Thanks for all the advice in the past. Here's a couple more queries:
Firstly, I don't know if this is an ammo question or a gun cleaning question, but I've noticed recently, when punching paper targets, that a few shots have landed a good 8 inches below the point of aim, despite the rest of the group being good. This has happened 3 or 4 times, and the last time (last night) I actually saw the flight of the bullet through the scope, following a strange "S" shaped path before hitting way below target. These have all been from the same batch of ammo (remmington hollow point subs), but, interestingly, have also all been the first shot of the session. So, is this an ammo fault, or dirty barrel, or what?
Next thing: Thanks to Dave (223) my scope is nicely zeroed at 50 yards, and I'm now able to consistently place groups in a 1 inch target at that range (with the exception of the odd-balls, as described above). Using the Hawke software, I've worked out the intervals for the dots in the reticle, the first being 65 yards. At that range the group is a bit bigger (2.5", on average), but still a dead rabbit! However, moving up to the next dot (80 yards) I'm lucky if I can get them all into a 5" circle. They're also noticabley all landing to the right of the point of aim at that distance. Given that the scope appears bang on at 50 yards, should I tweak the windage adjustment to correct what's happening at 80 yards, or just do more practice to tighten the group at longer ranges?
Also can anyone give me any tips on estimating range in the field? Was out rabbiting a couple of night ago, having done a recce of the land first. Set myself up at a known 50 yards from a hedge end, with a bank behind, and every bunny that came out onto that bank was a dead one! However, after a while I noticed rabbits coming out to feed at the other end of the hedge, at right angles too my position. I hadn't measured this distance beforehand, so was trying to guess range, and missed all shots.
Also, can someone please explain, in laymans terms, the relative merits (or otherwise) of HV .22LR ammunition, as opposed to standard subs.