XRe Posted June 2, 2009 Share Posted June 2, 2009 The most consistent chrono (far better than putting plates out at distance, and doing the measuring (which is error prone), having to do math, etc) is an old, old school chrono that uses disposable paper sheets impregnated with metal wire. When the wire is cut, the skyscreen is tripped. Space at 2 feet, just like the current sky screens, using a bracket similar to current technology. Then you get an interference free, accurate measurement with much, much less room for error than current optical systems, and much simpler to set up and run than any sort of audible-plus-stop-plate system. The only difficulty is cost of the papers... (which is why they stopped using that version, plus the time element required to swap papers...) Being one of the two guys (shred being the other) that wrote the proposal sent to George Jones that became the current Appendix C, I can tell you that this stuff is not as easy as it sounds. The rules have to be reasonable enough for running a chrono that it can actually be done in less than ideal conditions (rare to have a match with ideal conditions). The intention was to protect the shooter from poor chrono operation as much as possible, while not making it so difficult to run the chrono that matches will choose not to run one... Our suggestions were a little more restrictive than what was passed, but overall, the current rules are much better than they were. Random ammo collection - if it could be done and result in all shooters having ammo pulled - would be the way to go, as much as possible. There have been large discussions in the past about this subject - you might go search on them and read up. There are obvious pros and cons to most methods - if "random" becomes "RO at stage 5 collects ammo from every shooter's magazine", then its not so random anymore... Link to comment Share on other sites More sharing options...
zhunter Posted June 2, 2009 Share Posted June 2, 2009 Interesting idea Certainly doable Remember, altitude would play a part Link to comment Share on other sites More sharing options...
CSEMARTIN Posted June 2, 2009 Share Posted June 2, 2009 I think Matt is on to something. Link to comment Share on other sites More sharing options...
Catfish Posted June 2, 2009 Share Posted June 2, 2009 I admit it. I HATE the chrono "stages". It's more black magic than anything else to me. I have yet to see a lot of ammo chrono the same pf over different chronographs, even if those chronos were side by side. Hell, even the chronos at one of the A4 matches a few years back got 20-25 fps difference between the two of them; and those chronos' screens were right next to each other! I hear ya when you say don't run at the edge - my loads are usually in the 172-175pf - but if that's the case, what's the point of having a 165 pf at all?! We all have stories - either through personal experience or from watching friends suffer through it - of going minor at a major match when the ammo was well above power factor at home. How's this for a solution? Design a knock down plate that can be set for minor and major power factor. I'm sure someone can be smart enough to design a system that requires "X" number of foot pounds to be knocked over. The system should have a base that can be used on rocks, grass, mud, gravel, whatever, and still be reliable. Have one plate for minor and one plate for major and there you go. Knock the plate down and you're good to go. Don't knock the plate down and you're scored as minor or "no score". If you wanted to be devious about it and make sure that shooters weren't using their super special chrono ammo, incorporate the plate(s) into stages at random.... then, not only will you be scored minor (at least!) but you'll get the mike as well.... Link to comment Share on other sites More sharing options...
el pres Posted June 2, 2009 Share Posted June 2, 2009 (edited) How's this for a solution? Design a knock down plate that can be set for minor and major power factor. I'm sure someone can be smart enough to design a system that requires "X" number of foot pounds to be knocked over. The system should have a base that can be used on rocks, grass, mud, gravel, whatever, and still be reliable. Have one plate for minor and one plate for major and there you go. Knock the plate down and you're good to go. Don't knock the plate down and you're scored as minor or "no score". Thats a great idea !! No fall down though, too much to go wrong, just a presure sensitive plate with a strobe activated by a Major Factor hit !! If you want you can keep trying to hit it .. If we could get somthing like this to be consistant it would eliminate all the problems of weighing bullets, etc.. Edited June 2, 2009 by P.Pres Link to comment Share on other sites More sharing options...
Skizeks Posted June 2, 2009 Share Posted June 2, 2009 All these solutions to the problem have there own problem! How do you check your load at home before you go to a match? Now you go out and set up your chrono and shoot a few loads over it. Then you can figure out your PF. But when you go to a match and you don't make Major. Well it was good at home. But to bad you are not at home now. You have to go with whatever the match chrono tells you! The two plate idea sounds good. But how do you duplicate it on hundreds if not thousands of ranges across the country? The Human factor will come back and bite you on the backside. OK it's out there! Duane Link to comment Share on other sites More sharing options...
Skizeks Posted June 2, 2009 Share Posted June 2, 2009 How's this for a solution? Design a knock down plate that can be set for minor and major power factor. I'm sure someone can be smart enough to design a system that requires "X" number of foot pounds to be knocked over. The system should have a base that can be used on rocks, grass, mud, gravel, whatever, and still be reliable. Have one plate for minor and one plate for major and there you go. Knock the plate down and you're good to go. Don't knock the plate down and you're scored as minor or "no score". Thats a great idea !! No fall down though, too much to go wrong, just a presure sensitive plate with a strobe activated by a Major Factor hit !! If you want you can keep trying to hit it .. If we could get somthing like this to be consistant it would eliminate all the problems of weighing bullets, etc.. Just the speed of the bullet doesn't tell you a PF!! and ain't that what we are looking for? Maybe I'm missing something! Duane Link to comment Share on other sites More sharing options...
BritinUSA Posted June 2, 2009 Share Posted June 2, 2009 Back in the dim, distant pass I think they used a pendulum to calibrate the ammo. A plate with a weight at one end, and it if moved by a certain amount then you were good to go. As someone said it shouldn't be hard to figure out the minimums to move it. Assume the lightest bullet for each division and make it work. It would probably be more reliable than the chrono's have been. I've seen a wide variety of PFs from the same chrono, but it may be down to altitude. Link to comment Share on other sites More sharing options...
el pres Posted June 2, 2009 Share Posted June 2, 2009 ft/lbs. of energy.. Link to comment Share on other sites More sharing options...
larry cazes Posted June 2, 2009 Share Posted June 2, 2009 (edited) Random ammo collection - if it could be done and result in all shooters having ammo pulled - would be the way to go, as much as possible. There have been large discussions in the past about this subject - you might go search on them and read up. There are obvious pros and cons to most methods - if "random" becomes "RO at stage 5 collects ammo from every shooter's magazine", then its not so random anymore... Dave, I suspect that to do a truly random pull for hundreds of competitors would require a large amount of manpower over what is done today. I do agree, though, that anything less than truly random would be a waste of increased effort. I would be curious to see how you would go about a random pull at a nationals level match. Edited June 2, 2009 by larry cazes Link to comment Share on other sites More sharing options...
bbbean Posted June 2, 2009 Share Posted June 2, 2009 Even without the timer. If you had 2 stop plates each a different distance from the shooter, have a couple rounds fired at each. Knowing the difference in the distance of the 2 stop plates, and the time difference, you could calculate the average speed of the bullets. That would bring atmospheric conditions and bullet ballistic coefficient into the equation big time... probably more complicated to get it "right" than the current process. No more so than they are under the current system. We're not measuring theoretical velocity, we're measuring actual velocity. I think this idea has a lot of merit. Link to comment Share on other sites More sharing options...
Singlestack Posted June 2, 2009 Share Posted June 2, 2009 I have been playing this game for 10 years and I have never seen or heard someone try to cheat a chrono. Every time I have seen someone go minor they were shocked. Chrono's are VOODOO. Link to comment Share on other sites More sharing options...
BlackBuzzard Posted June 2, 2009 Share Posted June 2, 2009 (edited) We all know chronographs are not repeatable to within an acceptable margin of error that we expect in our sport. And to add a new testing apparatus makes it more complex, and its something we dont want to buy. My solution? Keep it simple and less painfull. If you get between 163 and 165 PF, its an automatic single procedural - thats all and thats within what I've seen as the margin of repeatability of chronographs. Below 163 and you are scored minor. We cant just keep on pretending that the chronographs we use are even remotely accurate to the significant digits we record. The real tragedy here is all the time wasted on this stupid "stage".......when we could otherwise have an extra REAL shooting stage at major matches. BB Edited June 2, 2009 by BlackBuzzard Link to comment Share on other sites More sharing options...
dqshooter Posted June 2, 2009 Share Posted June 2, 2009 The biggest change I would like to see is for the MD to make the chrono RANDOM, collect ammo from the belt or dropped mags at RANDOM and send the shooter to the chrono then. It is too easy for what I believe to be just a few people to pull 'special' chrono ammo when asked for the chrono sample. I think one of the biggest reason people see changes in their own power factor is not chrono'ing a new lot number of powder or bullets, not paying attention to how many times the brass has been fired and loading accordingly, etc. Random Chrono is the only way to go. I find it very interesting that GMs can shoot that fast and accurate when they are on the run, but somehow have a hard time shooting through the chrono. Seems like if you shoot the chrono arms you should be done for the match. I have been on squads and overheard " did you bring Chrono ammo" during several matches. Link to comment Share on other sites More sharing options...
XD Niner Posted June 2, 2009 Share Posted June 2, 2009 (edited) The major technical challenges with the stop plate appraoch would be to maintian a constant distance with very tight tollerances, keep the plates perfectly flat, account for the fact that the noise level required is not instantaneous but builds over a very short yet measurable amount of time and to be able to account for the distance effects for registering the sound. Light travels much faster than sound so it is inherently a more accurate measuring device over very short time periods. Edited June 2, 2009 by XD Niner Link to comment Share on other sites More sharing options...
Matt Cheely Posted June 2, 2009 Share Posted June 2, 2009 The major technical challenges with the stop plate appraoch would be to maintian a constant distance with very tight tollerances, keep the plates perfectly flat, account for the fact that the noise level required is not instantaneous but builds over a very short yet measurable amount of time and to be able to account for the distance effects for registering the sound. Light travels much faster than sound so it is inherently a more accurate measuring device over very short time periods. The stop plate approach isn't using sound at all. It's going to be an electronic impulse when the plate registers a hit. Yes, they would have to be a known distance apart, but you could build a rig that held the plates pretty easily. The problem would be that you're introducing bullet splatter right where your rig is at and that would necessitate it being built up pretty good, and therefore not very light and easy to transport. Link to comment Share on other sites More sharing options...
mactiger Posted June 2, 2009 Share Posted June 2, 2009 We all know chronographs are not repeatable to within an acceptable margin of error that we expect in our sport.And to add a new testing apparatus makes it more complex, and its something we dont want to buy. My solution? Keep it simple and less painfull. If you get between 163 and 165 PF, its an automatic single procedural - thats all and thats within what I've seen as the margin of repeatability of chronographs. Below 163 and you are scored minor. We cant just keep on pretending that the chronographs we use are even remotely accurate to the significant digits we record. The real tragedy here is all the time wasted on this stupid "stage".......when we could otherwise have an extra REAL shooting stage at major matches. BB I disagree, and I have fairly extensive experience with Nationals chronography to back that up. I don't run it, but I know the guy who has for the last 10 years or so, and I'd bet that he'd disagree, too. I've seen some of his historical data; with the proper setup, the chronograph is accurate and reproducible. The problems arise when proper care in setup and operation aren't taken. I know this, too, because I've thrown out several chronograph stages because of it. My opinion is that chronograph is the way to go, simply because a lot of people can get their hands on them. No special setup, no mechanical issues. But, that's just me. Troy Link to comment Share on other sites More sharing options...
persona non grata Posted June 2, 2009 Share Posted June 2, 2009 IMO, random sampling of ammo for the chrono = when you drop a magazine on a stage, after "range is clear!" the scorekeeper picks up the mag, strips 5 to 10 rounds out of it and puts them in a zip lock bag with a label. Link to comment Share on other sites More sharing options...
boo radley Posted June 2, 2009 Share Posted June 2, 2009 The major technical challenges with the stop plate appraoch would be to maintian a constant distance with very tight tollerances, keep the plates perfectly flat, account for the fact that the noise level required is not instantaneous but builds over a very short yet measurable amount of time and to be able to account for the distance effects for registering the sound. Light travels much faster than sound so it is inherently a more accurate measuring device over very short time periods. The stop plate approach isn't using sound at all. It's going to be an electronic impulse when the plate registers a hit. Yes, they would have to be a known distance apart, but you could build a rig that held the plates pretty easily. The problem would be that you're introducing bullet splatter right where your rig is at and that would necessitate it being built up pretty good, and therefore not very light and easy to transport. I don't understand -- don't you record the 'start' time using a timer? I haven't done the math, but you'd need the shot timer to be incredibly precise, along with whatever sensor you're planning on recording this 'electronic impulse' with. Not to mention the distance between 2 plates. Link to comment Share on other sites More sharing options...
Joe4d Posted June 2, 2009 Share Posted June 2, 2009 I know this is buried in alot of posts but the original post made several references to oiling the barrel before the chrono as cheating. Where in the rules does it say you cant oil your barrel before the chrono station ? Maybe I missed it. All I see is C- 32. Gun must be like it is being used or will be used. My gun barrel has oil in it now, and the match I shoot Sunday there will be oil in the barrel when it is used. So in a round robin chrono stage if my squad shoots the chrono as stage 5 why cant my gun be in the same condition as all the people who shot the chrono as stage 1 ? Link to comment Share on other sites More sharing options...
DarthMuffin Posted June 2, 2009 Share Posted June 2, 2009 I know this is buried in alot of posts but the original post made several references to oiling the barrel before the chrono as cheating. Where in the rules does it say you cant oil your barrel before the chrono station ? Maybe I missed it. All I see is C- 32. Gun must be like it is being used or will be used. My gun barrel has oil in it now, and the match I shoot Sunday there will be oil in the barrel when it is used. So in a round robin chrono stage if my squad shoots the chrono as stage 5 why cant my gun be in the same condition as all the people who shot the chrono as stage 1 ? If I were the chrono guy and I got a gun dripping with oil, I'd first fire a few shots into the berm and *then* take the chrono reading At that point, as the chrono guy, it's mine to do with as I will and there's no rule saying I can't "un-oil" it either. +1 on all the suggestions for truly random sampling. There are lots of ways to do this (not that I've ever ran a major match -- back seat match directing here). I'd probably pick a random time to sample each squad, such as barge in when they're in the middle of a stage and ask everyone in the squad to give you 10 rds from their front-most magazine and warn them that if the rounds come from anywhere else they'll be DQ'd under 10.4. Link to comment Share on other sites More sharing options...
XRe Posted June 2, 2009 Share Posted June 2, 2009 Dave, I suspect that to do a truly random pull for hundreds of competitors would require a large amount of manpower over what is done today. I do agree, though, that anything less than truly random would be a waste of increased effort. I would be curious to see how you would go about a random pull at a nationals level match. No argument there, Larry. It would be a bitch. You'll note what I said was (emphasis added here by me): Random ammo collection - if it could be done and result in all shooters having ammo pulled - would be the way to go, as much as possible. I was trying to convey that doing truly random ammo collection at a major match would be difficult, at best. The best way I can think of, though, would be to have several representatives of the match staff appear on different stages at the same time, and sequester the squad (perhaps minus the on deck shooter) and require the shooters to immediately fork over ammo from their belts or from loaded magazines in their bag (if they don't have any on their belt), or whatever - the idea being to try to pul ammo from the competitor that they appear to be intended to use in the match. The shooters should not be allowed to return to their bags without supervision (the only real way to be sure they aren't grabbing the "secret stash" ammo). The guy shooting can have his collected from his belt when he gets done shooting the stage. Its imperfect - and it has a greater "inconvenience" factor on the shooter - and if handled indelicately could cause some grief between the competitors and the match staff (you'd want to announce this procedure at the shooters meeting, I'd think, so no one was really surprised by it...). Its about the only sort of way I can come up with that avoids just surprising one shooter on the squad, and then everyone else catching a clue and quickly loading their mags with the "good stuff" - or that involves some logistical nightmare of trying to figure out who you've collected before they get to the chrono, etc... Anyway, true random collection is almost certainly not practical when running a real match - but something more random than "everyone give me 8 bullets" is probably better... Link to comment Share on other sites More sharing options...
Joe4d Posted June 2, 2009 Share Posted June 2, 2009 I know this is buried in alot of posts but the original post made several references to oiling the barrel before the chrono as cheating. Where in the rules does it say you cant oil your barrel before the chrono station ? Maybe I missed it. All I see is C- 32. Gun must be like it is being used or will be used. My gun barrel has oil in it now, and the match I shoot Sunday there will be oil in the barrel when it is used. So in a round robin chrono stage if my squad shoots the chrono as stage 5 why cant my gun be in the same condition as all the people who shot the chrono as stage 1 ? If I were the chrono guy and I got a gun dripping with oil, I'd first fire a few shots into the berm and *then* take the chrono reading At that point, as the chrono guy, it's mine to do with as I will and there's no rule saying I can't "un-oil" it either. +1 on all the suggestions for truly random sampling. There are lots of ways to do this (not that I've ever ran a major match . Not sure where you got that from either, there is no provision for a chrono guy to "do what he wants" What the rule does say is the Chrono guy can have the Competitor fire up to six rounds in the berm. I was actually interested in actual rules or official interpretations that say I cant swab my barrel before a chrono stage, I swabbed it before the match started and I have often swabbed it a time or two during a long match in sandy conditions, so isnt a swabbed and oiled barrel in the condition it was used or will be used ? I do agree that if the ammo isnt randomly surprise collected then it isnt much of a test. Link to comment Share on other sites More sharing options...
Matt Cheely Posted June 2, 2009 Share Posted June 2, 2009 The major technical challenges with the stop plate appraoch would be to maintian a constant distance with very tight tollerances, keep the plates perfectly flat, account for the fact that the noise level required is not instantaneous but builds over a very short yet measurable amount of time and to be able to account for the distance effects for registering the sound. Light travels much faster than sound so it is inherently a more accurate measuring device over very short time periods. The stop plate approach isn't using sound at all. It's going to be an electronic impulse when the plate registers a hit. Yes, they would have to be a known distance apart, but you could build a rig that held the plates pretty easily. The problem would be that you're introducing bullet splatter right where your rig is at and that would necessitate it being built up pretty good, and therefore not very light and easy to transport. I don't understand -- don't you record the 'start' time using a timer? I haven't done the math, but you'd need the shot timer to be incredibly precise, along with whatever sensor you're planning on recording this 'electronic impulse' with. Not to mention the distance between 2 plates. As long as the timer is picking up the sound of the shot from the same distance away from the gun for each of the shots, you can negate any difference the timer would cause. Shoot the 2 plates with say 5 rounds each. Now subtract the avg. of the times for each plate, and using the distance between the plates you know your velocity. You'd have to test it to see if it would actually work, but it would remove the light on the sensors as a possibility of error. For the record though, I still think that the chronograph is the best method overall. Link to comment Share on other sites More sharing options...
BlackBuzzard Posted June 2, 2009 Share Posted June 2, 2009 The chronograph is an instrument, not unlike say lab instruments. And as such, there should be accuracy and precision percentages listed in product manuals, but can find nothing out there. While my chrony displays 1382 fps, it might be incorrect to record it as such if (for example) the accuracy is +/- 1.5% or a range of 40fps. Any scientific reports out there that shed any light on what kind of accuracies we should expect? I bet the dudes at Aberdeen PG (at least in the old days) have some answers. And given that CED and others dont's make any statement at all, I sometimes wonder. BB Link to comment Share on other sites More sharing options...
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