Question about a load development method ....

Listening to Lou Murdica today on YouTube, he said….start with the bullet in the lands and adjust the powder charge, then finish your tuning with bullet seating depth. He was saying for Fclass, he uses 0.003" increments. He also suggested that the "node" might be 0.012" wide.

lots of interesting stuff with those videos.
 
Listening to Lou Murdica today on YouTube, he said….start with the bullet in the lands and adjust the powder charge, then finish your tuning with bullet seating depth. He was saying for Fclass, he uses 0.003" increments. He also suggested that the "node" might be 0.012" wide.

lots of interesting stuff with those videos.
If anybody knows Lou Murdica does…he was Berger's bullet testing lab for many years.
 
I have been loading for 35 years and I am NOT half as good as some members on this forum. Let alone some of the competition shooters. In fact I am learning new things every day. So here are my two cents and take it for what you oaid for:
It depends on what you are loading for. Hunting or competition. For competition, your throat will erode during the match and you want a for giving seating depth
Not all bullets are created equal. Some like jump some don't. In fact Berger has different recommendations for different bullets
Not all calibers are created equal. Standard versus magnums versus ultra.
When I started out, it was OCW then satterlee, ladder, modified one or another then bullet jump. Throw in barrel harmonics, OBT and nodes.
You can get to the same point in many ways and you will get many opinions and suggestions. And burn different amounts of powder and bullets
The engineer in me has to analyze the suggestion, understand it and then try it
Find what works for you, and for what you are trying to do
 
What sort of powder charge do you use when doing Bullet Seating?
When you try a different primer do you repeat step 1? Or just compare Primer A to Primer B for the powder charge you're using?
I derive initial powder using QuickLoad. It's the fastest(and coolest of fastest) powder that fills the case at SAAMI max pressure.
For full seating testing I'm basically following Berger's recommended testing(COARSE TESTING), with it's prerequisite back down in load.
Starting load as Quiet Texan mentioned ~93% is good. That back down is not for safety, but to be clear of any probable powder node.
You don't need to be going in/out of a powder node while trying to see only results of coarse seating.

Initial primer testing for me has simply been swapping through 4 or 5 different primers, 3sht grouping each.
Like seating, this is a very coarse adjustment. Just looking for what obviously looks best.

What's important to understand in this is that each on my list is mostly independent of one another.
Yeah, everything wiggles into a tight relationship in the end, but they still stand as individual attributes.
And you could test seating later, primers later, but that's a backwards calibration IMO.
How am I going to produce a legit powder ladder if using a wrong primer and worst seating?
And what's gonna happen to my perfect powder node if I change seating and swap primers?
What are the odds that I could just pull the best of primers and seating depth out of my butt to begin?

I go back to seating for a fine testing/adjustment, and then finally to neck tension testing.
If you think I'm adding a bunch of shooting with these things,, I'm not actually.
Coarse seating and primers were completed during fire forming of cases, which must be done for credible powder testing anyway.
It's a logical progression.
It's also logical to reach best hot precision before moving to cold bore accuracy testing.
I could and do mangle hot bore grouping loads for best cold bore accuracy, but I needed to start somewhere.
 
Last edited:
The right powder for your particular gun will make all the difference in the world in terms of forgiveness and overall the most accurate. Without that, it's an uphill climb depending on how accurate you want to be.
How to find a forgiving powder ?
Run a ladder test in .3 increments and the powder that is the most forgiving will not stray far from a vertical string. The powder that stretches more out horizontally in that vertical string will be less forgiving.
You can't lay a solid foundation for a load with an unforgiving powder so start there. The powder is your foundation and will make everything else work together a lot smoother.
 
Essentially what we're all saying is before the first shot you have to decide on several things to build the initial round: bullet, powder, charge, primer, COAL.

Which of those is the first variable you mess with after you make your initial choices is the question - we're discussing which of the initial assumptions is the best to change first. I said coarse seating depth first. Doesn't mean that changing powder first is wrong by any means, a simple explanation of why two rational people make the opposite decision in this case is the "change charge first" guy feels better about his seating depth than I do about my powder selection/charge. There's approximately all the data in the world about H4831 in the 6.5-284 case with 140s, should be a rock solid starting place on the charge weight in that situation, but VLDs can still be tough to tune - seating depth first.

Why might he feel better about his seating depth? I feel better about depth in some cases also. I'm getting a reamer made for a new barrel, the first adjustment I will make in that loading cycle will be charge weight because the chamber is going to be cut a certain way for the bullet that will be sat in it. I'm going to start a lot closer to the optimal seating depth in the first place compared to stuffing a 115gn Berger into a factory 243 WIN chamber, it should shoot well out of the box at 0.020" off because it was built around that assumption. Still going to test it, but should be easier than going into a new chamber I know nothing about.
 
Last edited:
Ive been using OBT for a while now and it gets me there fast and with fewer rounds. I know many discount it but it works for me every time.

I've tried this a few times and couldn't get it to work for me. How have you been getting the estimated barrel time number? If quickload, are you using the 10% to bullet exit number?
 
I derive initial powder using QuickLoad. It's the fastest(and coolest of fastest) powder that fills the case at SAAMI max pressure.
For full seating testing I'm basically following Berger's recommended testing(COARSE TESTING), with it's prerequisite back down in load.
Starting load as Quiet Texan mentioned ~93% is good. That back down is not for safety, but to be clear of any probable powder node.
You don't need to be going in/out of a powder node while trying to see only results of coarse seating.

Thanks for all this great information! Had a couple more questions.

How do you determine the 'coolest'powder?

You mentioned you use the Berger approach for initial seating depth. Is that the 0.040" seating depth steps?
 
Back in 2018 I switched to the Scott Satterlee "10-shot Load Development" method then later made some changes after watching Pro F-Class Shooter Erik Cortina's video's on the subject. I stopped neck sizing and am now full length with a 2-thou shoulder bump. My reload process got simpler and my consistency improved.
Saves a lot of components also along with it being easier for me anyway, other folks have proven methods that will end up with the same results in the end but will take considerable more time and using more materials, try all the different methods and settle on what works best for you. A good chronograph and learning to read velocity nodes goes a long way in reloading. I have been reloading since the early eighties and have had good success using a variety of starting points. The Nosler reloading guide will give you the most accurate powder tested, as well as the most accurate powder charge. It is not perfect but will definitely put you in the ballpark for most bullets and powders.
 
What sort of powder charge do you use when doing Bullet Seating?

When you try a different primer do you repeat step 1? Or just compare Primer A to Primer B for the powder charge you're using?
If you find an accurate load in the velocity range that you are looking for but have extreme ES & SD, often times a primer change will tighten up those numbers for you, at least they sometimes have for me, but not always. Sometimes a non-magnum primer is the ticket, even in magnum rifles like the 300WM.
 

Recent Posts

Top