Seating depth testing with lower charge

[Zack_va248]

I loaded up some 6.5 creed developing a load for my 24" bartlein 1:8 Tl3.
Hornady once fired from this chamber and annealed
H4350 @ 40.4g
140g eldm
CCI 200
My question, is it ok to test seating depth with a lower charge? should the findings hold true at increased nodes. I'm seating every .005" starting at .040" jump going to .060"
I loaded these up before doing my ocw test.
I did load up my OCW as well
It'll be every .3g starting at 40.4 and ending at 42.5
I loaded the OCW @ .060" jump

I chose to start the ladder at 40.4 because the guy I bought this BA from sent me his load data and it was 40.4

 

[cruze5]

this is a good page to favorite: http://www.hodgdonreloading.com

starting load says 37.2 grains

 

[Zack_va248]

this is a good page to favorite: http://www.hodgdonreloading.com

starting load says 37.2 grains

I'm familiar with their site. I went with a higher starting load because the guy I bought the rifle from ran this higher charge. 40.4 it seems from looking on here is a low charge weight. most everyone appears to be in the 41-43g range. Regardless I'm just looking to find out if seating depth testing will yeild the same results with a low charge weight or if I should pull those bullets and recharge after my OCW findings?

 

[Dthomas3523]

I loaded up some 6.5 creed developing a load for my 24" bartlein 1:8 Tl3.
Hornady once fired from this chamber and annealed
H4350 @ 40.4g
140g eldm
CCI 200
My question, is it ok to test seating depth with a lower charge? should the findings hold true at increased nodes. I'm seating every .005" starting at .040" jump going to .060"
I loaded these up before doing my ocw test.
I did load up my OCW as well
It'll be every .3g starting at 40.4 and ending at 42.5
I loaded the OCW @ .060" jump

I chose to start the ladder at 40.4 because the guy I bought this BA from sent me his load data and it was 40.4

Depends on how big a difference in charge you’re talking. If it’s within a grain (or even a bit more) it will probably be about the same. As a large change may affect the timing the bullet leaves muzzle a bit more.

Personally, I don’t worry with seating depth until I’ve found my charge weight. That way I don’t have to worry with anything changing.

Though if it’s for prs, it likely won’t change enough to miss a target.

 

[Zack_va248]

Depends on how big a difference in charge you’re talking. If it’s within a grain (or even a bit more) it will probably be about the same. As a large change may affect the timing the bullet leaves muzzle a bit more.

Personally, I don’t worry with seating depth until I’ve found my charge weight. That way I don’t have to worry with anything changing.

Though if it’s for prs, it likely won’t change enough to miss a target.

I'll run my ocw test first then. Probably going to run it at 4- 500 yds. I'm mostly going to pull my information from velocity and choose the middle of the node anyhow and bounce that info with what I see on the targets. If the ocw charge is drastically different than my seating depth charge of 40.4 then I'll pull the bullets, resize the necks, and recharge to ensure I'm not wasting materials and barrel life.

 

[Jabot]

Depends on how big a difference in charge you’re talking. If it’s within a grain (or even a bit more) it will probably be about the same. As a large change may affect the timing the bullet leaves muzzle a bit more.

Personally, I don’t worry with seating depth until I’ve found my charge weight. That way I don’t have to worry with anything changing.

Though if it’s for prs, it likely won’t change enough to miss a target.

What seating depth do u do your charge wieght test at

 

[Jordanwickham]

Obviously don't just take my word for it, work everything up.

If you are going the seating first way I'll just say set it at 41.8 grains. If you are going for velocity charges your going to end up a bit north of that. Wouldn't advise an OCW test at 400 yards. I run them at 100. If you are going for a lower velocity and high precision load you'll probably be right around 41.8.

If it were me I'd do a pressure string first at 30k jump .5 grain increments from that 40 grain start charge and go from there.

 

[Dthomas3523]

What seating depth do u do your charge wieght test at

.020 ish off lands.

I just take a rough measurement to make sure I’m off the lands. Knowing exactly down to a thou doesn’t make a difference.

 

[RaiderPower]

I've been doing some research on this myself. I saw a an article posted on Berger's website that suggested they now recommend using the seating depth testing first and then moving into a ladder. Of course, I can't find a link now that I want to share the article.

Precision Rifle Blog also has a series of articles on this from back in March that reports on some findings primarily from Short Action Customs:

Bullet Jump: Is Less Always Better?

About 2 years ago, Mark Gordon shared some preliminary research he’d conducted with the Applied Bal...

precisionrifleblog.com

I just got some of the 144 gr. 6.5mm Berger's and I think I'm going to try the seating depth testing then move into ladder testing and see what happens for the load development with those bullets.

 

[Jabot]

I tried it seating depth test first, didn't work out for me very well. Got good groups with test till I bought pressure up then it changed where it grouped better at . At low pressure it grouped great at 50 thousandths off, then with pressure it grouped better at 35 thousandths off. Just what I experienced

 

[Jordanwickham]

I tried it seating depth test first, didn't work out for me very well. Got good groups with test till I bought pressure up then it changed where it grouped better at . At low pressure it grouped great at 50 thousandths off, then with pressure it grouped better at 35 thousandths off. Just what I experienced

To do this type of testing you need to know a target area. Like say I want to end up around 42.7 grains I don't do a seating test at 40.4 grains then test up to 43 grains. I would do a seating test at like 42.2 or 42.4, something I knew for sure wouldn't have pressure then start a ladder, OCW, or Saterlee testing from there.

I don't feel that this would be a good way to go for a new barrel, new cartridge, new everything since you don't have with first hand experience where you want to be.
You could do a pressure test at like 20k(ish) off the lands find out where your bust point is and do a seating test around 3/4 of max then start testing for powder. Keep in mind that if you go to 3/4 then end up at like 80k off your bust point from earlier just slid down from Max a bit.

 

[Jabot]

Agrr

To do this type of testing you need to know a target area. Like say I want to end up around 42.7 grains I don't do a seating test at 40.4 grains then test up to 43 grains. I would do a seating test at like 42.2 or 42.4, something I knew for sure wouldn't have pressure then start a ladder, OCW, or Saterlee testing from there.

I don't feel that this would be a good way to go for a new barrel, new cartridge, new everything since you don't have with first hand experience where you want to be.
You could do a pressure test at like 20k(ish) off the lands find out where your bust point is and do a seating test around 3/4 of max then start testing for powder. Keep in mind that if you go to 3/4 then end up at like 80k off your bust point from earlier just slid down from Max a bit.
[/QUOAgreed

 

[DAVETOOLEY]

This process has worked for me for 40+ years. This is predicated on being able to touch the lands. I go to the range with all my loading equipment. My press is C-clamped to my loading bench and at the range it attaches to a bracket that fits in a receiver hitch. I have primed brass, a powder measure with a known starting weight. A starting seating depth that is just touching the lands. Land marks half as long as they are wide. I take my powder of choice and work up a max starting load by increasing the powder charge until I either get hard bolt lift or an ejector pin mark. That establishes my max pressure condition. Max powder with the bullet touching the lands. I start shooting two shot groups at 200 yds. seating deeper in .005" increments. Pressure is dropping as the bullet is seated deeper so at some point vertical can show on the target and that requires more powder to get the pressure back up some and usually takes care of the vertical. I evaluate the groups and look for any seating depths that are worth revisiting. If nothing shows promise I move on to another bullet, new starting seating depth and use the data on powder charge I just established and do the same process over again. Very seldom does it take more than an afternoon of shooting to get a good working load.

 

[Jordanwickham]

Correc

This process has worked for me for 40+ years. This is predicated on being able to touch the lands. I go to the range with all my loading equipment. My press is C-clamped to my loading bench and at the range it attaches to a bracket that fits in a receiver hitch. I have primed brass, a powder measure with a known starting weight. A starting seating depth that is just touching the lands. Land marks half as long as they are wide. I take my powder of choice and work up a max starting load by increasing the powder charge until I either get hard bolt lift or an ejector pin mark. That establishes my max pressure condition. Max powder with the bullet touching the lands. I start shooting two shot groups at 200 yds. seating deeper in .005" increments. Pressure is dropping as the bullet is seated deeper so at some point vertical can show on the target and that requires more powder to get the pressure back up some and usually takes care of the vertical. I evaluate the groups and look for any seating depths that are worth revisiting. If nothing shows promise I move on to another bullet, new starting seating depth and use the data on powder charge I just established and do the same process over again. Very seldom does it take more than an afternoon of shooting to get a good working load.

Correct me if I'm wrong but the pressure drop will happen between off the lands to about 40k showing negligible change but after that the pressure will begin to go up again. Atleast this is my experience which is much less than your experience.
The best way I've found for getting a load for new gun new cartridge is just a typical load development whichever you prefer with seating at the end.
I feel the seating first method is effective for a small change like a different bullet, different lot of powder, or new barrel where you have a baseline to go off of. The only source I've seen calling for this method is guys who have a stack of blanks that they chamber when they need to so there's not really much of an unknown.

 

[DAVETOOLEY]

Correc

Correct me if I'm wrong but the pressure drop will happen between off the lands to about 40k showing negligible change but after that the pressure will begin to go up again. Atleast this is my experience which is much less than your experience.
The best way I've found for getting a load for new gun new cartridge is just a typical load development whichever you prefer with seating at the end.
I feel the seating first method is effective for a small change like a different bullet, different lot of powder, or new barrel where you have a baseline to go off of. The only source I've seen calling for this method is guys who have a stack of blanks that they chamber when they need to so there's not really much of an unknown.

I don't have a number for when the pressure starts to go back up. I'm never jumping the bullet that much unless there is no way to touch the lands.I watch the target. Might be a good question to an ammo maker that does everything in a controlled environment. It's been my experience that a little more pressure will most of the time tune out the vertical. That can be more powder, closer to the lands or more neck tension. The problem comes when the rifle you're shooting isn't accurate enough to see subtle changes on the target. Hunting rifles take larger adjustments to see and precision target rifles will shoot differently with minute changes. It's all relative to the accuracy potential of the platform.

 

[Off Duty Ninja]

Just load and shoot and experiment. Welcome to the fun filled world of reloading where you'll burn through hundreds of rounds finding the sweet spot.

 

[Dthomas3523]

Just load and shoot and experiment. Welcome to the fun filled world of reloading where you'll burn through hundreds of rounds finding the sweet spot.

If you’re burning through hundreds of rounds, you’re doing it wrong.

 

[spife7980]

If you’re burning through hundreds of rounds, you’re doing it wrong.

Idk, Ive done it just to see what happens when I change this or that. I loved it.

 

[Rocketmandb]

I've been doing some research on this myself. I saw a an article posted on Berger's website that suggested they now recommend using the seating depth testing first and then moving into a ladder. Of course, I can't find a link now that I want to share the article.

Precision Rifle Blog also has a series of articles on this from back in March that reports on some findings primarily from Short Action Customs:

Bullet Jump: Is Less Always Better?

About 2 years ago, Mark Gordon shared some preliminary research he’d conducted with the Applied Bal...

precisionrifleblog.com

I just got some of the 144 gr. 6.5mm Berger's and I think I'm going to try the seating depth testing then move into ladder testing and see what happens for the load development with those bullets.

I remember reading the Berger piece on their web site and thought, "that makes sense."

But then I could never bring myself to do it I continue to find a good charge weight first, then tune seating depth. With Berger hybrids (regardless of weight), I find they do well at about 25 thousandths off, even if it's not their best (though in many, if not most, it is).

Also, after getting dramatically dismayed by the Precision Rifle Blog post on barrel erosion, I recently did a seating depth test with 105 hybrids in my 6 BRA. My "go to" is .025 off. I tested that vs. .050 and .075. At 850 yards there was very limited difference in the vertical between 25 and 50 off. Both came in at under 1.5" vertical spread. 75 off expanded out a bit to about 4". I didn't do longer, though I will be playing out into the hundreds next time around.

 

[Zack_va248]

I've been doing some research on this myself. I saw a an article posted on Berger's website that suggested they now recommend using the seating depth testing first and then moving into a ladder. Of course, I can't find a link now that I want to share the article.

Precision Rifle Blog also has a series of articles on this from back in March that reports on some findings primarily from Short Action Customs:

Bullet Jump: Is Less Always Better?

About 2 years ago, Mark Gordon shared some preliminary research he’d conducted with the Applied Bal...

precisionrifleblog.com

I just got some of the 144 gr. 6.5mm Berger's and I think I'm going to try the seating depth testing then move into ladder testing and see what happens for the load development with those bullets.

I've been doing some research on this myself. I saw a an article posted on Berger's website that suggested they now recommend using the seating depth testing first and then moving into a ladder. Of course, I can't find a link now that I want to share the article.

Precision Rifle Blog also has a series of articles on this from back in March that reports on some findings primarily from Short Action Customs:

Bullet Jump: Is Less Always Better?

About 2 years ago, Mark Gordon shared some preliminary research he’d conducted with the Applied Bal...

precisionrifleblog.com

I just got some of the 144 gr. 6.5mm Berger's and I think I'm going to try the seating depth testing then move into ladder testing and see what happens for the load development with those bullets.

I read Cals stuff and Marks testing and thats where I pulled the idea to test this way. Just didn't want to get caught chasing my tail with the seating depth shifting with pressure.

 

[Jordanwickham]

I read Cals stuff and Marks testing and thats where I pulled the idea to test this way. Just didn't want to get caught chasing my tail with the seating depth shifting with pressure.

That's why I would advise if you were to go this route to find max pressure first, go to about 3/4 max and do the seating test. For a high node you should be right around the 3/4 max mark.
If velocity is of no concern I would just do it normal.
Or if you have been successful in other load development means I would just stick with that. No reason to reinvent the wheel, unless you are like me and tinker with everything.