GURPS ULTRATECH ballistics?

[HANS]

Originally Posted by hal

Looking at the real world data on the Rifle round for the G11 4.73x33mm round, the weight of the bullet is 3.1 grams (49 grains) and the weight of the round is 12.05 grams (186 grains). That produced a round velocity of 3051 feet per second or 930 meters per second.

No. The total weight per shot of the 4.73×33mm DM11 is 5.2 gram (0.01146 lb, or WPS 0.011 as per HIGH-TECH, p. 176). This is per Seel DIE G11 STORY (1993) and Kersten/Schmid HECKLER & KOCH (1999). I'm assuming both are not available to you, both being in German. The former is the ONLY book on the G11 and nothing but the G11. The latter is the official history of H&K. The authors of both had access to the weapon and ammunition.
Further, you are reading Hogg MILITARY SMALL ARMS DATA BOOK (1999) wrong. The "186" on p. 275 line 2 column 8 is NOT the weight per shot, but the bullet diameter in 1/1000 inch.
Frankly, this is also obvious from the facts. If the bullet weighs 3.2 g, it is extremely unlikely that the whole caseless cartridge weighs 12.05 g. Because then it would weigh just as much as a cased cartridge (compare the 5.56×45mm M193, which has a 3.63 g bullet and weighs 11.79 g overall). Caseless cartridges generally halve overall weight ...

Cheers

HANS