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fnbrowning · December 9, 2002, 10:51 PM

There has been a couple of posts rambling on about some chronograph data. My, my, how some people can ramble on.

Okay, I will quite honestly admit that I copied straight from the spreadsheet without cleaning up the data. Now, there was one load - ONE - that accounted for the extreme spread. Could have been a defective primer. Happens to everybody. Okay, not some some people, you know who you are.

So here is my load with the ONE bad data point thrown out. Legal by the way to throw out a statistical aberration in experimental data.

Bullet/Weight Hornady 115 XTP
Powder/Weight Unique 6.1grains
Primer, Smith & Wesson
Cases Mixed, once fired

Velocity (fps) Deviation from Avg Velocity
1281 7.55
1256 17.44
1318 44.55
1285 11.55
1298 24.55
1250 23.44
1263 10.44
1262 11.44
1248 25.44

Total 11461
Number of Shots 9
Avg Velocity 1273.44
Avg Deviation 19.60

High Velocity 1318
Low Velocity 1248
Extreme Spread 70

Std Deviation 23.77

December 9, 2002, 10:51 PM	#21
fnbrowning Member Join Date: October 29, 2002 Location: Missouri Posts: 24	Whining about the data. There has been a couple of posts rambling on about some chronograph data. My, my, how some people can ramble on. Okay, I will quite honestly admit that I copied straight from the spreadsheet without cleaning up the data. Now, there was one load - ONE - that accounted for the extreme spread. Could have been a defective primer. Happens to everybody. Okay, not some some people, you know who you are. So here is my load with the ONE bad data point thrown out. Legal by the way to throw out a statistical aberration in experimental data. Bullet/Weight Hornady 115 XTP Powder/Weight Unique 6.1grains Primer, Smith & Wesson Cases Mixed, once fired Velocity (fps) Deviation from Avg Velocity 1281 7.55 1256 17.44 1318 44.55 1285 11.55 1298 24.55 1250 23.44 1263 10.44 1262 11.44 1248 25.44 Total 11461 Number of Shots 9 Avg Velocity 1273.44 Avg Deviation 19.60 High Velocity 1318 Low Velocity 1248 Extreme Spread 70 Std Deviation 23.77 __________________ "I'm your biggest fan, Ms Blake . . . . Well, the most heavily armed anyway"