I won't steal his thunder here, but one of my buddies has a pet theory about load development.

Forgetting the mechanics of adding the components to each other for a moment, what thought process do you go through when starting the devlopment of a new load? What are your reference points?

Me? Well, I'm a beginner at this so I start from a number of different places - here's a specific bullet I want to use, there's a powder which the manuals seem to favour, and so on. I stop when I reach a point where I'm happy with the results, or when it becomes obvious that things ain't going too well, as with too heavy a bullet.

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Assuming that I am looking for the load that will give the highest velocity with acceptable accuracy (not always the case, sometimes I am looking for good accuracy at a specific reduced velocity) I go through all the manuals and tally up the powders that show the highest velocity for the bullet weight I want.

I note the 2 or three powders with the most "votes", especially those I already have a can of.

Then, I take a Post-it pad and make up a cheat sheet. I head it with the caliber, bullet weight and powder, then have a line for each manual that lists that powder showing the starting charge given, maximum charge given, and maximum velocity specified, as well as the data source.

I take a look at the figures and if there are a lot of listings (e.g., .30-06/180-gr. with IMR 4350) I throw out a couple of the lower starting charges, which are usually those from manuals such as Hornady or Sierra which list loads according to the powder charge that will achieve each given velocity increment. My thought is that if I am looking to achieve 2700 fps there is little need to start developing from a load that will give 2300.

Then, I pick a reasonable starting load, load 5 rounds, and turn up the powder charge 1 gr. at a time until I get to a level that shows as maximum in one or more of the manuals. I figure I may be able to go to another manual's maximum but if I can't, it'll just mean more bullets to pull.

I go to the range, shoot, and note the results. If I run out of my top load before showing any pressure signs or reaching anticipated velocities, I go home and load a few more increments. I won't go (so far) to the highest maximum load--but so far my rifles rarely achieve the specified velocities anyway!

Hope this is helpful.

If it is a bullet weight or caliber I have never used before, I START with the Alliant Powder manual and see if what I want to shoot is listed.

Alliant's Manual is the best there is for true performance of a given load.

They have a max loading listed.

Start 2-3 grains below and work from there.

If what I want to shoot is not listed, then I go to a Nosler, Hornady or Speer book and see what they have to say.

ALWAYS start a bit below max and work up.

I then will load series of rounds with 1 gr increment increases.

I will fire them over the Chrony, and see how velocities compare to the data.

Somewhere, it will soon tell you what direction to go.

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May I be half the man my dog thinks I am.

My development works much the same way. Start with the bullet you want to shoot. Match it with a powder. Run it up to the velocity I'm after. Fine tune with the seating depth. Crimp with a Lee crimp die, if I'm not happy with the final result.

I'm always surprised how much stock some shooters are willing to put in one three shot group. To get a good idea of the accuracy and consistency, it takes quite a few 3 shot groups of each load.

Anyway, that's what I do. Dutch.

I'm new at this but wouldn't it be best to start with finding the OAL of the gun and seating bullets accordingly with whatever powder on hand to find out what lenght shoots best? I mean if a gun shoots best at a given cartridge lenght wouldn't that cartridge lenght be the best for any given powder?

We have found the quickest way through a load development is to forget about accuracy and work up the speed first. We do this at the longest col the rifle will deal with. Once the speed is established, we work the bullet back into the case and shoot groups at each col to find the sweet spot the rifle likes. It saves time and components if you work one parameter at a time.

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Gerard Schultz
GS Custom Bullets

If I didn't know better, I'd think my mate and Gerard had been sharing ideas - his view is that the secret of success lies in finding the velocity which matches the barrel's harmonic frequency - I guess this is what Gerard eludes to as the sweet spot?

Here's my next question - how to speed up the trial and error process of finding that "magic" velocity? It's bound to vary between rifles and I can't help but think there's got to be a more efficient approach than working up loads of differing velocities and watching for the point at which improvement comes.

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Pete,
We have found that col has a bigger effect than speed on group size. That is why we simply work for a desired speed and after that, look for the match in the harmonics of the barrel with the seating depth of the bullet in the case. This is basically the mechanism behind the BOSS tuning system. They say you load what speed and col works for you. and then tune the harmonics with the BOSS.

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Gerard Schultz
GS Custom Bullets

'scuse me if I'm being thick, but isn't the BOSS system just a moveable damper which you move up and down the barrel?

Would you say that the BOSS always brings about improvement in barrel performance in any barrel, and isn't possible to acheive harmonic compatibility twixt round and barrel without sticking a weight on the muzzle?

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Pete,
The BOSS system tunes the harmonics of the barrel by moving the weight forwards or backwards on the muzzle. The same can be achieved by moving the bullet closer to the rifling or deeper into the case. In both cases the object of the excercise is to get the bullet unplugging from the muzzle when the muzzle is at a turning point in the cycle of vibration. By way of example; let's say the muzzle describes a figure 8 in the cycle. You would want the bullet to release when the muzzle is at the bottom or top of the 8 and not somewhere in the crossover point. I have a printable load development chart which is quite useful at http://skyboom.com/gscustom/hvloadguide.html below the Load Guidelines. It saves time and components and can be used with any brand of bullets.

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Gerard Schultz
GS Custom Bullets

Okay, so what factors do you use to determine "desired speed"?

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Pete,
Visit some powder websites and check the starting and maximum speeds listed with their loads for the weight and type (jacketed lead, conventional monometal, solid shank etc) bullet you are using. Use a chronograph and do not exceed the general maximum speed that you researched. You decide if you want to run at the top end or down the middle. Maximum pressure reduces case life and makes more recoil. Sort of like add salt to taste, you decide beforehand what speed you want and work up to it.

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Gerard Schultz
GS Custom Bullets

Gerard,

Thanks - that just what I'm doing...you had me wondering if there was a different approach, or perhaps a different factor to take account of. As it is, I've selected "desired speed" as the one where my groups are smallest.

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