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OCW vs Ladder vs Chronograph

Hummmm.....I tune by shooting 3 Shot groups at 100 yards. I use the Chronograph to determine how much change in velocity the barrel can take. I don’t shoot ladders and I can read wind flags so no need to shoot OCW.

Before you tell me that won’t work for 600 and 1000 yard matches. Probably best to check the match results first.

Bart

Could you elaborate on your process? Let's say you're starting from scratch with a new bullet, powder, and brass. Where do you begin, and what process takes you to your greatest chance of success?
 
To me.... every barrel can be tested to it's full potential for accuracy. The TEST is in the trying to control the harmonics of that barrel. Harmonics is effected by all the components that make up the load... that's why simple changes like seating depth... minor powder changes... primer change... burn rate, and even neck tension, are all focused on one thing... and that is the pressure within that barrel. A rough barrel will also effect this pressure...the better the barrel... the more consistent the bullet can rotate out of the barrel. The pressure is trying to force the bullet down the barrel as fast as it can... or as fast as it has been allowed to, by that combination of those components. This pressure is causing the barrel to whip around in unstable conditions. Trying to stabilize the pressure... thus stabilizing the barrel's harmonics is our goal. Barrel tuners force the barrel's harmonics to calm down and stabilize better. A chronograph can tell us the best load that is working in a consistent manner... and that will tell us what the barrel likes... called nodes. Nodes should make barrel harmonics stabilize better. But that node can be narrow or wide, depending on how well the barrel can handle a wide or narrow range of pressures and vibrations. To me... a chronograph can help find a consistent load, and that's why we all want a wide node, and then pick the middle of the road load. But that doesn't mean it will print consistantly because the barrel harmonics can still be off... hopefully NOT....LOL. So.... in my opinion... we are trying to create a consistant pressure, which will create the most stabile barrel as possible.
 
Could you elaborate on your process? Let's say you're starting from scratch with a new bullet, powder, and brass. Where do you begin, and what process takes you to your greatest chance of success?

Adam,

Im not ducking the question but I’ve posted how I tune at length on this board. So a quick search and you’ll find details. Frankly I’m tired of writing it.

Here are some thoughts that may or may not agree with some folks here.

1. Long range guns drift in and out of tune daily, weekly, monthly just like short range guns. The days where a shooter can park on one load all year are coming to an end. Can it be done? Yes, but it would take an exceptional barrel.


2. Correct seating depth is key. A proper seating depth will give you the widest possible load window. Get the seating depth wrong and no matter what load you put in it won’t shoot.

3. With some barrels you can keep the same seating depth for its entire life and it will shoot competitively. Others you’ll have to chase the lands.

4. Humidity helps increase the load window (I don’t know why it just does). As humidity decreases so will the range of your load window. I’ve not shared this before but it’s true.

So for what it’s worth....
Bart
 
How wide is a good seating depth window? Is the Berger depth test a good one to follow or is their increments too coarse?
 
How wide is a good seating depth window? Is the Berger depth test a good one to follow or is their increments too coarse?
Its coarse. When you see the groups shrink start investigating in smaller increments I like .003 per test after charge weight is determined.
 
How wide is a good seating depth window? Is the Berger depth test a good one to follow or is their increments too coarse?

For a hunting gun it’s fine, but that’s not how you want to find the correct seating depth for a competition rifle. I use .003 for course adjustment. Then test on either side for fine tuning.

Bart
 
You read it to mean that any combination would necessarily become consistent, but that is clearly not possible with every combination.

Therefore, a reasonable and thinking person would logically conclude that I meant if it was going to be a consistent burner, then the top of the pressure curve was a likely place for that to happen.

Are we done being ignorant now?
My load went past the top of the pressure curve without being consistent. The first time I had come across this. My thought was the powder may have been to slow so I went to the next faster powder similar results. The next fastest powder (3rd type) which I use a lot of in the same size powder column would have pressure issues at too low a velocity. This is the first time I have ever seen ignition issues with any powder in good condition. My current dead primer bin has between 15 and 20 kgs of used primers in it and that is less than 10yrs old and I have been reloading for more than 50. I found a solution but Magnum primers were not a recommended part of this load combination. Ignorance is only shown by those who do not know they are ignorant of the facts but keep on thinking they know the facts.
 
My load went past the top of the pressure curve without being consistent. The first time I had come across this. My thought was the powder may have been to slow so I went to the next faster powder similar results. The next fastest powder (3rd type) which I use a lot of in the same size powder column would have pressure issues at too low a velocity. This is the first time I have ever seen ignition issues with any powder in good condition. My current dead primer bin has between 15 and 20 kgs of used primers in it and that is less than 10yrs old and I have been reloading for more than 50. I found a solution but Magnum primers were not a recommended part of this load combination. Ignorance is only shown by those who do not know they are ignorant of the facts but keep on thinking they know the facts.
You must live on this site. That post was only up for a few minutes. I deleted it because I thought it was too mean.

I still have no idea what point that you think I made that you are refuting.

I don't really care enough to continue further though.
 
Still learning, from most of this.

Has anyone who has used the chronograph method later gone back and tested the method against a ladder or OCW style workup to get a sense of its validity?
 
I run a Ladder and my Chronograph at the same time at 600 yards ( too Include Shot Marker DATA at the Target Velocity) . Alot of the time they are pretty darn close if your working with a cartridge that is normally Pretty accurate and Normally provides small ES and SD like the 6PPC cases, 6BR case's, 6.5X47 type case's. 284, and so forth. Cartridges that usually or typically have a hard time getting low SD and ES seems to me dont coincide at times. I feel and this is just my opinion with just what I have been noticing with my own data, I will take the ON TARGET DATA over the Chrono flat spots in cases that ussually have a Large ES SD numbers.
Kinda geeky to want to see both i guess when doing a Ladder at 600 yards. But I enjoy it. Again just my opnion.. Hope this finds you all well.
 
I believe that every shooter trying to work up a load should install a high quality.. high power ... target scope for starters.... then later change it out for your desired scope...have at least ONE scope set aside for load workups only.

Last year I bought a Savage Axis 6.5 Creedmoor Scope Combo from Academy Sports for $300.00.
I then removed the combo supplied scope... installed my workup scope... a Bushnell 4200 8-32x40 scope.... and started working up a load, which I ended up with Bug Hole groups with the Carolina Load. But after reinstalling the cheaper combo supplied scope, it didn't do the bug holes as well. This rig was more than good enough for my elderly friend who just wanted a light carry rifle. Point is... start out your load workup with a good scope that will still be clear and sharp on it's highest power... and your shooting rest system has to be rock solid. If either of these is questionable, then so will reading your target groups... at any distance.... and groups to me... are priority.
 
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Couple caveats...
1. I realize sample size is low, I'm doing what I can on my lunch break

2. Sporter weight 300 Win Mag, not as much time between shots as I'd like but see point # 1

3. Other excuses you likely don't care about etc....

4. The red group is a different bullet, for my own curiosity. Otherwise we're using 168 gr A-Max and RL 22. No specific reason for choosing this combo other than I had RL 22 and the 168 I figured would be an accurate bullet that I could use to refine my technique; both with reloading and handling the 300 Win Mag

That being said:
If I understand the concept of OCW, am I correct that I would ignore the better group of 77.7 grains and instead focus on 78.4 to 79.1 being that they appear to share a relatively close average group elevation?

Again, I understand this is not the the best conditions. I'm trying to simply understand the concept and use it going forward to be a better handloader.

Thanks guys for all the helpful responses so far.
 

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