In a recent meeting to discuss some of our needs in preparing for WFTC 2021 Yankton, a couple of items were mentioned. We need to source 3 or 4 target testers and a cheap biodegradable filler for bum bags and kneeling rolls. Some ideas were tossed around but I thought I’d ask here for some additional input. Thanks. Uj
John;
The problem with the WFTF sanctioned tester is that very few match directors take the time to learn how to use it. And without careful use, it throws a bunch of FALSE POSITIVES, meaning that the target is deemed "good" when it is NOT.
The WFTF tester came about because of the stigma that pistols have in Europe, and as such, when carefully set and used it is an effective tool.
But for us, perhaps the best idea is to think of three or four Air Venturi V-10's.
SSP pistols that do not need much training to use. Safety googles are mandatory when testing, but it is clear proof that a target works or it doesn't. Most do not develop more than 2 ft-lbs, and so three test shots (top, middle and bottom of paddle) would definitely show if a target malfunctions or not.
And they are not expensive.
The three pumps of a Crosman 1077 commonly used are good, but they do take time and are a chore, and they also need careful use (half pumps done in a hurry can throw a lot of false readings).
As for the bio-degradable fill, I would suggest either the traditional Buck-wheat hulls, or the new Poly-Lactic Acid plastics (PLA)
Both can be had for about $1/kg and most shooters will be fine with 2.5-3 kgs
HTH
HM
John;
The problem with the WFTF sanctioned tester is that very few match directors take the time to learn how to use it. And without careful use, it throws a bunch of FALSE POSITIVES, meaning that the target is deemed "good" when it is NOT.
...
Thanks, Scott!
I had also forgotten the calibration part.
One of the problems of the target checker is that the threads are 3d printed, specially the ones of the limiting stop/depth gauge. And so in many Target Checkers I have seen, the depth gauge is not truly operational.
As with anything, most of the errors in the process will be human errors.
Thanks again!
HM
Hector thanks for the response. Using a pellet pistol as a target checker is something that none of us had thought of. In using one of these to check targets: 1. How far should it be held from the paddle when fired? 2. What FPE at the target is used to determine pass/fail? I tried to find a source for the Crosman 1077 but it looks like the model 1377 is their current pump offering. I like this idea vs trying to 3D print and build a checker provided the 1377 with X number of pumps is consistent, used properly and acceptable to WFTF. Thanks again! Uj
Hi all,
AARR has two of the target testers, that will be calibrated for the AAFTA National Championships.. and hopefully for the Worlds as well. I'm pretty sure Scott has one or two as well. AARR will come to the World event at Yankton a few days early to help, as we have committed long ago.
I'm wondering if the world rules will allow a pistol for challenges. The way I would read the rules, the target tester is the only allowed method... we should check.
We would for sure have to have well tested equipment and labor to use the equipment for testing of the targets. That has to be a top priority... imho.
Wayne
@John.-
Pistols can deliver as little as 2.5 ft-lbs. at the muzzle, so you should hold the pistol just off the KZ.
Pistols, like the V-10, are notable in that they deliver a CONSISTENT velocity, therefore power, of about 2.5 ft-lbs; with one single stroke. The target either falls or not, no further calibration of the testing device needs to be done. No caveats about usage, except for the safety and precautions of the use of a pellet pistol. Temperature will not affect it, and neither it is possible to use "wrongly" as far as testing is concerned.
I would hope that when things are being set up in Yankton, a special, closed, limited access, work range can be declared where targets are tested and set by two or three EXPERIENCED shooters.
One stroke makes for ease of testing. Let's say you need to test 150 targets, if you have to pump 3 times, that is 450 pumps. . . good luck.
So, I would NOT recommend the MSP, though it is possible. I've done it in GP's and it is a bear, but it can be done.
As rule 5.12 of the comprehensive rules says: Targets should be tested with high, medium and low impacts.
A pistol will allow you to put the impact where you want it. The WFTF target checker is nearly compromised when testing the low shot, unless you invert the tester and fire it with the index finger, not the thumb, and in this position, the stand-off / Depth Gauge is out of sight. Again, a question of training and certification of all the marshalls.
I would separate two different testing/calibrating requirements: a first approach with two stages that is PRIOR work, and then the Protest Procedure. Let's look at them:
On one first go around, you need to set up all the targets in a bench and calibrate or test that they ALL fall down with a low power impact delivered to the three positions in the paddle. That has NOTHING to do with WFTF. That is PRIOR work and it can be done in any way the hosts determine.
Then you need to set the targets in the course, level them, orient them, make sure they do not shake loose with a strong string pull, and THEN you need to RE-TEST all the targets IN PLACE.
That is also prior work that has nothing to do with WFTF.
Then in the last one or two days before the big match starts, ALL the marshalls, have to go around the course with properly calibrated WFTF target testers for two purposes:
a) To demonstrate that they KNOW how to use the tester under match conditions at ALL targets (whether set in a tree, in a ravine, or anything in between)
b) To ensure that all the testers are still calibrated (let's face it, guys they are PLASTIC tools! Whoever thinks they never go out of calibration needs to have their concepts checked).
If someone has problems, then there is still time to LEARN how to use the WFTF target checker properly, and/or resolve an accessibility issue to a certain target.
I have seen more points/targets thrown out of matches because the WFTF target checker failed/was not calibrated; was not 100% operable; the marshalls were not 100% trained, or other sundry cases than actual failures of the targets themselves.
The worst was to NOT throw away the targets, but delay the course of fire so much that only 2 days of shooting were done.
@ Wayne.- Thanks for everything you do for FT. MD's like you are the pillars of the sport.
IMHO We do need to distinguish between the PRIOR work and the PROTEST procedure (article 5.12) as outlined above.
Yes, under WFTF rules you need to resolve a dispute using the WFTF approved target checker, but that does NOT mean that all the prior work cannot be done with better tools and instruments.
IMHO, if we do all the PRIOR work properly and thoroughly, there will be FEW protests.
@ All
Please believe me I am not disparaging the use of the WFTF checker, I was in the development of it, know HOW, and WHY (it is an interesting story by itself) it was developed, and I know it WORKS.
I also know the shortcomings of the tool and the method, and for PRIOR/PREPARATORY work I think that we, in the USA, have access to better tools than the WFTF checker.
Keep well and shoot straight!
HM
Thanks Hector. My take away is that use of a 3fpe pellet pistol is OK for the “prior” testing, a SSP being better than a MSP. In the event of a protest, a WFTF approved checker is needed to resolve the protest. Question - how do you calibrate the target checker and how do you convey this proof of accuracy to the person who raised the protest? Uj
John;
The established/most common way of calibrating the tester is to use a properly falling target. You set the best target you have as a benchmark, then you make sure it is calibrated to fall with the established power level, and then you calibrate the Target checkers to make the target JUST fall. Again, plastic tools will vary from one day to the next.
As originally designed, you need to have a chrono with a small enough window that can read the end-point speed in the probe (either a Combro, or an Air Chrony) , then you can do a "momentum" calibration. Meaning that the momentum (Velocity times Speed) and not Kinetic Energy is what makes the paddles, and the targets, fall.
For this you need to weigh the mass of the probe and holder and then measure the velocity with the Chrony. Because the mass of the holder and probe depend mainly of the type of plastic that was used for printing it, it's necessary to weigh them.
There have been no instances that I have witnessed where someone challenged the checker, but it is not impossible.
A good way to defuse this situation would be to call all the RGB Reps a day before (which needs to be done anyway to let them handle the distribution of all the documents to the individual shooters), explain to them what was done, and demonstrate all the checkers that will be used.
In this way, the message is sent through the appropriate channels and in the appropriate languages.
If this was arranged well, you could even invite those RGB's that have their own target checkers to bring them and see for themselves. Of course a Suitable Air Chrony would have to be available (Combros are not commonly available here), to demonstrate the momentum calculation.
HTH
HM
