Dan Newberry's Optimal Charge Weight Load Development

[Matt P]

I hope this isnt a repost.

I spent an hour re-finding this site. This is excellent information in my humble opinion on load development.

I can not vouch for the accuracy of the article, but it may be an excellent place to start, or help you in a potential direction.

It will be a shame for this thread to get buried. Maybe stickied?

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 win 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...

For all the article go here below.

http://home.earthlink.net/~dannewberry/dannewberrysoptimalchargeweightloaddevelopment/

[ocabj]

I saw this a few years ago. The theory is sound. It basically says that you should find a load that won't fall apart if there is a slight inaccuracy of the charge weight.

I see guys who test rifle loads in .1gr increment. I think that's overkill. If you have a load that shoots great at say 25.0gr, but falls apart at 24.9gr or 25.1gr, I wouldn't even use it (assuming the inaccuracy is solely attributed to the load and not the operator). That's because .1gr is just too fine a value and odds are, most of us are throwing/measuring charges for each round with a variation of +/- .1gr or even +/- .2gr.

One of the High Power shooters I've met mentioned how he throws his charges with a simple RCBS powder measure without handweighing each one. He'll check a throw every now and then to make sure it's not severly off, but for the most part, he throws directly into the case. Plus, this guy is a High Master and he posts great scores.

[1911su16b870]

I have seen some Varget powder loadings that are consistent within +/- 0.5-grains. From the handbooks that is a +/- 50 fps variation in muzzle velocity. IMO if that is generally true, that is a forgiving powder to be using. Any additional feedback is welcome!

[Fjold]

The top benchrest shooters throw all their loads. Granted they are using Harell's and other top level measures but they still throw all their loads. If I'm using a flake or ball powder I'll throw all my charges, the only loads I weigh anymore are with stick powders.

The key to throwing accurate charges is consistency. Getting a feel for your measure and doing it the same everytime. Many people throw charges "by ear" making the click of the powder measure at the top and bottom of the stroke the same everytime.