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AggieMM wrote:Thanks for your input. I posted the summary above, here is the "raw data sheet".

Chrono Log - 8/9/2007

Group 3 is the one I like. Group 4 got too close to the floor for IDPA of 850 fps (using 147g bullet).

Tom, after you review the data above, I'd love to hear your thoughts......

Ryan

Ryan,

Well, my first obsevation would be to borrow whatever your brother has and use it.

Secondly, I have found that I get better (i.e. more realistic) readings when I use 10 shots rather than
5 for my groups. I have had some serious divergences in readings between the 5th and 10th
shot in a string. And in doing some recent reading on SD the consensus is to always use at least 10
data points of whatever you are testing. I started out using 5 too but always now use 10.
While it has opened up the SD and ES I feel that it has also given me more realistic results.
It also helps to explain (an alibi for) that occasional flyer.

Do you know the number of shots required for IDPA or IPSC to confirm that your loads are meeting
the minimum power factor? I don't which is the reason I am asking.

I would suggest that if all shots have to be over the minimum, and you are one or two SD's away
from minimum (from your lowest reading) with a 10 shot group, that you are in good shape.

If you are up to more shooting take your best two groups and shoot some 10 shot groups with those loads.
This will either confirm that you have great loads, which at this point seems to be the case,
or that you need to try a few more.

One other thing regarding the powder charge. I have not found that keeping the charge within one tenth
of a grain has been a useful exercise. It is very difficult to do and is not all that necessary for the type
of shooting that you are building loads for. Use your targeted load weight as a center point and just try to
stay only one tenth away from that center. It won't have a lot of effect on your results and may save
a bit of time and frustration.

Anyhow, loosen up a bit on your requirements, do more testing and don't get discouraged when your
results go nonlinear. Remember that at the core of all this there is a science. Finding it (the journey)
is the fun part.

BTW - I still keep all of my data in a spiral notebook, with pencil entries.
Your method appears to be superior in all respects. Good Job.

Kind Regards,

Tom

AggieMM wrote:As noted in my other post, First 100 Rounds Forum Post, my first loads were still too powerful for IDPA/IPSC. So I made up a few more. Here are the results for those:

Chrono Summary Log

I think I like the results from the 3.0 g load, 894 average looks good. The 2.9 g load is too close to the floor for my comfort.

Ryan

Ryan,

You might want to consider recording your HI/LOW, Extreme Spread, and especially, your Standard Deviation.
Also, I would be a little concerned not knowing for any given AVerage what the LOW reading was.

I don't use AVerage for much of anything useful, but rather try to get the SD and ES as low as possible.
These two are much better measures of consistency, both objectively and in relation to other loads.

Since you will be using these loads in matches you need to know how the particular match will test your loads.
Do they require that ALL rounds exceed a certain base number or just that the AV of a group of them does?
It would be a shame to have a nice average and have it fail the test due to a low reading or two.

You are keeping a nice set of load data but I would expand it as noted above.

As you evolve your hand loading into other calibers, especially rifle calibers, having more data to
assist in attaining the best consistency will save you lots of time down the road.
And consistency "generally" imparts accuracy. Except when it doesn't and we won't discuss that here.

Great start, and with a few tweaks you will have a better picture of your loads.

Kind Regards,

Tom