't worry about chasing a few extra FPS. Of course, I just hunt and don't compete so not trying to cloverleaf all my groups, 1" groups work well for me so if a middle of data node gives me that consistently, I stay there.
Click to expand...
I agree, I don't like running max loads...and usually don't. Several sources said I wasn't at max... especially with the first load. The "indication" didn't change. That faint mark was there from the beginning. Didn't get any worse, and nothing else showed up.

According to Jerry's computer program, I was likely over where I started. 43.6g was 64k psi.
Had to drop back to 41.5g is 54.7k psi.
 
I've read quite a few places, even on the Nosler forum, that Nosler's accuracy load is the lowest es/sd, not actual accuracy.


I tried imr4350 behind a 160 Speer in my 708, started upper mid range and had issues immediately. I had to drop back a bit, found nice accuracy and then went away from the 160 idea all together as the only benefit over a 120-140gr bullet was a little more recoil.


If it shoots good where it is then it is what it is. At the ranges I shoot deer 100-200fps means absolutely nothing in performance in reality.
 
Tenntrapper said:
I agree, I don't like running max loads...and usually don't. Several sources said I wasn't at max... especially with the first load. The "indication" didn't change. That faint mark was there from the beginning. Didn't get any worse, and nothing else showed up.

According to Jerry's computer program, I was likely over where I started. 43.6g was 64k psi.
Had to drop back to 41.5g is 54.7k psi.
Click to expand...
Quickload I take it? I downloaded Gordons Reloading Tool, which is by all accounts just as good as Quickload, but free, I just don't need the data to spend that much on it. Gordon passed away but a group has taken on the project and continuing data for new rounds. Anyway, I haven't played with it, or Quickload data, I normally just stick with published data and start low and look for pressure signs and an accurate load going relatively fast. enough to mushroom my bullet on the target. I downloaded GRT when I got into 277 WLV, which had very little data, but the group quickly developed loads and some members have Quickload so I ended up not needing it for that either.
 
And the reason I don't think a few hundred fps matters….


Old 140gr Nosler ballistic tip in 100 packs. Supposedly they are bombs that detonate if they touch a spider web


7-30 waters with 33grs of 3031- 2300ish fps on a big doe at 30yds. Broke both shoulder, spine and exited, she ran zero feet. Not much of a test, but still a test


708 Remington with 25grs of imr4198, 2400fps-ish, maybe, and the 140's on the largest boar I've ever killed. I'm not sure what he weighed but it took 3 of us to load him on the hitch haul


80-90yds quartered to me. I hit him between the right ear and eye, through the skull, through the spine, through the shoulder and out through the Kevlar impenetrable shield, lol. He ran zero feet.



It's only a sample of two with the 7mm but I've also done the same thing with the 30-06. Reduced velocity 150's, 2500-2600fps or so resulted in very short trips for deer I've shot with it.
 
Remi said:
And the reason I don't think a few hundred fps matters….


Old 140gr Nosler ballistic tip in 100 packs. Supposedly they are bombs that detonate if they touch a spider web


7-30 waters with 33grs of 3031- 2300ish fps on a big doe at 30yds. Broke both shoulder, spine and exited, she ran zero feet. Not much of a test, but still a test


708 Remington with 25grs of imr4198, 2400fps-ish, maybe, and the 140's on the largest boar I've ever killed. I'm not sure what he weighed but it took 3 of us to load him on the hitch haul


80-90yds quartered to me. I hit him between the right ear and eye, through the skull, through the spine, through the shoulder and out through the Kevlar impenetrable shield, lol. He ran zero feet.



It's only a sample of two with the 7mm but I've also done the same thing with the 30-06. Reduced velocity 150's, 2500-2600fps or so resulted in very short trips for deer I've shot with it.
Click to expand...
I agree with this 100 percent. You can slow down most of the "bombs" and make dang good deer killers out of them. Been loading that way for years.
That said...this is a 16.5" barrel. Based on quick loads, mid 2400 fps is about the best I'm going to get with anything heavier than a 120.
 

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