Verifying and finishing loads

shooter72

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Jan 19, 2016
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When working up loads how crazy does everyone get at 100?
How much effort in tuning loads at 1000+?
How many shots per group do you like to have?

Just curious how everyone else does things. I just finished up my 300WSM and the smallest 100 yard group didn't have the best "shape" and didn't preform the best out long. Nothing new for me to see this but made me ask what everyone else likes.
 
"likes"? I like 1/8" three shots at 100 yards. But settle for five in 5/8" repeatable at 100.

After I finish a load I try different primers just to make sure it is as good as it going to be.
 
If it groups under an inch at 100 and you've got 20fps SD's you're fine for 1000.

For my own purposes as a competitive shooter: I require my match loads to print under .7"MOA, .5" or smaller is better and I'll usually go till I find a load that's not super sensitive and delivers that .5MOA 5-shot group. My SD's, I require them to be under 20fps and under 10fps is better. Once I have a load that makes my requirements at 100, it'll make it at 1000.

I never would "tune" a load for 1000 because it should not behave markedly differently at 1000 than it does at 100 if it's still fully supersonic. I would tune the shooter if there's a big difference between how it does at 100 and how it does at 1000 (in terms of angular measurements).

Here you can see exactly how Coach and I did our last load dev cycle. This is bascially how we do it every time.
https://www.longrangehunting.com/threads/6xc-load-testing-analysis-n550-rl23-imr-4166-h4350.213871/
 
It depends on the cartridge for me. If it's a 300 wsm I shoot 3 shot groups and if it's a 223 I shoot 5 shot groups.
Most of my loading data comes from a chrono though. Even if your grouping 3/8 inch groups at 100 yards, if the standard deviation of your chronoed rounds has a large spread your groups are going to open up at extended ranges. I've had my best groups at 100 yds be some of my worst 600 yard groups. Use a Chronograph, it takes some guess work out of it.
 
always curious how everyone else does it.

Now I always tweak or tune at LONG range as 100 yards can fool you for distance IMHO.
I have some groups that shoot in the 1's and 2's with SD under 10fps that string or don't repeat as well as I would like at 1000.
My current gun I just finished the 100 yard group has beautiful shape but not nearly as tight as I would usually like the 10 shot ES was 12fps though and it shot under 3" at 1050. I am going back out this weekend to see if the distance repeats again. if it does I am done with it. No sense in chasing bullet holes in the zero's unless your shooting point blank.
 

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If your using a chronograph then doing your load development at 100 maybe fine if your not using one it's a completely diffrent story. I've had many excellent 100yd loads shoot like crap at distance because I didn't know my SD's. The technical advances in optics, machining, chronograph's, ballistic software and bullets/ammo have made long range much easier to accomplish in the last 10-15 years.
 
I don't do anything crazy at 100 (depending on who you ask). When I start working up a new load, I usually load up some multiple of what divides out evenly when shooting 4 shot groups (my way of striking a compromise between 3 and 5 shot groups). For example, if I have 23 cases, I'll load up 3 "check charges" which also serve as "foulers" starting at the lowest published charge and going up in .5 grain increments. My actual ladder will start somewhere in the low to medium band of the published range and I'll shoot five 4 shot groups at each increasing rung (.2 to .3 grain increments) of the ladder up to max. It usually works quite nicely for me and I find a node/nodes pretty quick. It may take me a couple of sessions to hone in on the charge I want. Then I load everything uniform, go back and chrono it to check SD/ES and test it out out to 300 yards. If I'm under a minute at 300 and have less than 1/2 MOA vertical dispersion at that distance, I call it a day because it's more than sufficient for any critter I'm gonna shoot at around here.
 
I find myself hardly using 100y at all anymore. I shoot my ladder tests at 300 as well as my tuning loads. If you have a good shooter, there may not be enough variations at 100 to really decide. It's easier to see at longer distances. All mentioned above applies, looking for low ES/SD. If you're trying for 1moa, stop there. If you going for 1/2 moa, keep working on it.
 
I do load development at 200 yards. 3 shot groups with magnums, 5 shot with varmint rounds. Run everything over the chrono and look for ES less than 20 and SD less than 10. The last load I developed for my .300wm hadban SD of 8.5 and it shot a 1.8" group at 400 yards with less than .25moa vertical dispersion
 
I cheat....I start out begging for other shooters "pet" loads, look for a pattern, pick out the most popular and load that load and a couple grains either side.

I cant see wearing out a barrel doing 100 shot ladder test, But I am also satisfied with "great" not looking for the " wholly grail" load

IMO, too many "conditions" make these tests impossible, re; HUMAN factor. Lock the rifle in some unmovable , DEAD solid rest, NO wind, yes, maybe.

many rifles arent capable of shooting groups the owner expects, sorry guys but its true

Its pretty much a mental thing. Find a good load, stick with it

NOW, if you got deep pockets an TONs of time, buy 3-4 different powder, bullets, brass, etc and knock your socks off. You may not get anything out of it but, he77, its shooting
 
One thing, unless you have your rifle mechanically held by a vise or other, I would open up your sample size to 5 shot groups, unless you are absolutely sure of your level of pull from shot to shot, and the great shooters can do that and get way with a 3 shot test group.
 
Extream spred is the difference between the highest velocity and the lowest. Standard deviation is a mathematical formula that measures / averages the spred between the number of velocities that are measured.
 
I was told SD determines the next shot, with 90% certainty, within that number of your average velocity. For example if you have 3000 feet per second with an SD of 10, the next shot will be somewhere between 2,990 and 3,010 feet per second.
 
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