am I late?
I'd like to second the above, and to add--
You wrote, "Can a non-sporter Nagant be used?" I'm presuming here that you're asking because you already have one. If your local regs don't require shotguns, sure. I have a Mosin-Nagant 91/30. A "sporter" is just lighter and handier than a full-stocked military rifle. It might fit you better, it would be easier to carry for long distances, and it would likely have a lighter, smoother trigger. None of those are overwhelming problems {wait, let me put my firefighter's turnout gear on; I might get flamed for saying that}. Going hunting with what you already have is wonderful; it's miles better than not going.
Your full-size M-N might make it easier for you to hold steady with a deer in the sights. My heart pounds when it's time to take the shot; YMMV. The rifle's weight will soak up some recoil, too. Your rifle will have more recoil than some other deer rifles. Some big, tough guys hate recoil and some teenaged girls hardly notice it; there's not much of a pattern.
The 7.62 x 54R is in the .308/.303/.30-'06 class; these are higher-velocity cartridges than the .30-30s that have taken so many deer, but a very, very popular group of deer cartridges. Be sure to buy some good-quality hunting ammunition (Sellier & Bellot is one of the manufacturers of hunting cartridges in 7.62 x 54R, IIRC). Practice with it before you go hunting; know where your rifle groups with your hunting ammo. You DON'T want to use "hardball" (Full Metal Jacket) ammo for deer, ever.
I'm a big fan of taking the shot from as short a range as possible. Waiting, or sneaking closer, will tend to pay off. Use a tree, fence post or other rest if one is available when you're ready to take the shot. That's good sportsmanship, not poor sportsmanship. Ethics demand that one do everything that's possible to achieve a clean kill.
"If you can get closer, get closer. If you can get steadier, get steadier" (Col. Jeff Cooper).
Also, it's called hunting, not the long-distance championships. Practice beforehand to have a good idea of the distance at which you can hit reliably. Ignore the distances claimed by others; they're not taking your shot. I'm proudest of the shots I have taken up close; they mean I'm a hunter, not just a blaster. No offense is intended here to those who can reliably take long shots; getting close is a big thrill for me. I've shot highpower competition a couple of times, and my favorite stage is at the 600-yard line. I'd never try a shot at an animal at anything remotely like that distance. My favorite hunting shots have been those I've taken at 15 to 75 yards. Closer is better.
Get a simple, ordinary sling that feels comfortable to you. It doesn't need to be fancy or expensive. As a somewhat edge-of-the-curve example, my rig in very cold weather (hunting with family in the midwest, heavy woods, small, steep hills, and snow) is a piece of rope on a lever-action carbine. The rope works well on the heavy, insulated orange coveralls that I wear there. Does it look dorky and homemade? Sure! Do the deer notice? Nope.
Have someone show you the "hasty sling" method, and the easier ways to sling up from common carry positions. My M-N's too long for me to feel comfortable with "African carry" - rifle with muzzle down, behind the left shoulder (I'm right handed). I like African carry with carbines, and I'm tall, and I STILL watch the muzzle when I move, bend, crouch, walk on a side-hill, and ...
Some people don't like to use a sling when standing. I do, especially with the tree or fencepost that I mentioned above. A simple, ordinary sling is also good to have to carry your rifle across your back while you're hauling your deer (with tag and blaze orange attached) out of the woods.
Study deer anatomy. Talk to other hunters (especially older ones), maybe in your basic / hunter safety class, and to game officers. Find out about how the vital areas (especially heart, lungs and liver) of a three-dimensional deer look when it's broadside to you, or quartering away, and so forth. Understand that a fatally-hit deer can travel a ways; be prepared to follow until you find it. Expend every effort until you've located a deer you've hit.
NO WHITE CLOTHING! Especially no white handkerchiefs, no T-shirts visible at your neck, or the like. Even underwear - make sure that you cannot show a flash of white. Almost all hunters are fine people; that's irrelevant. It only takes one clown who doesn't follow safety rules to cause a tragedy and feed the anti-gunners. (and I presume that you follow the Four Rules). [*steps off soapbox*] Remember your blaze orange and don't hesitate to wear more orange than is required. Deer don't have good color vision; they're great at seeing movement.
It doesn't hurt to take an extra, empty gatorade bottle to pee in instead of watering the bushes; a deer's sense of smell is acute, too. Yup, tear off any bottle labels with white on the back. A game officer here told me last weekend that a guy had once been shot in this state when he opened up a pack of Marlboros (in that instance, he was turkey hunting: don't want to wear white, red, black, or blue then - they're the colors of a turkey's head).
Water, a little extra food, and whatever's appropriate for being outdoors in a possibly-unfamiliar area (OT, but easy to find out). You didn't mention whether you're experienced in the woods. If so, you already know to tell someone where you'll be, and when to expect you back. Above all, keep asking questions, just as you're doing here. Different locales, different preferences, people who've had different things work well for them: it's all grist for the mill, and will help you to choose what works best for you.
