Dear diary:
Since the Omark 44 was designed for 7.62mm NATO M80 ball, that's what I'm going to sight it in with. Remington UMC makes a 150 grain FMJ (boat tail) that they sell around here, which is an M80 ball analogue; $20 for 20 rounds (reloadable brass, so yay). IIRC, most M80 ball analogues are 145 to 150 grains in weight, which is why I call 'em analogues; the original M80 round was 147 grains in weight and launched at 2,700-2,800 feet per second. All should be around that speed.
I don't know why there's a variation in weights there (haven't read why); countries are one of the main reasons I'm guessing, as being a NATO standard round they all made 'em, so jacket thickness and core uniformity might have needed to differ due to different tooling. Some behave differently terminally too; the German stuff fragments like a hunting round even though it's dead on at 147 grains in weight. Kinda defeats the purpose for precision shooting when they're all different weights, though. You can say they weren't made for such, but I recall they used M80 ball in all rifles, meaning sniper's and marksman's (and target ones). Until more recently, of course. Oz used a 144 grain round as the M80 equivalent (yep, the ret*ds had to be us); we probably still do.
I suppose all they cared about is that they were close enough and could function in each other's weapons when needed, as there's little in the way of 1 being better than the other as far as I can discern (other than Germany's fragmenting M80, which is something you wouldn't want to get hit with on the battlefield).
But whatever, that's just me talking to myself (all of this is). The UMC 150 grain should be fine to sight it in with. I do it at 50 meters, then take it out to 100 to make the final adjustments. From there on it's just simple math for what range you plan to shoot at and what adjustments you need to make.
O, and Gillian Anderson has always been my #1 crush. She's a Green, though, so we wouldn't get along at all.
This concludes my diary entry.