load development

[mdram]

can someone point me to a primer or 2 on load development.
i have been reading a bit, and there are varying methods
not 100% sure where to start.
something with and without a chrono would be good

[JASmith]

The Grendel Reloading Handbook has a good discussion.

See http://ar15buildbox.com to get a set.

[mdram]

The Grendel Reloading Handbook has a good discussion.

See http://ar15buildbox.com to get a set.

i have them, i will look again, its been a while since i read them

[JASmith]

A lot will depend one what one’s load development goals are.

Working up a safe load for hunting may not require top-end accuracy, which means the work up is less involved.

There are several subscribers to this forum that can offer advice should the goal be to wring the best accuracy from you rifle.

Some folks like to get extremely precise loads for hunting too to get better confidence with shot placement.

[nawagner]

Lot's of different processes. One of the biggest keys is do not change more than one variable at a time and take notes to keep track of what you've done.

[Rosecrans1]

As Nawgner states above. This is very important. And almost any reloading manual has their take on load development. It's important to stay within the published load development perimeters and to NOT discount a bad result permanently. I went back to loads I tried before my rifle(s) were truly broken in and had great results. And everyone has bad days at the range due to all kinds of issues. From weather to "it just isn't going to work today" things.
An average group size is worth looking at again. You can control almost every variable in load development except two. The weather and how you may be shooting on any given day!

[mdram]

thanks guys
the goal is accuracy, and squeezing out as much as i can

my confusion lies with the various methods of ladder testing, and the various methods
do they all yeild the same results?
1 round per charge, up to 5 or more per charge.
whats enough to establish the node?

shoot at one target with colored bullets, or diff targets?

[JASmith]

thanks guys
the goal is accuracy, and squeezing out as much as i can

my confusion lies with the various methods of ladder testing, and the various methods
do they all yeild the same results?
1 round per charge, up to 5 or more per charge.
whats enough to establish the node?

shoot at one target with colored bullets, or diff targets?

Most of the ladders and round robin methods I’ve seen are cast as ways to minimize the number of shots needed to get to a competitive load.

This makes a lot of sense when one is working a large capacity round where accurate barrel life may be 1,000 shots or less. In these cases, using 100 shots to settle on the load of choice makes a difference in how soon the barrel must be swapped and start the process again.

We Grendeliers are very fortunate in that we routinely see accurate barrel life spans of several thousand rounds and more.

That allows us to use a lot more shots in load development (and makes for good bench practice too!).

That’s why I lean toward ladders of at least 3 to 5 shots per charge weight or depth of seating. One can also go with the implied suggestion by Rosecrans1 and repeat the most interesting ladders on a different day.

Further, I also like to plot x & y coordinates of the holes to get a visual understanding of trends.

Going with something like this approach will yield results and get you started on finding the technique that works best for you. After all, those other methods worked for at least the author and might for you too!

[grayfox]

I'm with JA basically. I think a lot of the ladder techniques are different flavors of the same thing...
I tend to prefer a method that relies almost purely on mechanical and engineering stuff, and takes the shooter and any of his errors/deltas out of the equation. Wonder why... ha.
Anyway we all have written on this so do a search and try the flavor you like.
start low.
develop a powder/bullet/graph curve for your gun
Change only 1 parameter at a time
take notes, lots of them.

[1Shot]

Also remember you can't make a purse out of a sow's ear. All the load development in the world will not make a poor quality barrel or set up shoot super accurately. Learned from the school of hard knocks to spend the money on a top quality barrel that you would put into a poor quality barrel trying to find something that will shoot in it. Many trips to the range burning gas and the price of components wasted add up quickly. Most top quality barrels will shoot most anything you put into them and load development is quick and cheap.

[mdram]

Also remember you can't make a purse out of a sow's ear. All the load development in the world will not make a poor quality barrel or set up shoot super accurately. Learned from the school of hard knocks to spend the money on a top quality barrel that you would put into a poor quality barrel trying to find something that will shoot in it. Many trips to the range burning gas and the price of components wasted add up quickly. Most top quality barrels will shoot most anything you put into them and load development is quick and cheap.

yeah, thats why i sprung for a bartlien at the start. i am @ 1moa or better with most factory. just want to see what it can do
receiver was trued, and bedded with blue loctite, matched bolt, all that stuff. the rest is up to me, assuming i did everything right

[Mad Charlie]

You have been doing your due diligence, you're going to do fine.

[Harpoon1]

yeah, thats why i sprung for a bartlien at the start. i am @ 1moa or better with most factory. just want to see what it can do
receiver was trued, and bedded with blue loctite, matched bolt, all that stuff. the rest is up to me, assuming i did everything right

If your looking for “F-Class” accuracy, ive had success with this method, it seems to work well. Of course it’ll work for PRS, hunting loads, etc,.. also, just depends on how much time you want to invest in each load. You can bumble around with other methods but this guy has a proven track record. Not saying it’s the only way, just a proven method with results that is very simple, quick and straightforward to execute.

Edited: Another plus is you can do almost the entire load work up at 100 yards, no need to find a 600-1000 yard range to test, at least until final BC validation.

http://forum.accurateshooter.com/threads...s.3814361/

He also has several YouTube videos, including ”chasing the node”.

https://youtu.be/oRXlCG9YZbQ

[grayfox]

If I might (gently!) add $0.02 worth:
1. The guy is obviously a great shooter, so can be fairly certain that a vertical group is all due to the cartridge charge, not due to 100's of perturbations a shooter could add (one who is not as good as he is). No disrespect! But sometimes for us more normal-accurate shooters center-shifts/alignments on a target might be due to something I did, and not the load.

2. The 0.5 grs charge delta in his ladder is, I think, more of a 1% case volume charge delta. For the Grendel I would suggest using 0.3 as your delta (~1%). Personally I like 0.2 grs b/c being slightly less than 1%, I should always have at least 1 load near that node I'm looking for.

$0.02, respectfully.

[Harpoon1]

1. The guy is obviously a great shooter, so can be fairly certain that a vertical group is all due to the cartridge charge, not due to 100's of perturbations a shooter could add (one who is not as good as he is). No disrespect! But sometimes for us more normal-accurate shooters center-shifts/alignments on a target might be due to something I did, and not the load.

And this is precisely why the test is conducted at 100 yards. It’s more diagnostic of the load, rather than the shooters ability and/or influence of the wind.

2. The 0.5 grs charge delta in his ladder is, I think, more of a 1% case volume charge delta. For the Grendel I would suggest using 0.3 as your delta (~1%). Personally I like 0.2 grs b/c being slightly less than 1%, I should always have at least 1 load near that node I'm looking for.

IIRC, he’s talking about tuning his 6BR and 6x47 Lapua, so, .5 grs delta is more than 1% case volume. As a ratio, for the Grendel, maybe .4 grs would be more appropriate, at least initially. I thought that would have been obvious. For example one wouldn’t use the same increments for the 17 Hornet as you do for the 338 LM but if you think that is confusing for some people, then fair enough. Once you have completed the seating depth phase, you would revisited the charge weight and move up and down in .1 of a grs increments to find the exact center of the optimum charge weight node. Load toward the top end in the winter, lower end during the summer.

FWIW using his method, you don’t need the added precision of .2 grs accuracy initially because you go back and locate the exact center of the optimum charge weight using .1 grs increments after the seating depth test has been completed. Reasonable people can disagree!

[Harpoon1]

1. The guy is obviously a great shooter, so can be fairly certain that a vertical group is all due to the cartridge charge, not due to 100's of perturbations a shooter could add (one who is not as good as he is). No disrespect! But sometimes for us more normal-accurate shooters center-shifts/alignments on a target might be due to something I did, and not the load.

And that’s exactly why you shoot the test at 100 yds, to try and neutralize as much of the shooters ability or lack there of, and x-wind component as possible. Now if you can’t shoot reliable groups at 100 yds, then this method is not for you and you should find a system/method more complimentary to your personal skill level.

2. The 0.5 grs charge delta in his ladder is, I think, more of a 1% case volume charge delta. For the Grendel I would suggest using 0.3 as your delta (~1%). Personally I like 0.2 grs b/c being slightly less than 1%, I should always have at least 1 load near that node I'm looking for.

Well, respectfully, that’s not accurate. Its right there in the first paragraph, he’s loading for the “6.5x47 Lapua”, so the median charge weight is a lot closer to 40.0 grns, in fact 40.0 is what he settled on. So, obviously .4 would be 1%. He uses .5 simply to cover more ground and “cut to the chase”, you don’t need precision at this stage, you’ll refine it later at the end of the testing.

For the Grendel .3 would be closer to 1 % max charge, so .4 seems appropriate for this phase of the test. “Right Church, wrong pew” is, again, satisfactory at this point. Once the seating depth test is complete, then you revisit finding the exact charge weight more precisely. Working out in both directions in .1 increments to locate the exact center of the node at the new seating depth. Even if you nailed it initially with your .2 grn increments, you still need to verify after you’ve done the seating depth test. So, you actually haven’t gained any advantage using smaller increments, you’ve unnecessarily burned up twice as many components trying to locate a precise node early in the test, when an “adequate” powder/velocity node would have sufficed.

Not saying your way of doing it is wrong, just saying I’ve done it both ways and I find his method quicker, more streamlined, and ultimately less expensive.

[Mad Charlie]

Works the same for me also.