28 Nosler, 150 Grain TTSX

[28gaugewaterswatter]

I am trying to come up with a load for my 28 Nosler, Christensen Ridgeline with 26 inch barrel.
I am using 150 Grain TTSX bullets, CA resident so non lead is required but I also really like the termninal ballistics of the bullet.
Currently using H1000 powder as I had it available at my local shop.
2.83 inches base to OGIVE, 50 thousands from the lands, the gun has a long throat.
I shot a ladder test and found nodes around 79.3 and 80.2 grains. I went with the lower charge to hopefully preserve barrel life as best as possible.
I loaded up 4 round groups of 79.3, 79.4 and 79.2 and shot them round robin, 79.3 had the best es and standard deviation at 6.85 with an average of around 3180.
I loaded up a few more and shot them a few days later,similar weather and conditions. My average velocity jumped up to 3220 and my STD went to 12.52, with an es of 34. including a cold bore shot.
I was double measuring all my loads, so i do not think that I had a change in my powder load.
I have cleaned the bore out after every shooting session and shot a few foulers before each testing session.
I remeasured the bore depth, and found that it is now 12 thousands deeper than I had initially measured, I am not planning on chasing the lands unless necessary.
What am I doing wrong here? Any suggestions on powder change.

 

[Slimfinn]

Were you using virgin or once fired brass?

 

[28gaugewaterswatter]

virgin nosler brass, all inspected and cleaned up before loading if necessary

 

[Yoteklr]

I am trying to come up with a load for my 28 Nosler, Christensen Ridgeline with 26 inch barrel.
I am using 150 Grain TTSX bullets, CA resident so non lead is required but I also really like the termninal ballistics of the bullet.
Currently using H1000 powder as I had it available at my local shop.
2.83 inches base to OGIVE, 50 thousands from the lands, the gun has a long throat.
I shot a ladder test and found nodes around 79.3 and 80.2 grains. I went with the lower charge to hopefully preserve barrel life as best as possible.
I loaded up 4 round groups of 79.3, 79.4 and 79.2 and shot them round robin, 79.3 had the best es and standard deviation at 6.85 with an average of around 3180.
I loaded up a few more and shot them a few days later,similar weather and conditions. My average velocity jumped up to 3220 and my STD went to 12.52, with an es of 34. including a cold bore shot.
I was double measuring all my loads, so i do not think that I had a change in my powder load.
I have cleaned the bore out after every shooting session and shot a few foulers before each testing session.
I remeasured the bore depth, and found that it is now 12 thousands deeper than I had initially measured, I am not planning on chasing the lands unless necessary.
What am I doing wrong here? Any suggestions on powder change.

Was this rifle brand new when you first got the initial BTO measurement? The lands and (thus measurement) will increase fast at first then stabilize at a slower rate of erosion for the next few hundred rounds.
H1000 is going to be the best powder for low bore temperatures. Make absolutely sure you are letting the barrel cool between shots!!! All of my Noslers ( 26,27,28,30) only see cold bore shots...never even three shot strings.
My first 28N lasted for 800 rounds shooting 175gr Elite Hunters with Reloder33 which burns quite a bit hotter thsn H1000. It still shot under one moa but I didn't want to take chance on an errant shot on big game when it counts.
I consider the first barrel i have chambered in a "new to me" cartridge a learning experience. The new 28 Nosler barrel shoots the exact same load.

group shot at 200 yards from a bull bag

 

[28gaugewaterswatter]

Was this rifle brand new when you first got the initial BTO measurement? The lands and (thus measurement) will increase fast at first then stabilize at a slower rate of erosion for the next few hundred rounds.
H1000 is going to be the best powder for low bore temperatures. Make absolutely sure you are letting the barrel cool between shots!!! All of my Noslers ( 26,27,28,30) only see cold bore shots...never even three shot strings.
My first 28N lasted for 800 rounds shooting 175gr Elite Hunters with Reloder33 which burns quite a bit hotter thsn H1000. It still shot under one moa but I didn't want to take chance on an errant shot on big game when it counts.
I consider the first barrel i have chambered in a "new to me" cartridge a learning experience. The new 28 Nosler barrel shoots the exact same load.

group shot at 200 yards from a bull bag
View attachment 27484

It was not brand new, was from the consignment shelf from a shop I would consider family. The previous owner said it had about 50 rounds down the tube. I have been trying to take at least 2 mins between shots to allow cooling

 

[28gaugewaterswatter]

Reshot this mornin. 100 yards. 5-7 minutes in the shade between rounds. ES was 31.5 with a STD of 12.2 on velocities. I had one more node i wamted to investigate, but if that doesnt yield better numbers then what?
Is this worth working off of and tightening or should i go with a powder change.

 

[Firebird24]

Can’t hurt to try a different powder. I have really liked us869 in mine but I also prefer 175 gr bullets. That would be my other suggestion is to try a heavier/longer bullet and see how your rifle responds.

 

[Yoteklr]

View attachment 27554
Reshot this mornin. 100 yards. 5-7 minutes in the shade between rounds. ES was 31.5 with a STD of 12.2 on velocities. I had one more node i wamted to investigate, but if that doesnt yield better numbers then what?
Is this worth working off of and tightening or should i go with a powder change.

I really didn't want to go this way, but I had a Ridgeline. Right out of the gate it would not chamber virgin Lapua brass ( the neck was too tight), when i called to tell them about it they said i voided the warranty by reloading.
The recoil pad was different than advertised.
The action was so hard to cycle that I had to buy an oversized bolt handle. Anyway, I just couldn't get it to shoot anywhere near 1.5 moa. I bedded the action, bedded the scope base, lapped my rings, tried different scopes ( Zeiss v6 5-30, nightforce nx8 4-32). Installed a trigger tech diamond trigger.

The worst factory rife purchase ever. I spent over 500 rounds of components and multiple dozens of hours trying multiple bullets, bullet weights, multiple powders, different primers, seating depths.

Today the only thing left is the action and bolt. Put it in an HS precision stock and a Pacnor SS barrel. Now it shoots.

 

[salmonchaser]

I also owned a Christensen, two of them actually. My 1968 Ruger mdl 77 and my #1s out shot both of the Christensen.
I would want to know how much your brass may be expanding, Haven’t had my first cup of coffee yet so I can’t come up with the numbers, but the shoulders of my 300 HH grow significantly with new brass. Guess I wouldn’t expect too much on a Nosler case given it head spaces on the shoulder.
I wouldn’t worry about your numbers unless you’re going to shoot out past 600. I would be interested if you can tie the high low shots to high low velocity, but I wouldn’t expect it with a 30 ES.
I think I would try shortening up a little.
I use to see groups like that with several rifles. Found an eye doctor who was able to correct my astigmatism such I was looking at the cross hairs consistently. My problem had to do with eye fatigue.
I definitely need a cup of coffee, it’s almost ready.

 

[28gaugewaterswatter]

I also owned a Christensen, two of them actually. My 1968 Ruger mdl 77 and my #1s out shot both of the Christensen.
I would want to know how much your brass may be expanding, Haven’t had my first cup of coffee yet so I can’t come up with the numbers, but the shoulders of my 300 HH grow significantly with new brass. Guess I wouldn’t expect too much on a Nosler case given it head spaces on the shoulder.
I wouldn’t worry about your numbers unless you’re going to shoot out past 600. I would be interested if you can tie the high low shots to high low velocity, but I wouldn’t expect it with a 30 ES.
I think I would try shortening up a little.
I use to see groups like that with several rifles. Found an eye doctor who was able to correct my astigmatism such I was looking at the cross hairs consistently. My problem had to do with eye fatigue.
I definitely need a cup of coffee, it’s almost ready.

I was going to try a few at a deeper seat and see, if it tightens up i will be happy with it. from other sources I have figured out that chasing es and sd without an ultra precision scale is pointless, and the way the rifle shoots is adequate for my max ethical range on game.
I plan on running down the seating depth and seeing if it improves or gets worse.
Might develop an out of state load with a Berger EH 175

 

[RL338]

I was going to try a few at a deeper seat and see, if it tightens up i will be happy with it. from other sources I have figured out that chasing es and sd without an ultra precision scale is pointless, and the way the rifle shoots is adequate for my max ethical range on game.
I plan on running down the seating depth and seeing if it improves or gets worse.
Might develop an out of state load with a Berger EH 175

How are you weighing your charges , that may shed some light on your high ES?

 

[28gaugewaterswatter]

How are you weighing your charges , that may shed some light on your high ES?

I borrowed a lab grade from my friend and shot again, stayed about the same es/sd and group size and position was similar. Seated 15 thou deeper on a whim and my es/sd reduced, but group size again was similar