1k tonfas(mine is at 10kills or less i think) 1k obli tech(mine is at 800ish) and 1k ultimate techs(think mine is at 600ish), from the forum i was reading seems this glitch was on the 360 to.
Ah and how do you check to see how many kills you have on each weapon?
word of advice if want to try the hard and very hard difficulty try to get all skulls(30) they will lower the meds.I'm playing hard and I cant keep more than 20k, hell in normal and easy i end up with over 200k.