The Evolution of Load Development

The Evolution of Load Development:

What is your goal? Is your intent to reproduce your favorite factory load for your hunting rifle, or is it to develop a load for a new rifle of the long range persuasion? This represents opposite ends of the spectrum and for sure will dictate how much you do, or don’t do, to achieve your goal. With that in mind, the purpose of this information is to look at generalizations and methods that can lead to the same results.

Focusing on long range capable loading, and not shooting equipment, it should be noted that the quality of components you use will have a direct impact on your finished product. The brass you decide to use will be of utmost importance. Let us assume everyone knows how to uniform their brass, and everyone knows skipping steps will lead to less return on your effort. Fully uniformed brass (fire forming included) will give the best results, period.

Choosing a powder or powders to test comes with lots of options. Reloading manuals can give you a great place to start. Burn rates particular to caliber and bullet weight deserve attention. Burn rates generally have a fast end and a slow end recommendation for each caliber and bullet weight. They all come with a recommended maximum, and some even give a starting load. Let’s assume everyone knows ignition of the powder results in a gas that causes pressure and creates harmonics and results in velocity. Being ever cautious of perceived signs of high pressure, and monitoring resulting velocities will give you data for comparison from powder to powder.

Besides charge weight, other things you control that can influence pressure include (but are not limited to), seating depth and neck tension. The result of seating a bullet against the lands, as well as seating deep into the powder column must be understood. Neck tension can be addressed in a couple of ways, like choosing to turn necks for uniformity, and using a bushing-type die.

The quest for accuracy that must be accompanied by low extreme spreads and standard deviation varies, as we all know, from rifle to rifle for many reasons. As combustion pressure relates to harmonics, harmonics become essential in the accuracy equation as the harmonics are broadcast through the delivery system, the barrel.

I am fairly certain there exists equipment and computer-generated graphs that can map barrel harmonics. As to the affordable availability of using this technology, or being able to have personal tests done by others, I have no clue. I mention this because I quite believe if powder tests could be accompanied by harmonic maps, we would see a whole new level of accuracy to include low es and sd.

Now, finding that best load for your rifle. The purpose of this writing is to address some false generalizations, like it only takes 10 rounds to develop a load. 10 round ladder test and I’m done. This information is best used by those who already have collected obscene amounts of data and can tell you off the top of their heads what powder and how much. A 10 round ladder test and there’s no need to run up your round count on your barrel, and then at a later point mention they don’t even try to develop until after they have a hundred rounds down the bore to fire form the brass. Round count is round count . . .you now have 110 rounds down your tube and still need to do more testing for final load. 10 round ladder gets you very close IF you already know and anticipate results. Then there’s seating depth and es/sd, but you already have a good idea how that’s going to turn out as you have previously tested that and already have that data.

We recently did load development on a new rifle. We started with new brass, pulled a seating depth based on previous experience, and started loading in increments of two tenths. We started with a powder we are confident with.

Once we started shooting, everything was on the Lab Radar. We shot 3 shot groups from start to finish so we would have data to identify flat spots and nodes, the same as you do on a ladder test. We were able to see how the groups correlated to the flat spots to determine nodes. As expected, we had one low and one high node within our range of pressure. So in essence, we combined merely fire forming brass, with graphing nodes and flat spots.

By the time we approached 100 rounds, we hit the “barrel speed up” point which is another reason folks fire form brass (two birds with one stone, fire formed and speed up done). Fire formed brass gives better es/sd than new brass, so rightly so, it’s necessary.

Once we hit the speed up and confirmed it with a couple more groups, we did the math and reduced loads accordingly to bring velocity back down to the node we desired. Then we confirmed our velocity and compared the group to see it was no different than the group of the same velocity at the higher charge weight before barrel speed up.

Once this was complete, we took 3 other powders to the same velocity nodes to compare them to our best groups. Even though I’ve recently read people state they can get any powder to shoot well, so long as it’s at the same velocity node . . . well for us, that is simply not the case. It might get you close, but it’s not exact. That takes me back to harmonics mapping . . . thinking different burn rates even at the same velocity may print different harmonic maps.

We shot a final 5 shot, .35 group single digit es to wrap up this project in 112 rounds and have usable data to support later projects of the same caliber. My thought? If you need to fire form your brass before you start development, why not take the data from that exercise. Unless of course you already have that data, but 100 rounds fire formed and 10 round ladder test vs. our 112 rounds to complete development is in my mind a wash. Obviously there is more than one way to get this done netting the same results.

R. Mckinnon

Recent load development with a Benchmark barrel 7mm Rem Mag with a Berger 175 EL, Reloader powder

Recent load development with a Benchmark barrel 7mm Rem Mag with a Berger 175 EL, Reloader powder

GRS Berserk Stock

GRS Berserk Stock

At the bench, the Berserk provided improved groups over the Savage factory accu-stock. I’m certain this can be explained by way of proper fit to the shooter. If you have never shot an adjustable stock, then you don’t really know what a good fit is. Rifle stocks, like socks, should not be lumped into a one size fits most category. Since we have been shooting a variety of adjustable options the last few years, we can hardly get comfortable behind a regular old stock anymore.

Rifle Dies

Rifle Dies

Based on Team B2B Precisions personal testing and the account of our RPR .243 Load Development article at Long Range Hunting on line magazine, we can say without a doubt, we experienced measurable gains in precision by full uniforming of our brass to include neck turning and using bushing dies. When you enter a repeatable factor such as neck tension to your process, you are also affecting velocity and pressure. Knowing that each and every bullet can be released under the same pressure and obtain very similar velocity gives you the confidence that your collected data will give you first shot hits at very extended ranges.

To Reload or Not to Reload

Have you ever stood in front of the mirror and asked yourself . . . “should I reload my own ammo”?  Well, me either.  But I have asked myself if it’s really worth it to reload ammunition.  

Trying to explain worth, one has to consider the money side of reloading.  How much is it going to cost.  Next, understanding just what kind of accuracy improvements you can expect to see from loading your own ammo.

Before I talk about scopes, I will backpedal just a bit to include some more info about box rifles...

Before I talk about scopes, I will backpedal just a bit to include some more info about box rifles; the Savage GRS is a promotional item and is in limited supply until later in the summer.

I would also like to add that yes, Remingtons in certain models are also good.

I will explain more later about what distinguishes the hunting rifle from a play rifle.

The Origin of This Blog

The following information first appeared on Len Backus' Long Range Hunting Online Magazine Forum on 01/28/2016.  JDMecomber, Manager for B2B Precision first started publishing data and findings from his research on this forum under the Load Development Ruger Precision Rifle .243 thread.  This thread has received a lot of attention in the long range community, and we are going to continue posting further developments on this blog as well.

This blog will reflect all the prior posts from B2B staff and all future posts regarding the long range data and load developments.