Bad SD and ES but good group...

[RTTY]

For what it's worth I would pick 38.7gn or 39.0 (or a load in between) as a test with +/- 0.2 gn on either side in absence of any other information. 5 shot groups. See if the POI repeats. If it does then you can work on seating depth and see if the groups tighten up.

A friend of mine achieved excellent results with a 38.7gn.
We have the same gun, the only differences are the twist rate (mine is 8" and his is 8.5") and barrel length (mine is 28" and his is 26"). We use the same brand of cases, the same bullet weight and type.
I use Fiocchi SRM primers, he uses Federal, and obviously the same powder.
He's much better at shooting than me and has been doing it much longer. I'll do as you suggest!

Thanks.

 

[Old Man with Gun]

Well, so I choose the group with better consistency and see what it gives me in the long distance

Unless the SD is low, it will not perform well at distance regardless of how well it shoots up close.

 

[Old Man with Gun]

I'll follow your advice.
But are you telling me to develop around the groups with the best SD and ES?

You can find good SD through charge weight, good SD should be decent groups, they have consistency.

You can then try to shrink the groups using seating depth, neck tension, etc.

It is common to find that a cartridge/ powder/ bullet combination works well in a lot of different firearms. Where the rifles tend to vary, is in best seating depth.

 

[Old Man with Gun]

This is what works for me, so I thought I'd share. I start looking for a range of powder charges that give good SD/ES with 5 shot groups. I got good numbers between 42.3 and 43.1. Even though 42.7 is higher than 42.3 or 43.1 I'm incuding it, because I'm looking for the node to start.

Then, within that range, I shoot 10 shot groups for better data and realistic group sizes. As luck has it, 42.7 was my lowest SD that day, although later testing puts it more like 7-9.

Depending on my goals, I'll either pick something like 42.8 and run with it, or do some 15 shot groups at 42.7, 42.8 and 42.9 before choosing.

If I want smaller groups, I'll play with seating depth, knowing I have a low SD / ES to start with.

 

[Rodney65]

Your SD and ES variation in velocity is undetectable on group size at 100 yds or meters. In most centerfire rifles a 100ft/sec (30 m/sec) only varies the point of impact about 1 caliber. The velocity effect is only one factor in the dispersion equation as in reality many things (bullet, case, powder, neck tension, etc) change from shot to shot. As the distance to target gets larger then the ES/SD will have a greater effect on dispersion.

While I completely agree high EDs and SDs aren't going to change POI at 100 yards could they not possibly indicate a consistency issue somewhere that would help both 100 yard group sizes and velocity consistency if addressed?

 

[RTTY]

Unless the SD is low, it will not perform well at distance regardless of how well it shoots up close.

Thank you for this advice too.
When I have the powder from the first test I posted again, I'll do a new test to perhaps confirm or deny what the first test showed.

Thanks.

 

[RTTY]

You can find good SD through charge weight, good SD should be decent groups, they have consistency.

You can then try to shrink the groups using seating depth, neck tension, etc.

It is common to find that a cartridge/ powder/ bullet combination works well in a lot of different firearms. Where the rifles tend to vary in what they like is seating depth.

Yes, if I can get similar or very similar results to the first test, I'll play with the bullet seating depth.
As for weighing the powder, I weigh it and check it with two scales.

 

[RTTY]

This is what works for me, so I thought I'd share. I start looking for a range of powder charges that give good SD/ES with 5 shot groups. I got good numbers between 42.3 and 43.1. Even though 42.7 is higher than 42.3 or 43.1 I'm incuding it, because I'm looking for the node to start.

View attachment 8765381

Then, within that range, I shoot 10 shot groups for better data and realistic group sizes. As luck has it, 42.7 was my lowest SD that day, although later testing puts it more like 7-9.
View attachment 8765382

Depending on my goals, I'll either pick something like 42.8 and run with it, or do some 15 shot groups at 42.7, 42.8 and 42.9 before choosing.

If I want smaller groups, I'll play with seating depth, knowing I have a low SD / ES to start with.

Thanks for the very clear example. How low did you stay compared to the maximum charge?

Is the table you posted an Excel spreadsheet? If SD and ES are calculated automatically?

Why did you mark the 43.1gn load as "better"?

 

[Old Man with Gun]

The notes under group was to explain that even though one load may get the best group, a charge close to it may be a better pick if in the middle of the node.

Nice thing about being in the middle of good SD is if conditions change a little bit like temperature or altitude, you are still good.

I settled on 42.8, I'll take consistent percission over another 50 fps every time.

Yes excel formulas

 

[RTTY]

The notes under group was to explain that even though one load may get the best group, charge close to it may be a better pick if in the middle of the node.

Nice thing about being in the middle of good SD is if conditions change a little bit like temperature or altitude, you are still good.

I settled on 42.8, I'll take consistent percussion over another 50 fps every time.

Yes excel formulas

OK, I get it!
You preferred a slightly larger SD load that would allow for higher speeds.

 

[RTTY]

Hello are my case prep procedure correct? :

Cleaning the case
Depriming
Cleaning the primer seat and flash hole Recalibrating the neck with die neck and bushing .291"
Cleaning the case
Annealing
Cleaning the inside of the neck with a bronze brush
Recalibrating full with bushing .287"
Redding dry lubricant
Expander .262"
Trimming if necessary
Deburring and chamfering
Priming
Loading
Seating

 

[Maurygold]

Hello are my case prep procedure correct? :

Cleaning the case
Depriming
Cleaning the primer seat and flash hole Recalibrating the neck with die neck and bushing .291"
Cleaning the case
Annealing
Cleaning the inside of the neck with a bronze brush
Recalibrating full with bushing .287"
Redding dry lubricant
Expander .262"
Trimming if necessary
Deburring and chamfering
Priming
Loading
Seating

For me that’s way too many steps. You’re also way over working brass with a neck and fl die. Every step is an opportunity to induce inconsistency.

My process:

Deprime
Vibratory clean with media
Anneal
FL size
Giraud (chamfer, trim, debur)
Vibratory clean again
Prime
Powder
Seat

I don’t believe in Mandrels being necessary (I shoot 4-8 sd without them) but you would mandrel after the fl

 

[Old Man with Gun]

OK, I get it!
You preferred a slightly larger SD load that would allow for higher speeds.

No, I go for the best SD I can get that also groups well. If you need more velocity get a different cartridge.

But, I look for a good range and like to land in the middle. I could have picked 42.7, 42.8 or 42.9 all has single digit SD and had good groups. I chose 42.8 as being in the middle over 42.9 that is slightly faster. Better for consistency and less likely to open up SD and group size if conditions are different from testing day, such as much hotter or colder. Also, should stay true longer as throat erosion happens over time.

 

[straightshooter1]

I always want good SD's (ES's will follow suite) as I've always said before . . . it's what tells me whether I'm loading my cartridges well nor not. But SD's don't tell me which load gives me the best results on targets. It's the targets that tell me what the best load. But yes, you can't have good results on target unless you also are able to produce good SD's. They're just not the determining factor for which load is the best.

Focus on the target results when deciding which load is best!

If one is not getting good SD's, then one needs to focus on, examine and improve one's reloading procedure.

 

[RTTY]

For me that’s way too many steps. You’re also way over working brass with a neck and fl die. Every step is an opportunity to induce inconsistency.

My process:

Deprime
Vibratory clean with media
Anneal
FL size
Giraud (chamfer, trim, debur)
Vibratory clean again
Prime
Powder
Seat

I don’t believe in Mandrels being necessary (I shoot 4-8 sd without them) but you would mandrel after the fl

You're right, but the neck of the fired case measures .294".
I've read on this forum and others that you shouldn't resize the neck more than .004" or a maximum of .005" at a time to avoid runout.

Anyway, if you look at the second table with RS50 SD powder, it's good, don't you think? I think the type of powder, relative to the caliber and type of gun, is very important for achieving an excellent reload.

 

[RTTY]

No, I go for the best SD I can get that also groups well. If you need more velocity get a different cartridge.

But, I look for a good range and like to land in the middle. I could have picked 42.7, 42.8 or 42.9 all has single digit SD and had good groups. I chose 42.8 as being in the middle over 42.9 that is slightly faster. Better for consistency and less likely to open up SD and group size if conditions are different from testing day, such as much hotter or colder. Also, should stay true longer as throat erosion happens over time.

Ok, now I understand

 

[Old Man with Gun]

For me that’s way too many steps. You’re also way over working brass with a neck and fl die. Every step is an opportunity to induce inconsistency.

My process:

Deprime
Vibratory clean with media
Anneal
FL size
Giraud (chamfer, trim, debur)
Vibratory clean again
Prime
Powder
Seat

I don’t believe in Mandrels being necessary (I shoot 4-8 sd without them) but you would mandrel after the fl

I agree, the Internet has people worried about too many steps and overthinking it. Most "influencers" podcasts should be called "Look at my sponsors products while I over think this"

Remember that FGMM is able to come up with a load that shoots well in 99% of all firearms. Many of my loads are me trying to mimic FGMM bullet and velocity as a starting point.

My process is the same as yours less the annealing. I keep track of firings by batch.