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164.97 Pf


Harmon

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i hate that my buddy went minor today.. 164.97 pf!

this can probably be contributed to cool weather(34 degrees!!!)

I know major is 165+ ...but i remember in physics in college that your answer cannot be more precise than your products...thus .75 X 2 would be 1.5 not 1.50 or 1.500.

bullet weight is held to four significant figures, so is velocity..but the power factor isnt..

If it was, he would be 165.0, not 164.97...

minor by .03 PF! hate it!

someone shot 152 pf ammo there...he would be better off...as he is still scored minor, but has less recoil..

harmon

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Sorry to hear what happened to your friend.

Last year, at the Florida sectional, A lady shooter was at the chrono before me and we were talking. The chrono man seemed to be shooting up all of her ammo, instead of the usual two or 3 shots. He finally turned to her and stated that she simply was not going to make it. She was horrified that she did not make minor until he stated that her ammo was 161 no matter what tricks he tried or how much he shot it was not going to make major. She replied 161! .... I'm supposed to be shooting MINOR and then starting beating her husband up for making her practically shoot major while scoring minor! Fun to watch but glad I was not resonsible for loading her ammo!

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Sorry to hear what happened to your friend.

Last year, at the Florida sectional, A lady shooter was at the chrono before me and we were talking. The chrono man seemed to be shooting up all of her ammo, instead of the usual two or 3 shots. He finally turned to her and stated that she simply was not going to make it. She was horrified that she did not make minor until he stated that her ammo was 161 no matter what tricks he tried or how much he shot it was not going to make major. She replied 161! .... I'm supposed to be shooting MINOR and then starting beating her husband up for making her practically shoot major while scoring minor! Fun to watch but glad I was not resonsible for loading her ammo!

Oh thank God! I'm not the only one who did something like that :D . I sent my wife to her safety course with my G34 and a bunch of old GI ball 9mm ammo I had sitting around. I went to the range a couple of days later to chrono some 45 ACP reloads and took the remaining GI ammo. After shooting it, I thought to myself, "HOLY SH*&", walked over and chrono'ed it at 1260. I felt soooooo bad. Thank god she didn't know the difference........ :o:D

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i hate that my buddy went minor today.. 164.97 pf!

this can probably be contributed to cool weather(34 degrees!!!)

I know major is 165+ ...but i remember in physics in college that your answer cannot be more precise than your products...thus .75 X 2 would be 1.5 not 1.50 or 1.500.

bullet weight is held to four significant figures, so is velocity..but the power factor isnt..

If it was, he would be 165.0, not 164.97...

minor by .03 PF! hate it!

Don't get me started on chronograph significant figures (a search will turn up the reams of arguments from the people that somehow think three thirds of a dollar equals 99 cents).... the truth is the real value was "165.0", since you only actually know one digit after the decimal point and have to round to get an accurate number. The rest of the digits are fiction brought about by calculators.

Did anybody else notice the recorded bullet weights at A4 were a little light light? My always-124.9 to 125.1 gr bullet was recorded at 124.6, likewise Alisons. Then due to some mixups, they reweighed the exact same bullet right there and it came in at 124.9. didn't matter for me, but for some others, who knows? :unsure::unsure:

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I remember that huge discussion a long time ago about power factor and number rounding/significant figures.

Conclusion was take the number before you apply significant figures and if it is less than 165.0, it is minor. Moral was don't cut it so close where errors in the scale and chrono becomes a factor.

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I remember that huge discussion a long time ago about power factor and number rounding/significant figures.

Conclusion was take the number before you apply significant figures and if it is less than 165.0, it is minor. Moral was don't cut it so close where errors in the scale and chrono becomes a factor.

Well, that's what the PTB's in international IPSC decided, because they just couldn't understand significant figures and some number of them get their jollies from seeing shooters with 164.999 PF's go minor. In reality, all that does was make the true minimum PF now about 165.25 or so..

that 'moral" will lead to a 3-lb trigger rule needing 3.5 lb triggers "just to be safe and not cut it so close". What's up with that? 3 should be 3 and 165 should really be 165.

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because they just couldn't understand significant figures

That's what I thought too. I've never been close enough PF-wise to have a personal stake at a match, but I can just imagine the blank look I would get if I uttered "significant digits" to the chrony RO.

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165.1 at my first big match, and the third round was 15 fps faster than the first two to save my butt. A couple days before that same ammo was making 181!!! That scared the hell out of me. Never again, changed to a less temp sensitive powder, reduced SD's to single digits, loaded to 173-175ish instead of 168-170ish and the last 10 times over the chrono I haven't gone under 170 no matter what.

Hope for the best and plan for the worst, or else......

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they came and told me the bad news...just before i chronoed(is that a word?)

i started to get all worried and stuff..

Roy, my bullet did come in lighter than i the ones ive weighted on scale which is inside, not affected by wind. they normally are 124.3ish but there they were 123.8...not a big deal to me, but that much difference could cause you to shoot minor if your close.

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To me the biggest issue I've seen lately is the ability to walk up to the chrono, hand them whatever ammo you wish, and declare a bullet weight. I'd prefer to not say what matches thats been, but if you go minor honsetly and others "creatively" make major that bugs me. Do it right or don't do it at all...

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Hey, those numbers sure look awfully familiar! :)

From my last chrono visit:

Sunday November 12th, 2006 54 degrees WINDY

Glock Factory Barrel Green G35 4.3G-Titegroup 180 MG JHP

932.5

931.7

925.3

941.5

936.1

939.8

963.6

942

945

939.72 169.15

Guess there is a big difference between 54 degrees and 29, huh? :P:P

I had fun, met some new friends, saw some old friends, and came away learning that Titegroup is a tad temperature sensitive. Who'd a thunk it'd be 29 degrees?

No one to blame but me....but boy, I'm going to have nightmares about those damn things for a while!

-Mike

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To me the biggest issue I've seen lately is the ability to walk up to the chrono, hand them whatever ammo you wish, and declare a bullet weight. I'd prefer to not say what matches thats been...

Well, let's see... last one I went to that did that was... the Open Nationals... :D Ken and Greg kinda looked at me funny when I told them I had a 230gr bullet weight though... :lol:

(it was a 125gr HAP...)

The fact of the matter is, unless there are very strict controls over how the data is gathered, chrono procedures are a farce. Plain and simple. And they tend to screw more shooters than they help... A match that cares so little about it that weighs bullets out in the open - no shielding from the wind - obviously doesn't understand that the chrono is worth more points than the rest of the match combined, at a typical large match.

I've been intending to write a nice letter to the BOD, Pres, and Front Sight about it for a while... maybe now's the time... For something to be so important to our scores to be handled so non-chalantly is, well... insulting to me... While this rulebook rewrite is going on, how about some additions to the chrono side of things (like, no weighing bullets in the open air without protection from air currents???).....

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To me the biggest issue I've seen lately is the ability to walk up to the chrono, hand them whatever ammo you wish, and declare a bullet weight. I'd prefer to not say what matches thats been...

I've been intending to write a nice letter to the BOD, Pres, and Front Sight about it for a while... maybe now's the time... For something to be so important to our scores to be handled so non-chalantly is, well... insulting to me... While this rulebook rewrite is going on, how about some additions to the chrono side of things (like, no weighing bullets in the open air without protection from air currents???).....

And verifying the scale periodically (like say, before and after each squad) with known check-weights and tossing the chrono if the scale can't be calibrated (just like if the official match calibration ammo varies too much during the match)

Current chrono proceedures are designed to catch the slightly careless or just plain unlucky shooter that means to do right, while letting the hardcore cheaters skate on by.

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Given all the variables beyond the shooter's control, such as temperature, wind (when weighing bullets outside - doh!), chrono variances, scale variances, etc., I don't understand why a reasonable margin of error can't be allowed (or is it, I've never been to a major match.) The technical specifications for the scales and chrono probably spell out the manufacturer's confidence level. Midway states for their scale, as an example, "Accurate to plus or minus 1/10th grain." Failing to take equipment variances (with the published variances being under IDEAL circumstances no less) and declaring that 164.97 is minor is a huge disservice to the shooter. The whole chrono thing should be to weed out those who are deliberately powder puffing their loads. This shooter obviously was not.

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..I don't understand why a reasonable margin of error can't be allowed ...

While I don't really agree with the variances, procedures and allowances...there is plenty of error margin built in. Nobody is required to shoot ammo within 5pf of the floor, yet so many do. :unsure:

(sorry if this is too much discussion in a hate rant. If the thread starter would like the discussion closed, let me/us know)

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While I don't really agree with the variances, procedures and allowances...there is plenty of error margin built in. Nobody is required to shoot ammo within 5pf of the floor, yet so many do. :unsure:

That's why my loads are 170ish PF. Should I ever have the time and money available to shoot a major match, I don't want my experience ruined at the chrono. Even so, I'd be crossing my fingers due to the subjective nature of the process. :(

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..I don't understand why a reasonable margin of error can't be allowed ...
While I don't really agree with the variances, procedures and allowances...there is plenty of error margin built in. Nobody is required to shoot ammo within 5pf of the floor, yet so many do. :unsure:

Flex,

I figured if I was making 171 that was enough tolerance and should be fine. I've got no one to blame but bad luck, myself, and COLD weather! :P I 'could' go hotter, but if I only need 165, would be kinda silly to shoot 180-- no biggie, either way. I'm going to rechrono my loads on another CED chrono just to see if the numbers off it are consistent with mine (which ISN'T a CED) or the one at A4.

As far as the margin of error-well, no one can ever say I had special chrono ammo. :lol:

No worries. Live and learn. I doubt I'd have beat Dave or BJ either way. ;) I had a great time, felt good about the match, and spent time with a lot of great people.

I get to do it again in 6 months, and I won't change my load. I'd bet ya dollars to donuts it'll make 170. (It'll be like 312 degrees in June in Louisiana!!)

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