OCW Reloading
Dan Newberry's OCW Load Development System
"Optimal Charge Weight" and the acronym OCW as regards the reloading of metallic firearm cartridges are the intellectual property of Dan Newberry. If using these terms in your own writings, please refer your readers to this webpage for concept clarification. Thanks!
What is an Optimal Charge Weight load?
With any given bullet and powder combination, there will be a specific amount of that powder which will cause the bullet to exit the muzzle at the "friendliest" portion of the vibration cycle. This does not necessarily correspond with the tightest velocity figures, however. Many load recipes have over the years become the "go to" recipes for trying out a new rifle. If your rifle fails to shoot one of these "tried and true" recipes well, you may well have a rifle integrity problem. Consider the Federal Gold Medal Match .308 Winchester ammo. How can one recipe shoot so well in so many rifles? That's what we're after in the OCW load--a load recipe so stable and predictable that it does indeed rise above, and to some extent disprove the "all rifles are different" adage of lore...
If you subscribe to the philosophy that "all rifles are different," and therefore need individual loads tailored to accommodate their idiosyncrasies, how do you explain the near universal MOA performance of factory loads such as the Federal GMM?
Universally good recipes do exist. Upon realizing this, my questions have been "How do such recipes work?" and "How can I identify such a recipe?"
Theories vary as to why the OCW load works. Chris Long, a friend and engineer has the most plausible idea as to why OCW loads work. He says that the acoustic shock wave which runs end-to-end down the barrel, repeating at around 18,000 feet per second, will disturb accuracy when it is near the muzzle. Therefore, the idea is to cause the bullet to exit the muzzle when the shock wave is well away from the muzzle, back toward the chamber. Finding a particular powder charge that will allow this is what OCW reloading is all about.
An example OCW load development follows:
The rifle was my old Remington 788, a 243 Winchester. The bullet was the Sierra 60 grain HP, and the powder used was IMR 3031. (IMR 3031 is an excellent powder for the .243 Winchester with 80 grain and lighter bullets, but you couldn't prove it by the majority of load data manuals--most of them simply overlook it!) Primers were the CCI 200's, and brass was all twice fired Winchester.
In checking the available load data sources, I noted that 39 to 41 grains of IMR 3031 was the suggested max charge zone for IMR 3031 with 60 grain bullets in the .243. I have found that the best loads for all of my own rifles have been loads that were at or near listed maximums, but I do test about 5 percent below for pressure signs, then work up.
I began with three rounds each of five different charges, graduating in .3 grain increments. The tested charges were 39.2, 39.5, 39.8, 40.1, and 40.4 grains.
I cleaned the rifle, and shot two fouling shots using IMR 3031 at 39.2 grains, and allowed two minutes for it to cool. I had five targets posted at 100 yards, one target for each charge variation.
I shot one round of the 39.2 grain charge at target 1, allowed a minute or so for cooling, and then fired one shot of the 39.5 grain charge at target 2, cooled, one shot of the 39.8 grain charge at target 3, cooled, you get the idea...
This is basically a "round robin" system of grouping each charge, which precludes disadvantaging late groups due to fouling, or heat build up.
When finished, I had three shots on each of the five targets, BUT (!)... I don't look for the tightest group of the five and call that my load.
Here's what I do instead, and I'll explain why later: I look for the three groups of the five that come the closest to hitting the target in the same position. I noted that in this case, the three center groups were the ones which happened to hit the same general POI, (all within about 3/4") with the 39.2 grain group hitting low and left from that common POI by an inch. The 40.4 grain charge, in addition to moving high and right of the common POI for the three center charges, opened up in size to about 7/8". The 39.2 grain charge shot wasn't a bad group, but as I said, it wasn't near the common POI that the 39.5, 39.8, and 40.1 charges shared.
So I concluded that the best charge for this application was 39.8 grains of IMR 3031. This was the charge that would allow 39.5 grain charges and 40.1 grain charges to group right with it.
Why would I want that?
Well, variations in brass cases, powder lots, outside temperature--and other things can cause your load to increase or decrease in pressure. With the OCW load, you're covered for a significant amount of pressure differences that may come into play. If I'd gone with the 39.2 grain charge, a *slight* rise in pressure, brought on by an odd brass case or a hot day, etc., would have resulted in a 1 MOA deviation high and right of my POA. This is one of the reasons you may be getting occasional flyers with your handloads--the load recipe is not actually on an OCW node.
I shot a 1.5" group at 300 yards with my .308 load with the 168 grain Sierra Matchking using one shot of 43.3 grains IMR 4895, one of 43.6 grains, and the third shot in the 1.5" group was charged with 43.9 grains. (The OCW being 43.6 grains, of course). This proves the resilience of the 43.6 grain charge (in Winchester brass, by the way).
Interpreting the results is key to getting the right load recipe. Rarely do we require more than 20 shots from start to finish. Again, this system saves time and money, and gets you the best load for your rifle in the process. See the video below for a better understanding of the process.
If you would like my help developing your OCW handload, we can set up the plan over the phone for a consultation fee of 50 dollars (way less than a pound of powder these days). You'll save a lot of money, and a lot of time. I'll stay with you via phone and email until we get "the load" for your rifle. To book a consultation, click on the button below.
OCW CONSULTATION
A one-on-one consultation with Dan Newberry for the purposes of developing an accurate, repeatable load for your rifle. Be sure to email me at danielnewberry@gmail.com once you've purchased the consultation, and we'll set up the first phone call.
Additional Info...
Please read...
I'm Dan Newberry, the designer of the Optimal Charge Weight method of handload development. If you are unfamiliar with my work, you can google my name and "OCW" or just "reloading" and you'll find hundreds of articles and forum threads pertaining to my reloading system. My system allows you to find "the" load you're looking for in as few as 20 shots. And unlike the traditional ladder test you may have heard of, my system identifies nodes of inaccuracy along the powder charge continuum--the source of many "flyers."
Because of increasing demand (likely driven by the rising cost of reloading components), I'm now offering a one-on-one consulting service to personally assist you during your OCW load development process. Are you tired of getting those inexplicable "flyers" in your groups when you know that you didn't do anything wrong? Have you done ladder tests ad nauseum and you still haven't found a consistent load recipe? Is your load recipe so sensitive to minor changes that even a primer swap blows your accuracy? Would you like to learn how to make your cold, clean bore shot touch the rest of the group? Then keep reading...
I've counseled hundreds of shooters over the years by email and internet forums to help them find "the" load for their rifle and application. While these encounters have been quite successful (don't take my word for it, google search my name and "OCW" and see for yourself), written interaction does have its limitations. In literally dozens of cases I can remember finding out that a handloader had overlooked obvious hinderances to accuracy--and this we sometimes learned only after he'd spent a couple hundred bucks on components and range trips. Although many folks have become quite profficient at interpreting OCW targets, I still see that many are not. This means that simply shooting an OCW test is only part of the accuracy equation--you also need to properly interpret the data. Another concern is that we see folks adjusting the OCW process and "improving" it, sometimes by shooting at longer ranges than are prescribed, and/or by failing to shoot in round-robin fashion, or adding shots or taking shots away... All of these steps will work against you in the end.
Why hire a consultant?
First and foremost, you will save money. Very likely lots of money. If you'll be honest with yourself and carefully add up the cost of bullets and powder and primers and worn out brass and trips to the shooting range, you might be surprised just how much that magical load you finally arrived at has actually cost you. In a recent case, a man who had spent over 300 dollars chasing an accurate load for his .243 Winchester was led to a sub MOA load recipe in less than 20 shots.
I have compiled a database of handload information over the years that will allow me to steer you toward good combinations for your intended purpose--and away from bad ones. This alone will save you a considerable amount of money right from the start. Ballistics techs at the major bullet and powder makers don't always know what combinations work best. And like most handloaders, they tend to follow the age old "hunt and peck" method of load development, so any ideas you do get will have come from such processes.
Finally, there are many basics that some of us forget when it comes to shooting accurately. It simply takes too long to go over each and every one of these issues when we're interacting by email and forum posts alone. Often, we need phone consultation to really get to the bottom of what is going on.
If you choose to enlist my help for your load development endeavor, you will avail yourself of the following:
Absolute privacy. Your name and information will not be shared by me for any reason unless you specifically grant me permission to share your target photos and/or testimony.
Personal contact by phone (if requested) for the initial consultation, and for a follow up if necessary. In our initial conversation we'll discuss your rifle and scope combo, the purpose which you're using the rifle and load for, what components you may already have on hand which could work for you, and a sensible accuracy goal. In a follow up phone conversation (and/or email), we will discuss your targets. We'll interpret the data, and consider seating depth adjustments that may improve your accuracy even more.
A load that works. We will not stop until you're happy with the load you have. And during the process, you will learn much that will help you with other loads in the future.
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The cost of my service is a very modest 50 dollars, which you can pay by credit card or paypal. That's less than a pound of powder and a box of bullets. And if you consider your time worth anything at all, factor that in as well. You have my promise that you will save time and money, and on top of that you'll arrive at a load recipe that will get all of the potential from your rifle.
If you have any questions, or if you are interested in my services, email me----> danielnewberry@gmail.com
an alternate email is bangsteel@gmail.com
VERY IMPORTANT! There is no way we can teach you proper rifle handling technique from over the phone. If you're not absolutely sure that you are able to shoot tight groups with the rifle (assuming all else is in order) it would be best to avoid a consulting session until such time as you have your shooting technique down well. Quite often, we have clients whose targets show evidence of bad recoil control and/or trigger-jerk (lateral and diagonal flyers, both high and low), and unfortunately we can't fix that over the phone. You'll need to work on proper shooting technique until you have things under control. Shooting a high-powered rifle accurately is not as easy as you may imagine, and there are countless hunters and shooters who spend a lifetime doing it wrong.
You will want to test your rifle with a box of quality ammo to be sure that the rifle and shooter are up to the accuracy task BEFORE you open a consulting session. Some ammunition that we know works well include Hornady American Whitetail, Fusion (Federal), and Federal Power-shok. Normally, Winchester Super-X (silver box) is a reasonably accurate factory load also. Any of Hornady's Superformance ammunitions have been proven to work well. If you're getting respectable results from such ammo, then you and your rifle are likely working just fine; we can then begin a consultation for the handload you plan to work on. :)
Please note this list of the most common problems shooters have with conducting a good OCW load test:
1) Electronic scales of low quality will drift from zero during the loading process, especially with a cell phone nearby. Use a quality beam scale, or a proven quality electronic scale.
2) Shooting from wobbly portable shooting tables. Shoot prone off a bipod and solid rear sandbag, or use a concrete or similar permanent shooting bench. Portable tables will double your group size in most cases.
3) Insufficient knowledge of scope parallax adjustment and sight picture, or problems with consistent cheek weld for each shot, proper trigger pull, and recoil control--all of this can conspire to ruin your groups.
4) Shooting a bullet which is seating depth sensitive is rarely a good idea. Companies which have historically produced seating depth sensitive bullets have by now lost enough market share that they're making better bullets which are less prone to being damaged at inopportune seating depths.
5) The client should realize that groups which exceed 2 MOA at 100 yards are *not* caused by the load recipe which is using a quality, well designed bullet. Even the worst 100 yard "scatter node" groups should not exceed 1.5 MOA in an accurate rifle which is being properly handled.
6) Light neck tension from bushing dies with less than .003" of neck tension rarely outperform Full Length sized brass in the same recipe.
7) Bad target design. Be sure to use a target which allows you to "lock" your cross-hairs into the center. Here is an OCW target designed by AC Lakey which we've used for years. CLICK HERE
The following is the procedure for submitting your target photos during the consulting:
--> RE-READ the above seven points!!
--> Keep all groups on the SAME target page. I can't evaluate the POI shifts if you have a different photo file for each charge weight being tested. You may shoot your sighter/foulers on a separate page if you like, but for the OCW test charges, I need them on the same page.
--> You MUST clearly mark the targets with a dark marker (Sharpie) with powder charges designating which group is which. Include in the notes ON THE TARGET anything pertinent (called flyers, pressure signs, etc.)... it is also helpful to mark which shot in each group was shot 1, 2, or 3.
--> I don't need any excel spread sheet info, and I don't need colorful, triangulated drawings (On-Target software stuff, for instance) of the goings on--just the target, with the data written on it.
--> You can scan the target page, or simply take a good photo of it and attach to your email. You can include some comments in the email which you feel may be pertinent to the interpretation of your results.
To purchase an OCW handload consultation, please go to the OCW Reloading page at our BangSteel website. BangSteel.com Thank you!