Popper Calibration & Challenge

[mactiger]

This is one time where my OCD kicks in. If a person is going to claim to be a Match Director, then there are rules that must be followed. If they are not following the calibration rule, then what other rule is subject to comprise. Follow the rules or stay home.

So we need to set up a chronograph and do that whole process for a level one match as well. If none of the ammo is checked why check the calibration ammo? If I am going to design, help build, produce the score sheets, manage the match and generally keep everyone else happy in all ways, field phone calls from strangers and newbies at all hours about the club and the sport why is it incumbent on me to produce at my or the club expense a package of special calibration ammo as well? If I don't do that then I am just not pulling my weight? The whole inegrity of the sport and western civilization is in danger because my chrono ammo is winchester white box or whatever the shooter has? Really?

Or, you could delegate this to someone else. I'm sure you have some help there, because when I taught the class, there seemed to be a bunch of able bodied people. Someone could load up a few hundred rounds of calibration ammo for the club's use, I'm sure.

Troy

[mactiger]

Poppers that have been hit/driven down, esp those as activators, should be setup and shot with calibration ammo after the run. The competitor would chose whether he/she wants to accept the current run (like interference) or have a calibration shot taken. IF the popper fails during calibration then she/he must reshoot. Also, if there is a popper challenge on a hit, where the popper didn't fall, the calibration shot should be taken and If it falls then it should be reset and shot again because we don't know what state it was in after being hit 1-3-x times.

There's to much room for inequity with these targets... I think it's time we did something about it.

That's all I have to say about it....

JT

CRO's and RO's can "manage" the steel; i.e., keep it light and adjusted between competitors if it's noted that the steel is becoming a problem. The popper calibration rules work well as is. Once again, most problems like this can be avoided with proper setup and management of the steel--radical rule changes are not needed. Bad answer, Grasshopper!

Troy

[JThompson]

Poppers that have been hit/driven down, esp those as activators, should be setup and shot with calibration ammo after the run. The competitor would chose whether he/she wants to accept the current run (like interference) or have a calibration shot taken. IF the popper fails during calibration then she/he must reshoot. Also, if there is a popper challenge on a hit, where the popper didn't fall, the calibration shot should be taken and If it falls then it should be reset and shot again because we don't know what state it was in after being hit 1-3-x times.

There's to much room for inequity with these targets... I think it's time we did something about it.

That's all I have to say about it....

JT

CRO's and RO's can "manage" the steel; i.e., keep it light and adjusted between competitors if it's noted that the steel is becoming a problem. The popper calibration rules work well as is. Once again, most problems like this can be avoided with proper setup and management of the steel--radical rule changes are not needed. Bad answer, Grasshopper!

Troy

Didn't seem to work to well at a recent National...

JT

[mactiger]

Depends on which side of the calibration you were on.

[JThompson]

Depends on which side of the calibration you were on.

I had a guy laughing here before, but I removed him.

There is no calibration as this shooter drove the popper because they could not afford to risk a calibration where there would be possible FTEs involved. I think the rules regarding poppers are inadequate at best. This is one of those that I will not agree on no matter how much we discuss it.

I don't have to agree with a rule to be bound by it, but I will not agree with a rule I feel is inconsistent. If they screwed it up at a national, with all those high powered very experienced RM, CRO, ROs then what makes anyone think it works as is? At LII matches where we have less experienced ROs the problem is exacerbated. Nope, this is the biggest area of "gotcha" in the sport today imho.

JT

Edited April 2, 2011 by JThompson

[Jim Norman]

My problem, which I have expressed often, is that shooting a popper after it has been hit is not shooting the popper in the same condition that the that the competitor has shot it in.

I test Fire Doors as a part of my business. When you test a fire door (before a fire) you activate it, then you reset it and activate it again, then you reset it. This is done to verify that the person doing the check actually knows how to properly reset the door.

Popper set-up should be done in the same manner. Set it up, test it, reset it and test it again. This handles the initial calibration ONLY. If the steel is a) properly set, it is painted between shooters and c) the shooters are all making minor or better, then a properly set steel MUST fall when it receives a full diameter hit in the calibration zone or higher. Failure to fall with that hit should be grounds for a reshoot. If the shooter hits it low and uses multiple hits to drive it down, no reshoot.

Once the shooter has hit the steel in the proper area and it has NOT fallen, shooting it again as it stands is bogus. At this point a strong gust of wind could take it over, heck a fly fart may be all it takes.

It is up to the set up crew and the RM to make sure the steel is properly installed on the range so that calibrations for failure to fall don't happen. Soft ground? Put a 1/4 sheet of plywood under the steel, uneven ground? Shovel!

Ideally we need a device that will impart a specific impact to the steel every time. Sort of a ballistic hammer so that at the beginning of each squad, the steel can all be verified. We are better now than we used to be, at least calibration ammo has to be no more than minor (115 to 125PF)

Anyway, my rant is over.

[Pro-Pain]

I didn't know a squib left the barrel?

Squib is defined as: Squib - A bullet or solid obstruction lodged inside the barrel of a firearm.

Could have meant a squib that wasn't caught, but then shot out with the next round, or an under-powered/under-powdered load that doesn't make PF but still exits the gun.

In the early days of IPSC before chronographs were readily available (and cheap) they used a ballistic pendulum to measure power. I'm wondering why a pendulum couldn't be used to calibrate a popper. X weight swung Y distance from Z height (somebody better with math will have to calculate the X Y & Z) once those were known it wouldn't be very difficult for a club to build a simple frame and pendulum. Set it up in front of a popper and let fly (so to speak.)

F=MA. If you're solving for Force (power factor), 125 fps, and you know the weight of the object (the swinging pendulum) it's just a matter of seeing how far up to swing that weight from to generate that force. I'm sure there's a physics formula for determining speed out of an arc in perpetual motion, but that must be Physics II, I only took Physics I

For what its worth, I knew my gun / ammo combination was about 130 pf, so I shot a couple of inches below the calibration zone to try and compensate for the higher pf. I'm not saying that's the right thing to do, but without a calibrated gun/ammo combination it seemed like a good compromise. After reading the rules, I would be tempted to rule REF on any popper that doesn't fall, if the MD doesn't have a calibrated gun/ammo combo to challenge the popper calibration.

Wouldn't you want to hit ABOVE the calibration zone? The higher up on the popper, farther away from the resistance (the base) you would generate more force. Take a 2 liter bottle of soda, push on the cap, and then push on the base, and see which one you would have to push harder for it to tip over (obviously the top because you're generating more downward force when combined with gravity).

Does anyone (like AA or DC Ammo) make any 115-120 PF "calibration" ammo? My 9mm stuff runs about 130-135 PF. I suppose I could make up some special calibration ammo by downloading just a bit, but it hardly seems worth the bother if I can just buy some that I know will work since I hardly shoot 9mm anymore.

I haven't seen any. I wouldn't think, because these rounds would be sub-minor, and I don't think there would be enough demand to make just chrono ammo, when most people who would use it are level 2, 3, or 4 matches, and those MD/RM's, etc. either reload or know someone who reloads who could whip up a batch of chrono stuff. I could be wrong though, I just don't see it being feasible.

[JAFO]

For what its worth, I knew my gun / ammo combination was about 130 pf, so I shot a couple of inches below the calibration zone to try and compensate for the higher pf. I'm not saying that's the right thing to do, but without a calibrated gun/ammo combination it seemed like a good compromise. After reading the rules, I would be tempted to rule REF on any popper that doesn't fall, if the MD doesn't have a calibrated gun/ammo combo to challenge the popper calibration.

Wouldn't you want to hit ABOVE the calibration zone? The higher up on the popper, farther away from the resistance (the base) you would generate more force. Take a 2 liter bottle of soda, push on the cap, and then push on the base, and see which one you would have to push harder for it to tip over (obviously the top because you're generating more downward force when combined with gravity).

He knew his gun/load combo was making over the calibration ammo PF (130), so he fired low to try to counter the effect of his ammo being hotter than it should have been for calibration (115 -125).

[EkuJustice]

Usually around here, someone is sporting a 9mm carry gun thats a short barrel. Shoot it with some factoy wwb, blazer type ammo and be done with it. At a level 1 club match with nothing on the table is it really worth having to make the MD(who is shooting the match at the same time as you are not having shot it the day before on a staff day) run out grab the chrono ammo and gun and go over and shoot the popper to see it goes down. Its just going to end up taking extra time for everyone on the stage and back everything up. At a larger match sure but for the local weekly club match just make it easy for everyone and send an extra round down range into the target.

[Pro-Pain]

For what its worth, I knew my gun / ammo combination was about 130 pf, so I shot a couple of inches below the calibration zone to try and compensate for the higher pf. I'm not saying that's the right thing to do, but without a calibrated gun/ammo combination it seemed like a good compromise. After reading the rules, I would be tempted to rule REF on any popper that doesn't fall, if the MD doesn't have a calibrated gun/ammo combo to challenge the popper calibration.

Wouldn't you want to hit ABOVE the calibration zone? The higher up on the popper, farther away from the resistance (the base) you would generate more force. Take a 2 liter bottle of soda, push on the cap, and then push on the base, and see which one you would have to push harder for it to tip over (obviously the top because you're generating more downward force when combined with gravity).

He knew his gun/load combo was making over the calibration ammo PF (130), so he fired low to try to counter the effect of his ammo being hotter than it should have been for calibration (115 -125).

Ahh, makes sense, I get it now. I thought you guys knew a super secret ninja move about downing poppers

[Skydiver]

Usually around here, someone is sporting a 9mm carry gun thats a short barrel. Shoot it with some factoy wwb, blazer type ammo and be done with it. At a level 1 club match with nothing on the table is it really worth having to make the MD(who is shooting the match at the same time as you are not having shot it the day before on a staff day) run out grab the chrono ammo and gun and go over and shoot the popper to see it goes down. Its just going to end up taking extra time for everyone on the stage and back everything up.

Actually, it's the RM, not the MD who should do the calibration shot unless the RM has designated somebody else.

Anyway, but isn't finding "someone sporting a 9mm carry gun that's a short barrel..." also going to be about the same amount of extra time? If you are willing to take time to do this, why not take time to do it right?

Since this thread has somewhere floating in the background the question of whether to follow the rule to the letter or the spirit, let's say as I'm shooting I pull a shot a little early and end up hitting the ground approximately 10 ft away from me. I personally would be unhappy if the RO just eyeballed the 10 ft, or asked somebody to pace it out. I would like a measuring tape brought out to determine if it's truly an AD or not. For fairness, we'd all like to use the measuring tape. So in the same vein why wouldn't we want to use a gun and ammo combination that is a known quantity?

Edited April 2, 2011 by Skydiver

[Skydiver]

Let's say that a local club actually took time to make calibration ammo and had a designated calibration gun, but at the time that lot of ammunition made and tested right at 125 PF in the depths of winter. If you knew that the powder used was temperature sensitive, would you feel bad if you lost a calibration challenge in the middle of summer?

Personally, I would feel bad, but I can't challenge because of rule C1.3, and because C2.15 says "should".

Edited April 2, 2011 by Skydiver

[LPatterson]

Let's say that a local club actually took time to make calibration ammo and had a designated calibration gun, but at the time that lot of ammunition made and tested right at 125 PF in the depths of winter. If you knew that the powder used was temperature sensitive, would you feel bad if you lost a calibration challenge in the middle of summer?

Personally, I would feel bad, but I can't challenge because of rule C1.3, and because C2.15 says "should".

At least the club made an effort to abide by the rules. Even if you knew the powder was temperature sensitive (which most are), do you know which way and when the ammo was tested?

The vein of most of the threads is that at a Level 1 match the rules are getting in the way of having fun. If the club is willing to bend some rules how do you know they aren't bending others. Like pacing off distances on a classifier stage, afterall it is just a Level 1 match.

[Nik Habicht]

how do you know they aren't bending others. Like pacing off distances on a classifier stage, afterall it is just a Level 1 match.

I know by being involved in the running of matches at two of my local clubs.....

This isn't hard to know -- show up early, lend a hand, then you'll know....

[Singlestack]

how do you know they aren't bending others. Like pacing off distances on a classifier stage, afterall it is just a Level 1 match.

I know by being involved in the running of matches at two of my local clubs.....

This isn't hard to know -- show up early, lend a hand, then you'll know....

+1

That's a bit absurd.

[professor]

In the early days of IPSC before chronographs were readily available (and cheap) they used a ballistic pendulum to measure power. I'm wondering why a pendulum couldn't be used to calibrate a popper. X weight swung Y distance from Z height (somebody better with math will have to calculate the X Y & Z) once those were known it wouldn't be very difficult for a club to build a simple frame and pendulum. Set it up in front of a popper and let fly (so to speak.)

F=MA. If you're solving for Force (power factor), 125 fps, and you know the weight of the object (the swinging pendulum) it's just a matter of seeing how far up to swing that weight from to generate that force. I'm sure there's a physics formula for determining speed out of an arc in perpetual motion, but that must be Physics II, I only took Physics I

There's a couple of technical problems that come into play if we are going to redefine the calibration procedure in terms of an equivalent pendulum.

For starters, Power Factor [mass times velocity] is actually a measure of Momentum, not Force [mass times ACCELERATION]. The units of 'power factor' are grains-Ft/sec divided by 1,000. You could set up a pendulum with a known weight at the bottom of a light rod of known length, and raise that weight to a point such that when dropped the velocity at the bottom of the arc of travel times the weight's mass has the same momentum as the much lighter bullet travelling at the much faster muzzle velocity. Then comes the other problems.

Transfer of momentum between a bullet and the steel target that it hits is an extremely inelastic collision. Most of the time, the bullet shatters, or flattens, and piece fly off the face. All this is evidence that much of the momentum energy of the bullet is dissipated in ways OTHER THAN pushing the popper down. How much is dissipated is a function of bullet composition, bullet final disposition, angle of contact, 'softness' of the steel target, etc., etc. The pendulum weight would not break up [hopefully], and so more of its momentum would probably transfer into moving the popper. And THAT means that every popper would be calibrated HEAVIER than the bullets that are supposed to put them down.

IMHO, it would be a major research project to design a pendulum such that it provided equivalent 'oomph' to a target as the designated PF ammunition. You would then have to be able to set it up in the field to calibrate each and every piece of steel. And even then, you could not satisfy the current calibration specifications.

That is because steel is supposed to be calibrated from the furthest location on the stage at which a shooter could engage the target. If a piece of steel is set at the minimum distance allowable, it will experience a more powerful 'hit' than the same piece of steel at 30 to 50 yards. But our new pendulum standard could not duplicate the effect of distance without further research to determine how much lighter the 'hit' will be at those distances. A piece of steel engaged at an angle because of the shooters location will not have as powerful a 'hit' as a straight on square hit from the same distance. The pendulum standard wouldn't be able to duplicate that angle factor.

Properly calibrated PF ammunition will automatically make these adjustments by duplicating the distances involved, the angles of encounter, etc.

Finally, I believe this sport did use a pendulum device for ammunition calibration prior to the availability of chronographs. I suspect that pendulum use was discontinued because the mechanical assembly would experience more variability over the course of a match than the 'no moving parts' chronograph. I suspect that a pendulum device for steel calibration would suffer from similar problems. [This brings to mind the engineer slated for execution by guillotine, who is saved when the blade binds up in its tracks. Saved from immediate termination, the engineer looks up and comments, "I think I see what your problem is."]

Edited April 3, 2011 by professor

[eric4069]

Other forum members have mentioned that Rem UMC 115 9mm tends to come in sub-minor in some guns, why not just keep a box of that around for calibration? Better than nothing I guess.

Eric

[LPatterson]

how do you know they aren't bending others. Like pacing off distances on a classifier stage, afterall it is just a Level 1 match.

I know by being involved in the running of matches at two of my local clubs.....

This isn't hard to know -- show up early, lend a hand, then you'll know....

+1

That's a bit absurd.

What's absurd the question or the answer, afterall the astronauts went to the moon in an aircraft built by the lowest bidder. It would be nice if everyone showed up early to help setup stages but since most don't, our club sets up the day before. But even then if the leader of a setup crew decides to pace off a classifier, do you jump up and down and say that's not right or do you just let it go. To get back to the original post, since the rules include the word 'should' I think we 'should' work toward the spirt of the rule if not the 'letter' of the rule. If it is too much trouble to handload some calibration ammo, then how about at least chrongraphing some different brands through a gun that would be available to the RM/MD on match day. A favorite quote "If you are not part of the solution, then you are part of the problem."

[wileecoyote37]

I'm the Match Director for an upcoming championship match. I have been playing with the chronograph testing ammo. The chrono's are CED M2 set up with infrared lighting in a box - just like they use at Nationals.

One of the guys had some Federal 115 gr. FMJ RN factory ammo. He bought it to use in production at the next match and it DID NOT make minor.

Beretta 92 118.3 PF

Springfield XD 4" barrel 120.8 PF

Glock mod 17 aftermarket barrel 119.4 PF.

Taurus (copy of Beretta 92) 123.2 PF

This will make good calibration ammo and is easy to purchase (he bought his at Walmart).

I also found that 9mm 115 gr. moly coated RN with IMR 700x would consistantly chrono 115 to 118 PF out of a Springfield XD 4" barrel.

This should give MD's a good starting point when developing calibration ammo.

[West Texas Granny]

I guess it's just too simple to call a hit if indeed the round did hit the popper but it failed to fall.

[Flexmoney]

I guess it's just too simple to call a hit if indeed the round did hit the popper but it failed to fall.

Poppers are only calibrated for hits at/above the circle. A low hit or an edge hit may not take the popper down...and, while "hit" it is scored a Mike.

This is part of D.V.C. (power and accuracy)

Our rules clearly state that all steel must fall to score.

[wide45]

I'm the Match Director for an upcoming championship match. I have been playing with the chronograph testing ammo. The chrono's are CED M2 set up with infrared lighting in a box - just like they use at Nationals.

One of the guys had some Federal 115 gr. FMJ RN factory ammo. He bought it to use in production at the next match and it DID NOT make minor.

Beretta 92 118.3 PF

Springfield XD 4" barrel 120.8 PF

Glock mod 17 aftermarket barrel 119.4 PF.

Taurus (copy of Beretta 92) 123.2 PF

This will make good calibration ammo and is easy to purchase (he bought his at Walmart).

I also found that 9mm 115 gr. moly coated RN with IMR 700x would consistantly chrono 115 to 118 PF out of a Springfield XD 4" barrel.

This should give MD's a good starting point when developing calibration ammo.

Buy a bunch from the same lot now. You can't expect every lot to give the same power factor. Components can get switched out by the manufacturer.

[West Texas Granny]

I guess it's just too simple to call a hit if indeed the round did hit the popper but it failed to fall.

Poppers are only calibrated for hits at/above the circle. A low hit or an edge hit may not take the popper down...and, while "hit" it is scored a Mike.

This is part of D.V.C. (power and accuracy)

Our rules clearly state that all steel must fall to score.

But look at all of the time and resources that are required when a simple called hit would suffice. Not to mention the fact that the calibration Is never exact.

[bluenite]

But look at all of the time and resources that are required when a simple called hit would suffice. Not to mention the fact that the calibration Is never exact.

You can not leave something like that up to a call, it would have to be painted after each shooter, as is, it should only take 3 to 5 minutes before the match and should last the whole match.

If you hit low shooting minor it might not fall, requiring a second more precise shot.

If you hit low shooting major it most likely will fall.

One of the core principals of USPSA is power (power is rewarded).

I am happy with it as is.

[Olivers_AR]

Was at one match were the steel just wasn't falling, went ahead a doubletapped it just because it was faster then coming back for something that didn't fall.

Edited May 7, 2011 by Olivers_AR