XM274 Revisted And Edited

Gun Stats says it can do cannon.  In fact, they give us the detailed process of making the 120mm M256 firing the M829A3 APFSDSDU round.

So I decided to see if the numbers I pulled out of my ass for Twilight 2000 were even close.

The initial APFSDSDU round did 6dx19(2) pi++ inc out to 4,800/16,600.  This round didn't last long in testing and never got an XM designation.

XM885 (Delta 3) APFSDSDU round did 6dx25(2) pi++ inc out to 4,800/16,600.

XM885 (Delta 6) APFSDSDU round did 6dx28(2) pi++ inc out to 4,800/16,600.  Delta 6 might have become M885A1 if development had continued.

XM884 HE-AB did 6dx11(0.5) pi++, follow-up 6dx3 [4d-1] cr ex out to 2,400/8,300. 

The penetrator is 19mm in diameter and 380mm long, so it's definitely a long-rod with its 20:1 LDR. 

Gun Stats says a long rod penetrator APFSDSDU should do:

XM885 does 6dx25(2) pi+ inc out to 9,340/30,600.

XM884 does 6dx12(0.5) pi+, linked 6dx3 [4d-1] cr ex out to 4,670/15,300.

I get more range, regardless.  I'm giddy how close my original XM884 round was and I'm happy that the calculated damage matches the published penetration values for the Delta 3 round.  Not sure how to get it to spit out the published Delta 6 values, except for the section on page 23 saying to just calculate the damage off the actual values rather than the what the formula says.

The delta 6 is calculated as a "long rod" round, delta 3 was not, but there's some speculation that it was also heavier than the delta 3, which could up the damage.

If delta 3 was always a long rod and 6 is heavier...  But I don't think that 2.91kg is realistic.

Acc changed from 8 to 5+3.  ST changed from 70M to 62M.  Rcl changed from 10 to 4. 

I think I can live with these numbers.