Weighing powder charges for ladder testing .

deergetter · Oct 11, 2020

I am new to ladder testing and would appreciate any comments. I am looking to try a ladder test on my 6.5 Creedmoor . I just purchased a MagnetoSpeed V3 and some Peterson brass hoping for internal volume consistency. I load with a Lyman Gen6 powder measure and check with a Hornady Bench scale before pouring into case. I hear you load 10 or more cartridges in .2 grain increments and look for points were velocity has very small changes for 2 or 3 charge weight gains and that is an accuracy node. I just wonder if I need a more accurate powder weighing method that measures to hundreds of a grain instead of tenths of a grain .Thanks in advance for any help .

troy fairweather · Oct 11, 2020

Tenths will be fine, I wouldn't use the magnospeed,

Ruger 15151 · Oct 11, 2020

Most use a version of this method to identify accuracy nodes ( plateau in velocity that are .4 gr -.6 gr wide ) where the POA of consecutive groups are in he same place.

http://optimalchargeweight.embarqspace.com/

Then you experiment with seating depth until your groups tighten up even more.

Here is another video by Erik Cortina - Manager for Team Lapua and world class shooter that explains how to find your seating depths (jump to the lands)

Hope this info helps

Blue68f100 · Oct 11, 2020

When I'm doing load workup I always check the electronic dispenser for accuracy. I want the loads as close to actual as they can be. I weight every round with my GemPro 250 scales that have been verified with check weights. Once I find what the node size is the auto dispenser is close enough. I know for my 6.5 CM I have a velocity window of about 25 fps that I must be in.

whughett · Oct 11, 2020

Tenths of a grain is coming down to “kernels” of powder in most powders. How one would one measure 1/100’s of a grain. Would need to be a fine powder indeed.

deergetter · Oct 11, 2020

troy fairweather said:
Tenths will be fine, I wouldn't use the magnospeed,

Thanks for the reply fairweather . I was just curious why you wouldn't use the MagnetoSpeed . I do also have an optical Chrono . I wasn't planning on shooting groups at this point . I do see many people shoot groups with the bayonet on the rifle and they say it changes point of impact but not group size.

deergetter · Oct 11, 2020

Ruger 15151 said:
Most use a version of this method to identify accuracy nodes ( plateau in velocity that are .4 gr -.6 gr wide ) where the POA of consecutive groups are in he same place.

http://optimalchargeweight.embarqspace.com/

Then you experiment with seating depth until your groups tighten up even more.

Here is another video by Erik Cortina - Manager for Team Lapua and world class shooter that explains how to find your seating depths (jump to the lands)

Hope this info helps

Thanks Ruger 151 , I have seen those videos and love them . My concern is that when only increasing powder charges by .2 grains on scales that are only accurate to .1 grain +or - may not be accurate enough . Maybe I should go in .3 grain increments , also what are your thoughts about the Magneto Speed verses an optical chrono . I am waiting for my Magneto Speed to be delivered or I would already have that answer.

deergetter · Oct 11, 2020

Blue68f100 said:
When I'm doing load workup I always check the electronic dispenser for accuracy. I want the loads as close to actual as they can be. I weight every round with my GemPro 250 scales that have been verified with check weights. Once I find what the node size is the auto dispenser is close enough. I know for my 6.5 CM I have a velocity window of about 25 fps that I must be in.

Thanks, Blue . I see a lot of people like the GemPro 250 scales . I see many people pushing the lab quality $1000.00 set ups . I just can't justify that . At 71 yrs old and shooting off the shelf sporters at 100 yds it does not add up to me . Thinking about an A&D EJ-123 or similar .

troy fairweather · Oct 11, 2020

deergetter said:
Thanks for the reply fairweather . I was just curious why you wouldn't use the MagnetoSpeed . I do also have an optical Chrono . I wasn't planning on shooting groups at this point . I do see many people shoot groups with the bayonet on the rifle and they say it changes point of impact but not group size.

It will affect the latter test if it's on the barrel, messes with the barrel harmonics.

deergetter · Oct 11, 2020

whughett said:
Tenths of a grain is coming down to “kernels” of powder in most powders. How one would one measure 1/100’s of a grain. Would need to be a fine powder indeed.

Yes . I have tweezers that I use on stick powder when I use my Hornady Bench scale . I see people measuring 1 kernel of H4350 at 2 one hundreds of a grain.

deergetter · Oct 11, 2020

troy fairweather said:
It will affect the latter test if it's on the barrel, messes with the barrel harmonics.

I agree your theory holds water , it's just that almost all people I see doing ladder testing use the MagnetoSpeed .My Magneto Speed is on order and I have an Optical Chrono . I will check that out when I get it .

JFrank · Oct 11, 2020

I use a simple beam scale, as long as I use the same scale for loadin and testin I’m fine.
.2 grains is about 10 kernels of 4831sc
That’s plenty of incremental change per charge.

deergetter · Oct 11, 2020

South Prairie Jim said:
I use a simple beam scale, as long as I use the same scale for loadin and testin I’m fine.
.2 grains is about 10 kernels of 4831sc
That’s plenty of incremental change per charge.

You're probably right . We can spend lots of money and chase our tails for very little results .

JFrank · Oct 11, 2020

If you already use this method than disregard the following;
We normally have a good idea of the range we want to explore, we also color the bullet ogive with different sharpies, say three of each than shoot them at one point of aim as posted below.
From there it’s some what of a matter of perspective however we choose a group that is small and hopefully overlapping than test again on each side of that charge. This is my son in laws load development for the 270 WSM.

JFrank · Oct 11, 2020

So he can load anywhere in the 58.5-58.6 and have those rounds hit nearly identical location on the animal or target depending on how well he manages recoil that day

deergetter · Oct 11, 2020

The color on the bullets actually transfers to the target . That interesting and useful information . I will have to try this .

Ruger 15151 · Oct 11, 2020

The MagnetoSpeed is definitely the way to go if you can't afford a Labrador. Mounting it on the barrel doesn't always effect the POI. It depends on the barrel and caliber. Guys mount them on their barrels during ELR competitions to read every shot to identify if a miss was due to a velocity variation. On my .308 and 6.5CM, they effect POI and group size even when they are mounted from the picatinny rail and not the barrel. However, my Labrador is only used to give me the velocity on a given day so I can have my ballistic calculator prove accurate DOPE

However, with the OCW method that I sent you, you don't need a chrono to identify accuracy nodes. You are looking for similar POI among groups. Once you see multiple groups with a similar POI ( regardless of group size), then that is where your accuracy nodes are (velocity plateau). There are usually at least one high and one low and are spread over a .5gr depending on the powder. I load ladders of three rounds in .3gr increments. Once I have identified where the nodes are, I load in .2 grain increments on both sides of those groups to identify the center of the node. Once you have found the ends of the node, you pick a charge in the middle. If your testing is accurate, you can load .1 and sometimes .2grs on either side of this charge without a change in velocity (which means without a change in POI). That's why you will see world class shooters load on a charge master with a +/_.1gr accuracy because it doesn't effect the velocity or POI.

Once I have found a load using the OCW method, I'll run it over the chrono to verify that the SD/ES numbers are good.

EDIT: Sorry. needed to fix the grammar so it reads like English! I guess my coffee hadn't kicked in!

deergetter · Oct 11, 2020

Ruger 15151 said:
The magneto speed is definatley the way to go if you cant afford a Labrador. It doesn't always effect he POA, It depends on the barrel and caliber. Guys mount them on their barrels during ELR competitions to read every shot to identify if a miss was due to a velocity variation. On my .308 and 6.5CM, they effect POA and group size even when they are mount ed from the picatinny rail and not the barrel. However, my chrono is only used to give me the velocity on a given day so I can have my ballistic calculator prove accurate DOPE

However, with the OCW method that I sent you, you don't need a chrono to identify accuracy nodes. You are looking for similar POA among groups. Once you see multiple groups with a similar POA ( regardless of group size), then that is where your accuracy node (velocity plateau) is. There are usually at least one high and one low and are spread over a .5gr depending on the powder. I three rounds in .3gr increments. Once I have identified where the nodes are, I load in .2 grain increments on both sides of those groups to try to identify the center of the node. Once you have found the ends of the node, you pick a charge in the middle. If your rtesting is accurate, you can load .1 and sometimes .2grs on either side of this charge without a change in velocity (which means without a change in POA). That's why you will see world class shooters load on a charge master with a +/_.1gr accuracy because it doesn't effect the velocity or POA.

Once I have found a load using the OCW method, I'll run it over the chrono to verify that the SD/ES numbers are good.

deergetter · Oct 11, 2020

Ruger 15151 , You and a few others have given me some very useful information to work with . I was looking at both the Magneto Speed and the Labradar and almost squeezed the trigger on the Labradar but read some reviews that pushed me away . I am a 71 yr old spoiled kid and will probably buy one just to compare . The concept of not having to shoot through it as with the opticals and not having to worry about it loosening up on tapered sporter barrels , and changing barrel harmonics and point of impact as with the Magneto Speed. I would like to hear your experience with your Labradar . I hear it is tricky to set up and get properly aimed at target . Your input would be appreciated. I moved to Tennessee 6 years ago and find it difficult to find people that take shooting and handloading to the degree I like to .

lordpaxman · Oct 11, 2020

The OCW method finds a charge weight that, in a range of weights, doesn’t affect POI. Nothing more. It’s usually an accuracy node and velocity node, at least for the few rifles I’ve tried it on.
I did splurge on a LabRadar and found it to be so much easier than an optical chrono. It does have a little learning curve but not a bad one. I’d recommend it if you have the $$. Good luck.

MOP.GBB · Oct 11, 2020

There are a couple good youtube videos on electronic scales and "normal" variance. Cliff notes version, most measure in .2 grain increments ("point" "two"). Obviously, the big money scales are more precise. I will usually throw a charge about .3'ish grains under my target weight. I'll use a trickle charger to bring it up to the desired weight while it's sitting on the scale.

Laphroaig · Oct 11, 2020

deergetter said:
I see people measuring 1 kernel of H4350 at 2 one hundreds of a grain.

I just loaded some IMR4895 and checked weights on a Gempro 250. I came to the conclusion that a kernel of 4895 also weighs .02 grain. That's not something that I do every day!

Ruger 15151 · Oct 12, 2020

deergetter said:
Ruger 15151 , You and a few others have given me some very useful information to work with . I was looking at both the Magneto Speed and the Labradar and almost squeezed the trigger on the Labradar but read some reviews that pushed me away . I am a 71 yr old spoiled kid and will probably buy one just to compare . The concept of not having to shoot through it as with the opticals and not having to worry about it loosening up on tapered sporter barrels , and changing barrel harmonics and point of impact as with the Magneto Speed. I would like to hear your experience with your Labradar . I hear it is tricky to set up and get properly aimed at target . Your input would be appreciated. I moved to Tennessee 6 years ago and find it difficult to find people that take shooting and handloading to the degree I like to .

There is a little bit of a learning curve with a Labrador but once you get the hang of it, setup is very easy.

For me, learning proper loading techniques and load development is something I really enjoy. However, it takes a great deal of patience as isn't for everyone. I live on the west coast where there are even fewer precision loaders. I continue to gathered new reloading technique from guys on this forum like Walkalong, LiveLife, NatureBoy, and a few others as well as through YouTube videos from experts like Bryn Litz ( Berger Bullets ballistician and world class shooter), Erik Cortina ( Manager of Team Lapua and world class shooter)and guys of that caliber. However, I have also learned a great deal from guys at shooting matches. The top competitors at matches are always willing to share information that will help you with equipment, load data, and loading techniques. You don't even have to be competing in the match to ask questions. I have found everyone is very approachable and usually very helpful.

Find a long range or PRS match in your area and go watch. I guarantee you will learn something every time you go

JFrank · Oct 12, 2020

Ruger 15151 said:
There is a little bit of a learning curve with a Labrador but once you get the hang of it, setup is very easy.

For me, learning proper loading techniques and load development is something I really enjoy. However, it takes a great deal of patience as isn't for everyone. I live on the west coast where there are even fewer precision loaders. I continue to gathered new reloading technique from guys on this forum like Walkalong, LiveLife, NatureBoy, and a few others as well as through YouTube videos from experts like Bryn Litz ( Berger Bullets ballistician and world class shooter), Erik Cortina ( Manager of Team Lapua and world class shooter)and guys of that caliber. However, I have also learned a great deal from guys at shooting matches. The top competitors at matches are always willing to share information that will help you with equipment, load data, and loading techniques. You don't even have to be competing in the match to ask questions. I have found everyone is very approachable and usually very helpful.

Find a long range or PRS match in your area and go watch. I guarantee you will learn something every time you go

On the west coast ?
You may be interested in the NBRSA 600 & 1000 Nationals that start this week I believe in Sacramento

Weighing powder charges for ladder testing .

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Attachments

Member

Member

Member

Member

Member

Member

Member

Member

Member

Member

Similar threads