I don't get why you're so dependent on the numbers it might give to the weapon, I don't get why you have so little faith in the textual description of the item. The Damage Rating into is already mostly a footnote/submission tax to most articles.
This is honestly the sentiment that I agree with most. I started work on this project simply because doing the math with the old/current DR system was a hassle, and no one used them as the system described anyway. Beyond that the old DR system didn't give at all a clear idea of how effective something was without having to calculate the ROF whether by a 10 second increment, or trying to determine how much damage a single round was doing then multiplying the DR value by the ROF, and then comparing it to the SP for an idea of how effective something was. I honestly got nothing out of the structure of the old system.
With this things were simple enough, one Class, if shot by the same Class will probably die on a direct hit. A lower class weapon, will take more and more time/effort/luck to succeed due to being a weapon ill suited for the purpose that you are using it for, and a higher Class weapon will be more effective due to the effects of killing a mouse with a rocket launcher.
To this end the numbers were at most a reference point for me. They weren't a part of a mechanical system, there was no stats, merely reference points like those found in an index in a book. You don't look at p.125 in an index and think that it has any mechanical value. To this end, a Class number was just a fast way of gauging where on the table something was. Beyond that I wanted to focus on the parts of an article that the author actually spends time one, like the function, form, and the way they describe the effect of the item. The only thing this was supposed to do was give you an idea what all of the fancy text was supposed to achieve, since I'll be honest going by hard science, most weapons don't hit hard enough for what they do, and ignoring hard science you're left with a really fancy weapon effect and no idea if it'll kill an unarmoured man, or obliterate a star fortress.
I went along with expanding the examples from three to five, not because I felt it was truly necessary, but because I wanted to manage to get the old systemic mess of numbers and math out of the way in favor of a much simpler reference guide. If people were going to boycott it on principle then that wasn't going to help me in the long run. So I took what I felt was a relatively simple step and added a couple slots to each category since it made people happy.
Now however, it seems that most people are getting hung up over the numerical value of a weapon and insisting on the statistic value of an item, instead of asking themselves, "How is this supposed to function? What am I going to regularly be killing with this weapon? What are its main applications?"
I get that
@Koenig808 wants the HPAR to be the answer to the SAoY's ASBR, it makes a lot of sense given that it was even designed to disable zesuaium clad enemies by locking up their joints and weighing them down even if it couldn't penetrate. This was a weapon designed to defeat some of the most dangerous foes of the setting at the time. As it stands it also functions like an explosive penetrator, being a stream of molten high velocity metal, a concept that we use IRL in anti-tank weapons. So to me it isn't surprising that it would put holes in most targets, especially if their armor is at most 6-8cm thick.
However
@CadetNewb is set on an effect of splattering the enemy with metal, yet is completely against using a less penetrating ammunition type (for reasons that elude me) and wants an effect similar to a gun based
LAG Grenade. Beyond this they have also expressed disdain that the "standard issue" weapon for every marine is powerful enough to make short work of lighter PA targets since it makes narrative encounters too decisive.
In this case, given the way that the weapon is written, and that Nepleslia, has spent most of its history having to worry about zesuaium clad foes, be they old style Yamatai power armors, or Mishhu, I can see why they would want their standard issue gun to be lethal. I believe
@Fred encountered a similar problem during his threads which lead to the development of the LASR, giving his players a weapon that allowed for more drawn out combat compared to the ASBR, and the Daisy Plasma Rifle with the justification that it would damage the inside of friendly ships less.
Unfortunately it seems that Neplesla's LASR the LCA is distasteful, for reasons that I am not old enough to know. Also at the same time using a less penetrative/less damaging version of the HPAR rounds is also not acceptable, so we have a case where a GM is upset that a weapon that is interesting to use is taken form their hands due to miscommunication, and the FM revelation that it hits harder than the GM wanted.
So I guess that covers the "why" of the HPAR, since its targets were traditionally much more dangerous foes than the presently common lineup of PAs and units. It's a weapon of the ASBR's age.
Moving along...
From what I understand, the reason there was complaint about mixing .50cal and 20mm rounds is that the latter has much, much more kinetic energy than the former. A .50cal round to my knowledge will potentially kill someone due to shock even if you hit their limbs. A 20mm isn't likely to leave much that is recognizable by way of a limb, because it has much more propellant and a round of a greater mass. To this end a 20mm would disfigure and ruin a car, were you to shoot a human I do not believe that survival would be likely unless you clipped them, or hit an outer extremity like a hand, maybe. Those who know more about firearms can correct me if I have made a mistake here.
While the above stands, I personally didn't care about having them in the same category, since I am of the opinion that were I to read two weapons of the same class, if the author bothered to write any fluff, I would know that the 20mm round would be much more effective on soft and materiel targets than the .50cal. I would also know that the 20mm is harder to carry around due to being bulkier, and for the average soldier they wouldn't be able to carry much. So even if by the old table they were both Class 3, I would know that while they will both kill a man, and not quite pose a lethal threat to a PA, that the 20mm is the much more effective of the two. Since I would be basing my decision off of the weapon fluff, and not the Class.
To this end, having 3, or 5, Classes per category means nothing to me. I interpret them the same way, and I would fully expect that even with the expanded table that there would be weapons with different effectiveness within the same class. After all at most basic I would treat a plasma weapon as more dangerous than a kinetic round, since even if the plasma weapon misses you, you can still be burned by the heat, where as a 20mm round that fails to hit you will mess up what it hits, instead of you. To this end if you had a kinetic rifle, and a plasma weapon both sitting in Class 5, I would choose the plasma weapon for if I wanted to be sure my target dies, and the kinetic weapon for situations where I want any sort of precision, especially among a crowd.
Basically at the end of all of that wall of text, for the tl;dr I just want a reference that tells me what a single round from my gun will probably kill. I don't care about fussing with ROF, or any of that within the DR page itself. I want weapon authors to tell me how their gun works, not the global submission tax system.