Seating Depth Increments?

[MagnumManiac]

I hear what you hear…..0.006" wide nodes….maybe 0.012" on a big one….

If you are 0.015" off the node, what do you see?

Let's say you choose 0.030" increments…. Then you are 0.015" off at worst.

If you start 0.050" off of ideal and work towards ideal, do groups incrementally shrink until you get to perfect or are groups all over from big to small as you approach the node?

How many shots per group(same oal) as you approach the node? 1? 3? 5? 20? 50? 100?

To answer this, your groups should widen, shrink, widen, but still show no horizontal spread or vertical stringing and stay in that perfect clover leaf pattern. If fliers occur, or strange oblong patterns, then you are not in the node. Most will not see this in a hunting rifle and SAAMI chamber, this is because harmonics and weight will be an influence hiding this. This is why I verify @ 600 with 20 shot groups, it shows the true dispersion and I can then overlay those outcomes, normally 60 shots for my F-class & ELR rifles, to get a true aggregate on different days.
My hunting rifles get 10 shot groups and total 30 shots to get true dispersion, not ideal numbers, but it works for me.
Also, testing seating depth is perfectly fine using 3 shot groups and I will admit I have used 2 shot groups in haste and trying to save components…

Cheers.

 

[YZ-80]

Thank you all. Points to consider in the process of continual improvement in this hobby

 

[USAFRet]

Thank you all. Points to consider in the process of continual improvement in this hobby

I second that. Starting my 30-06 seating depth testing this weekend. My HOWA has a pretty tight chamber and the recommended COAL is usually right off the land by about .005.

 

[TucsonFX4]

I don't have nearly as much reloading experience as many of the folks on here. I've always started with velocity node testing, but this thread has me wondering if I should start with seating depth testing at a starting charge weight? Then move to velocity testing after finding a good seating depth. Thoughts?

 

[USAFRet]

I don't have nearly as much reloading experience as many of the folks on here. I've always started with velocity node testing, but this thread has me wondering if I should start with seating depth testing at a starting charge weight? Then move to velocity testing after finding a good seating depth. Thoughts?

Start at the node testing. You want a load with good SD and ES to work on seating depth. Plus, at least a decent group to work with. You can have good numbers, but if it is shooting 3 inch groups, it is not worth the time and components.

My load has an SD of 5 and ES of 11. It also shot a 3 round group of .94 (I was doing 4 shot groups, but one piece of brass would not load). I am going to try some different seating depths to see if I can improve on that group, although it is completely acceptable for my application. I am a hunter, not a target shooter.

 

[MagnumManiac]

I don't have nearly as much reloading experience as many of the folks on here. I've always started with velocity node testing, but this thread has me wondering if I should start with seating depth testing at a starting charge weight? Then move to velocity testing after finding a good seating depth. Thoughts?

Best out come for me is to use a middle load that is untuned, test seating depth and what you find is true seating depth tune and no powder node influence. It is quick and easy often showing a result within less than 10 rounds fired. Once seating depth is found, it very rarely changes with that bullet in your rifle and it will show more precise powder nodes when you test for groups.
Looking for ES/SD numbers while doing powder nodes is futile, shoot groups, find the tightest group THEN load more and use your chronograph to get the numbers, ES/SD are NOT the be all, end all result, grouping is the better evaluator…

Cheers.

 

[TucsonFX4]

Start at the node testing. You want a load with good SD and ES to work on seating depth. Plus, at least a decent group to work with. You can have good numbers, but if it is shooting 3 inch groups, it is not worth the time and components.

My load has an SD of 5 and ES of 11. It also shot a 3 round group of .94 (I was doing 4 shot groups, but one piece of brass would not load). I am going to try some different seating depths to see if I can improve on that group, although it is completely acceptable for my application. I am a hunter, not a target shooter.

This is pretty similar to what I have been doing. There's certainly a million different ways to skin this cat. Thanks for the reply.

Best out come for me is to use a middle load that is untuned, test seating depth and what you find is true seating depth tune and no powder node influence. It is quick and easy often showing a result within less than 10 rounds fired. Once seating depth is found, it very rarely changes with that bullet in your rifle and it will show more precise powder nodes when you test for groups.
Looking for ES/SD numbers while doing powder nodes is futile, shoot groups, find the tightest group THEN load more and use your chronograph to get the numbers, ES/SD are NOT the be all, end all result, grouping is the better evaluator…

Cheers.

Thanks for the response. I like your method, and I think I'll give it a try.

 

[USAFRet]

This is pretty similar to what I have been doing. There's certainly a million different ways to skin this cat. Thanks for the reply.



Thanks for the response. I like your method, and I think I'll give it a try.

I need to correct what I said. I don't do node testing. I shoot groups and take speed, ES and SD from 2 grains below max to max, in .5 grain increments, looking for a combination of a decent group and decent numbers. Also checking for pressure signs. If I see a couple of groups decent within a grain, I may play around in between those. I then do seat depth testing to try and tighten up accuracy.

 

[USAFRet]

I loaded 4 different seating depth this evening, working my way down in .010 increments to .050 below the recommended COAL. Seeing what I get tomorrow.

 

[Tiny Tim]

I like the Berger method (or some variation of it based upon bullet profile). I also do coarse seating depth testing prior to powder tuning.

I have found that large variations in seating depth (=/>0.015') can cause enough velocity change to move into or out of a "powder node", which may be interpreted as a good seating depth when its not. Once this is established, unless you are inside 0.010" OTL, 0.006 either side of your coarse seating depth won't have much effect on velocity.

 

[USAFRet]

.050 jump. Best group so far. I have one more load set at .060, but did not have time to test.

Full test set

 

[southpa]

I shoot bergers. For a vld I start at .010 and go from .010-.060 in .010 increment. If I have the need to get surgical ill adjust .005 from there but usually .010 increments is good. Like someone already said, I have had good luck with .010 increments and you can really see groups open and close in just those small increments. At least I can.

For a hybrid ill do the same but start at .020. Obviously I'll jump more if I have to but I've found VLDs like it .010'ish and my experience with hybrids is all over. They have been finicky with depths for me.

 

[highfinblue]

I use .010, and have found my rifles generally like them about .020 off the lands, so when I do get a new rifle I want to shoot Bergers out of I generally start there. I'm fairly certain every rifle I've owned but one that I shot Bergers out of liked it right there. Had one 6.5-284 Norma that liked them crammed into the lands, I got tired of cleaning powder out of the action after a hunt and got rid of it. That sucker was too temperamental for me, I'm old, if it ain't easy, I ain't doin it.

 

[6.5x300 WBY]

I am not worried about where my lands are, I only do or start with MAX mag length and work my way in. Lands are a consistently moving thing. I guess i am following Eric Cortina's method and it makes sense to me and for me. I've started to go back by .005 till perfection. Perfection just means to me that my load shoots better than I do.
When my load consistently goes between .3 and .2 I know I am there. I want to be able to shoot better than that but I haven't gotten there YET.