Load Development

[lordpaxman]

It may help those that don’t know what OCW is to read this first:
http://optimalchargeweight.embarqspace.com/
Then perhaps you’ll have an idea of what the OP is doing.
To the OP, the increments of charge weight you used are more like a ladder than Newberry’s OCW. Still, you’re looking for the charge weight where groups centers vary the least. @ruger15151 called it with the first two.
With OCW, you want to get the charge weight first, then do a lands test. Good luck!

 

[Demi-human]

I found the link to explain what it does, without explaining how it’s done. An infomercial.

Would not the node be found with ever increasing charges?

And you say the group centers, not the individual shots?

Is there any other links for this process you know of?
I’ve read about it in the past, but like I told Jim, I don’t do it like this often. I’m looking for a better understanding, maybe I’ve conflated some techniques.
Like Chamokaneman, the increasingly rarer times I get to go out, I don’t want to be doing it wrong.


(Or I can put my glasses on and see the menu button at the top of the page, with instructions and everything...
Sorry.)

 

[AJC1]

So this was an initial test as mentioned earlier with spreads to far appart to really be definitive. I picked the group that looked smallest with the least vertical, not close to a final call but an area that I felt would be worth investigating. Some cartridges have multiple speed plateaus and some only one or two narrow ones. This type of testing really likes a cronograph. Sd of the loads can tell you a lot.

 

[JFrank]

Sooooo—-
What’s the synopsis here fellas???

 

[chamokaneman]

Sooooo—-
What’s the synopsis here fellas???

Well for me, I think I'm gonna assume that the charge between my #1 and #2 is a "node" and probably mess with seating distances a little bit at that charge. I'm also going to take a second look at my brass to make double sure I'm not having any pressure issues and shoot a #6 group at .2 heavier than #5 to see what it does. If it's really similar to #5 I'm explore that too.

 

[climbnjump]

First time I've ever tried develop a load using what I think is a form of OCW and I'm a pretty novice reloader.

#1). You are a novice reloader.

My heaviest group (group 5) has 46.7 grains which is just .2 over what the Hornady maximum call for with no signs of trouble.

#2). Group #5 is 0.2 gr over Hornady max.

I'm also going to take a second look at my brass to make double sure I'm not having any pressure issues and shoot a #6 group at .2 heavier than #5 to see what it does

#3). Now you're going to try 0.4 gr over Hornady max.

Just stop.

Yes, as someone else stated in an earlier post on this thread, people do sometimes load over max recommended loads. You can find more than a few threads on this forum discussing that issue.

But see #1 above.

As a novice, the game isn't to see how far you can go over max before you run into trouble.

The game is to develop an accurate and SAFE load. In many cases, the most accurate load will be found some distance under the max load anyway.

Besides, with that combination of powder and bullet, you are probably looking at less that another 20 fps anyway. That's not a delta that will make a difference to the antelope.

It would be good to get some experience under your belt before you start coloring outside the lines.

 

[lordpaxman]

I found the link to explain what it does, without explaining how it’s done. An infomercial

I almost did something I really detest when others do it... Not read the entire post first..... And saw at the end you did find additional links! For others who might jump the gun, there are links to directions and scenarios, for example:

http://optimalchargeweight.embarqspace.com/ocw-instructions/4529817134

Now, I’m just the messenger, don’t shoot me. I’ve tried this method and had some success, but others on the forum here who have more PR experience have said you should shoot the groups at 300 yards for more meaningful results. There are also other load development methods that are favored over this one.
My understanding of OCW is you read the groups to find the center to center variations and when that is minimized, you have an accuracy node. That is the POI is less sensitive to charge weight variations and barrel harmonics. The lands test after that should optimize group size. It does not necessarily mean it’s a velocity plateau, although I’ve found this to be the case as well.
My experience with chrono numbers on rifle loads is that unless you’re lucky and found a good case/powder/primer/bullet combination, SD numbers don’t get really good until you do a lot of case prep and precision reloading with precision shooting. Good luck!

 

[JFrank]

View attachment 931958
This chart reflects an 80 grain projectile

 

[Nature Boy]

You should shoot ladder tests at 300 yards or greater

You should shoot OCW tests at 100.

For either test to provide meaningful data, you’ve got to have some degree of control over your inputs. Your loading technique and rifle mechanics must be at a level where that they don’t add noise the results.

In other words, getting to the most accurate load is an exercise in isolating variables. If you’re adding variation to your loads because your brass prep is weak, or your rifle isn’t stable on the bench affecting your shot to shot repeatability, then you’re just spinning your wheels and wasting time and components.

 

[entropy]

In other words, getting to the most accurate load is an exercise in isolating variables. If you’re adding variation to your loads because your brass prep is weak, or your rifle isn’t stable on the bench affecting your shot to shot repeatability, then you’re just spinning your wheels and wasting time and components

Well said.

 

[PecosRiverM]

My question is it a typo or why use RL 19 for .243 ??? Isn't RL 15 or 17 better??

Edit: After thinking maybe that's all the OP has to work with. I don't see a post delete button.
Sorry

 

[climbnjump]

My question is it a typo or why use RL 19 for .243 ??? Isn't RL 15 or 17 better??

Edit: After thinking maybe that's all the OP has to work with. I don't see a post delete button.
Sorry

Legitimate question, I think.

Depending on the application in .243, RL19 can work very well. I use it for 105 and 108 gr bullets in a fast twist barrel for long range shooting. I have also tried RL16, 17, 22 and 26 (but not RL15) in those applications and for ME in MY rifle, RL19 gives the best accuracy. If velocity only was what counts, then that would be RL26. (But if we expand the discussion beyond Alliant powders, H1000 and H4831SC work almost as well as RL19 for me.)

But I also tried to develop a hunting load using a 95 gr Berger. And for that, RL19 wasn't very good, but RL16 was great.

But having said all of that, I agree that for the OP's 80 gr bullet, RL19 probably wouldn't be my first choice. But if it was the only powder I had, I'd certainly use it.

So, like a lot of things, it just depends...

 

[JFrank]

You won’t know until you try, Nosler list RL-19 for a slightly heavier bullet in a 243

 

[Demi-human]

So, like a lot of things, it just depends...

It says to use the slowest appropriate powder for the application during the OCW test.
I don’t know why it wouldn’t have the same result with whichever powder is chosen, however. If it is a truly effective way to tune a rifle, it aught to work with whatever one has.

 

[JFrank]

There are certainly other ways to develop quality ammunition.
OCW was topic so I stayed there.

 

[Nature Boy]

I’d like to clarify my comment above because after reading it again I think I came across as dismissive to the OP’s efforts.

As long as I can come away from a range session having learned something then the effort is worthwhile.

 

[Demi-human]

As long as I can come away from a range session instead of having done the chores list then the effort is worthwhile.

I fish, to have not worked.

 

[Varminterror]

Sooooo—-
What’s the synopsis here fellas???

I just stumbled into this thread this afternoon, so you’re clearly not asking for my reiteration of input, but personally, based on the disparity of group size in the shared target picture, I would not draw any conclusions at all, other than to conclude that particular test had some distinct flaw. Statistically, I can’t support that groups with that much disparity are representative of their respective sets, such the scribed centroids do not accurately represent valid Centers for a normal distribution.

In other words; the potential conclusions which should have resulted from this experiment were completely lost in the (statistical) noise.

 

[Varminterror]

Something I will also mention: I have not personally had as much luck with OCW tests at 100 yards as I do at 300, or better, 600. If I shoot OCW, Ladder, and Satterlee tests at 100 yards, I do not expect them to result in 3 perfectly aligned conclusions. If performed at 600, I DO expect the results to align.

But again, if my group sizes are this much larger than the dispersion between adjacent charges, ESPECIALLY with such a low round count used in the test, I would not draw any conclusions from the test. Well, admittedly maybe I would conclude these results indicate something is terribly wrong with the rifle, the shooter, or with the powder and bullet combination.

I MIGHT be convinced to repeat it to determine whether it were a fluke or not, but most likely, my response to that test would be similar to accidentally walking into a ladies restroom at a new restaurant: instant realization I’m somewhere I should not be and need to leave immediately, as well as permanent impression I should remember to never again return. I would NOT be motivated to waste any time looking around, trying decide which stall looked best.

 

[Nature Boy]

I MIGHT be convinced to repeat it to determine whether it were a fluke or not, but most likely, my response to that test would be similar to accidentally walking into a ladies restroom at a new restaurant: instant realization I’m somewhere I should not be and need to leave immediately, as well as permanent impression I should remember to never again return. I would NOT be motivated to waste any time looking around, trying decide which stall looked best.

Or, try to pull it off with a "I meant to do that"

 

[JFrank]

Something I will also mention: I have not personally had as much luck with OCW tests at 100 yards as I do at 300, or better, 600. If I shoot OCW, Ladder, and Satterlee tests at 100 yards, I do not expect them to result in 3 perfectly aligned conclusions. If performed at 600, I DO expect the results to align.

But again, if my group sizes are this much larger than the dispersion between adjacent charges, ESPECIALLY with such a low round count used in the test, I would not draw any conclusions from the test. Well, admittedly maybe I would conclude these results indicate something is terribly wrong with the rifle, the shooter, or with the powder and bullet combination.

I MIGHT be convinced to repeat it to determine whether it were a fluke or not, but most likely, my response to that test would be similar to accidentally walking into a ladies restroom at a new restaurant: instant realization I’m somewhere I should not be and need to leave immediately, as well as permanent impression I should remember to never again return. I would NOT be motivated to waste any time looking around, trying decide which stall looked best.

I Probably still have my very first targets from testing loads that look similar. One thing I’ve learned is I’m still learning