Load Development-is there a logical way?

[InTheBlack]

They say every gun has a "most accurate" load.  But I've never seen an article describing a non-random method of discovering it.  Aside from swaging to optimize diameter, which most people don't have the equipment to do, where should you start?  There ought to be some hints in the physcial laws of ballistics!

Should you start by picking one bullet weight/style and one powder, varying charge? Or maybe first shoot several bullets in order to see if one performs better?  Etc. Etc.

I suppose you need to start be defining lower limits for what is important for the defined task.  Muzzle velocity- low for close range, high for long range.  Kinetic energy- low for target or high for hunting?  Long (thus heavy) bullet for long range stability?

The same velocity can be achieved with several powders having different burn rates.  This will change the recoil impulse and affect both felt recoil and barrel harmonics.  But I don't have a reference that tells me how much of a burn rate difference is needed to be significant.  Nor a quantitative list of burn rates.

Anyone have an opinion on what elements are the most significant?

[Patrick Sweeney]

What you are asking for is a B.S. in Ballistics in the short form.  When I figure out how to write it, I will.

The idea that a firearm has a "most accurate" load is statistical witchcraft.  What you want is to find a load that is accurate enough for your purposes.  First, define the limits.  What passes muster for IPSC will not neccesarily do for the Bianchi Cup.  (Accuracy-wise.)

Settle on a bullet weight for your purpose.  Pick a powder in the middle of the appropriate range, and start loading.

Check velocity and accuracy as you work up.  

The results will be a reflection of your attention to detail.  If you "test" accuracy by shooting over a sandbag at a paper plate, you won't have the same statistical confidence in the results as you would testing with a Ransom rest anchored to the earth's crust.

Yes, it is random.  That's why everyone in the Enosverse is willing to help out, as a group effort to combat the randomness of the universe.

[Steve Anderson]

I for one wish I could shoot well enough to worry about the accuracy potential of a load/gun combo. I've only seen BAD accuracy in one powder - Titegroup at lower than book velocities.

I load for feel and find accuracy to be MY problem!

[benos]

Patrick,

"That's why everyone in the Enosverse is willing to help out, as a group effort to combat the randomness of the universe."

LOL!

What Patrick said...

be

[jmaass]

Much is to be learned by taking advantage of the experiences of others. What proved accurate for one gun may be close to optimum for yours, but at worst could provide a good starting point.

Way too many variables for a cookbook approach to work.

There are many sources for that. For many years, Handloader Magazine has published a Pet Loads column, and I got my reloading start poring over the many 9mmP loads there.

Reloading articles (notably by Layne Simpson) include sets of data in the author's particular gun(s), although he tended to favor heavy bullets (130+) in .38 Super long after most everyone else moved to lighter weights (125 and down).

The idea that putting all this information together would provide a roadmap and safety double-check was the reason that I started gathering the "IPSC Loads Lists" for my own use. I can tell for a new powder / bullet combination what has been tried, and that puts me within a few tenths of a grain of a safe load for my guns. Once you have  a safe load, you can test and tweak for accuracy.

The variation between guns can be amazing, though. An accurate Major load in your gun might be minor or  a stinker in a friend's.

That's part of what makes reloading an interesting endeavor!

[Joe]

The sum of all parts equals accuracy.  In theory anyway.

Another words everything you use i.e. cases, bullets, primers and powder should be as identical as possible.  Except in the case of primers this is determined by weighing each individual component.  Weigh each case after it has been trimmed to the lenght desired.  Sort into lots that give you the least deviations from the average.  Do the same with your bullets, except the trimming of course.  Weighing each powder charge individually load 10-20 each in .1 grain increments.  Seat and crimp these at the min overall length.  Fire these at your test distance and determine if any one meets your requirements almost.  The one that 'almost' does should be loaded for testing in 10-20 round lots in increments of +.002" OAL, example x.xx2, x.xx4...  Ensure that you never seat the bullet so long that it contacts the rifling.  Then test fire these again.  You should be 'there'.

The 'short course' for IPSC/USPSA/IDPA would be to use a 'known' load that makes your pf and is somewhat accurate and tweek it.  Use the same headstamp cases and, even better, from the same lot.  Trim them to equal length.  Check your powder charge weight frequently.  Seat 10-20 each at the minumum length that will function.  Do the same in increments to the longest OAL that will function.  Hopefully one of these will be 'there'.  Check that one over the chrono to insure it still meets pf.  

HTH,

Joe

[Joe]

Guess I should of said what I 'actually' do.

Load cases of the same headstamp in .2gr increments at whatever oal I choose.  Fire these and whichever is 'best', load more test rounds at .1 above and .1 below.  Pick the best of the three and experiment w/OAL.

For competition load development it is chrono for pf using the same headstamp then changing OAL in increments.  I then chrono that load using the other cases I have.

Just what 'accuracy' goals do we have for IPSC/USPSA/IDPA?  3 to 5 inches at 50 yards will put you on an 8 inch plate if you do your part.  Is that 'good' enough?

Joe

[BSeevers]

Now I just dip the case, any old case, in bullseye, very carefully take a knife and with great percision knock off all extra powder, seat any bullet with a short OAL. Just kidding although I have been at ranges where an idiot was doing that. He was using a screwdriver to pound cases out of a 44 Mag. I gotta go is all I said.

The vv loading manual have a burn rate of all powders listed in it. I am sure you can get it on web or other books. I have tried many other bullets, brass and components. Some are crap but the majority are very good. Use proven stuff and you will be fine. In pistol competition ammo obsessiveness is not a great concern, except for Masters long range type shooting. Check out rifle benchrest shooting info if you are really into this. I did take a little from them. I am NOT weighing/separating my components.

[1badmagnum]

how about when you have load data and componants known to produce accurate rounds and you want to try another powder where no data is available?

I want to develope some loads for my 50 ae desert eagle using titegroup and hs-6.

[Flexmoney]

I'd give a call to the powder and bullet companies.  They are often ready to help.

[George D]

Anyone noticed a correlation between low standard deviations for velocity and high accuracy?