Originally Posted by BloodSport
One thing to keep in mind when it comes to Airsoft Sniping, and that your from Ontario. Is that a lot of the groups and game organizers will not let you use it unless your certified by one of the Airsoft Sniper courses that are periodically run.
Sorry I'm out in the west so don't know about Ontario games but does that apply to people that want to use "hot" sniper rifles or all sniper rifles (ie. under 400 FPS or game limit).
OP: 400 FPS (on .20g BB) is where you generally want to be sitting at or so I'm told, you also bring it down even further by using .30g BB's, increasing effective range and consistency/accuracy but lose speed from the projectile.
As for what to start with, everyone has their own opinion but I would honestly start with something of higher quality right off the bat. It doesn't have to be a $700+ rifle but something like a $350 rifle will be awesome as a starter and stepping stone.
If you really want a DMR that you can play with right off the bat. Then Classic Army has a "SR-25" (model name CA25) and IMO that's pretty much perfect externally, but it does come in at a hefty ~$650 + shipping and internals aren't as great as they could be (but then again, the internals aren't crap like they were 5-6 years ago). As well since they're "7.62 mags", they'll be slightly harder to find and more expensive as well. OR Maybe you decide that something in the $400-500 range is more like it. Note that all the ammo in airsoft is the same size you don't get any benefits of having an AK or M16 or MP5 or whatever, what really matters then is the internals and how much consistency they provide in propelling a BB out of the gun.
There is also the option of buying used from the classifieds system. You might be able to find a good "starter package" for $600 or so (which might include extra mags, optics, extra battery, possibly a charger, half a bag of BB's, etc.).
Only other suggestion is that you should get a gun that's relatively more "common" like an M16 or AK if you're starting out due to plenty of parts available for them and mag compatibility as well (ie. if you need to borrow a mag for your first outing it's not some obscure one like a 7.62 mag).