The differences between the IPSC target and the Paladin target is that the A-zone continues all the way up to the neck line and that the angled bottom lines of the C-zone continue down to the botton edge of the target.
The A-zone difference is probably the most important as Rick Miller and I both think that a hit in that high chest/throat area would probably be pretty decisive and ought to score a 5.
We used to have a die to produce the proper Paladin target, but the machinery it was used on is now obsolete and we’ve never bothered to get another one made. It is easy enough just to use IPSC targets and score that little neck strip as a 5.
IPSC president J P Denis contacted Rick about adopting the Paladin target back when IPSC was moving away from the “item” and “option” targets. Rick said okay. However, IPSC changed the target slightly (as noted above) and Rick suggested that they call it something other than “Paladin”. They called it the “Brussels” target until it became so ubiquitous that it simply became the “IPSC” target.
All this said, the scoring zones of a target are a guesstimate and a compromise at best. The Paladin target is as good as any IMO. However, the more important thing is the Paladin scoring system itself. The Paladin scoring system requires that each hostile target have either an A-hit or hits totalling 7 points to neutralize the targets. A 5-second penalty is assessed to each target not neutralized. Thus low time wins. This system permits the shooter a great deal of freedom in how he attempts to solve the problem. It also allows shooters of low-capacity weapons (revolvers and such) to compete with higher-capacity pistols. In a real-world situation, I suspect we would all approach the problem differently if armed with a J-frame versus a Glock 17.
An added plus is that scoring/adminstrating is easy. No meaningless point totals to keep track of, simply elapsed time plus penalties.
The Paladin scoring system works great for scenarios that mimic common defensive usage of the pistol. It works less well for “assault course” track-and-field-with-a-pistol stages, as are common in IPSC. Like Comstock scoring, it can overweight fleetness of foot in these cases.
The “Vickers Count” scoring system used by IDPA was influenced by the Paladin system as well. Rick Miller and Ken Hackathorn (one of IDPA’s founders) are friends from way back and have discussed combat pistolcraft and combat pistolcraft taining and competion many times over the decades.
I take some pride in having helped Rick develop and refine what became the Paladin scoring system over the years. I was mostly a lab rat in the process.