1.125 multiplier is added in. that is 12.5% for targets 45 yards and further. It should be a steady progression but isn't.
Here is the system in Brads words:
"FT Course Difficulty Rating System
Years ago I developed a simple method for estimating the difficulty of the courses I was designing. It gave me an idea of how easy or hard the individual target and overall course would be for an upcoming match. There have been some questions about the system recently so I thought it would be a good time to write about it again.
When I first developed the rating system, I played with some factors and equations until I settled on using the distance (in yards) divided by the kill zone size to give a difficulty rating for each target. For example, a ½ kill zone Squirrel placed in a tree at 21 yards would have a difficulty rating of 42 while a 1 skunk at 32 would be rated at 32. Once the individual difficulty rating for each target is known the overall course rating can be determined be averaging all the individual target difficulty ratings.
After a few years of using the system and input from other users, the following difficulty rating charts were developed. The chart on the left relates the difficulty factor to a degree of hardness for individual targets while the chart on the right does the same of the overall course difficulty. Two charts were developed since there can be different factors involved when figuring the overall course difficulty. A single target with a DF of 37 is considered Hard, but if you string a whole bunch of them together on a course then there are fatigue and concentration factors that come into play during the match which puts the course on the Expert level.
T.D.F.= Troyer Difficulty Factor Difficulty Ratings
Rating TDF
Easy 0-19
Moderate 20-29
Hard 30-39
Expert 40+
As others used the system it was pointed out to me that some another factor needed to be added to the system for shots that were more difficult than others like standing, kneeling or extra windy shots. So a difficulty factor was added to the equation making the difficulty rating equation:
Difficulty Rating = (Distance / Kill Zone Size) * Difficulty Factor
With a bit of testing and tweaking of the difficulty factors, the following difficulty factors have been developed:
Type of Shot Difficulty Factor
Standing 1.75
Kneeling 1.5
Windy Shot 1.25
Extreme Up/Down 1.25
Extreme Dark/Light 1.25
Shots past 45 yards 1.125
This system has worked really well for accurate course planning and it allows for better comparisons between matches from different venues. The system can be teamed up with a spreadsheet program to facilitate match planning. A sample of the course planning spreadsheet I use (in Microsoft Excel) has been posted on the AAFTA website (www.aafta.org) under the Free Downloads link. The website also has this difficulty rating system posted on it for future reference. I would encourage all clubs to use the rating system when planning their courses and report the course difficulty in their write-ups. That will allow the rest of the Field Target community to more accurately compare match results. If there are any questions about the difficulty rating system, please feel free to contact me about it.
"Brad Troyer
AAFTA Chairman"
A Team PCP Tuning Document
(please note the site does go down with high
traffic so check back if it isn't available)
