Re: Acceptable Tactical Rifle MOA?
Some nice shooting above. In thinking about this, though, I'll paraphrase HATECA re. What kind of tactics?
For the military LR shooter, at N-1000 yards+, an MOA or better rifle keeps all the shots in a torso. Perfectly acceptable battle accuracy and even if you no-kill a target, you may get a chance to tag his buddies when they come to help. I think most military issue sniper rifles are sub-MOA these days anyway.
LE M/O training (and most actual shots) tend to run about 75-100 yds in urban areas and out to about 300 yds in rural areas (much less common than urban engagements). And the LE precision marksman must be first-shot, cold-bore accurate every time. Accurate should mean central nervous system stop (T-slot, Medulla Oblongata, etc.) at any range where a shot can be taken. You have to know your equipment and own skills, especially if training for an environment where there may be civilians or over-penetration risk, etc. Our qual is cold bore shot within 1" circle every time at 100. Similar results expected to max of 300. There is a lot more to the quals than that, but the 1" cold bore is the 'key' shot. In any weather, heat, cold, wind, rain, snow... My personal goal is to shoot 1/2MOA out to 300. My rig and ammo can do it when I can. I have shot to 800 at schools, but beyond 300 is not in our ROE, so training focuses <300.
I can't speak to competition shooting standards, because I've never done that. But expect competitions are very demanding, accuracy-wise. I would think that top competition shooters would want at least 1/2 MOA rifles (or better), no expense spared because that's a competitive edge. But that's a guess as to acceptable accuracy there.
Finally, my focus above on the LE is because it's what I know and it isn't to say that LE shooting is more demanding than military or competition... the military shooters I know are out-of-this-world skilled and practice more than we LE guys can dream of. And work in an really, really dangerous and demanding environment. They are the varsity, IMHO and for some specialized shooters, the standards are way above what is demanded of most LE. And from what I gather 'sniper competition' shooting is as demanding as all get-up, both in terms of shooting skill and athletics.
Anyway, my thoughts re. what is acceptable all hinge on need/application first, then determine what's acceptable in terms of MOA accuracy to meet that need.
Just some thoughts. Cheers, Sirhr