I aquired a 7MM Mauser at the beginning of deer season. I believe the scoped was knocked out mid season leading me to miss two does. I finally had to borrow another gun to put some meat in the freezer. The gun was originally sighted in with re-loads. I've been advised it's best to use factory bullits to sight in and hunt. Do you all have advice on what brand, type of bullit and grain would be best for deer.
Also if you know a good online soucre that would be useful as well since mauser shells aren't exactly common.
Just like the old saying: "It ain't the bow, it's the Indian." There are reloads and there are reloads and it all depends on the reloader.
7X57 is a great deer cartridge. In fact, I've seen a bunch of folks say it's their favorite. I've shot it, but never at a deer. I can't warn you about anything in particular, but I will give you a few general hints.
The only problem I see with reloads is the reliability of the reloader. I reload, and I spend a lot of time custom-tailoring the load to the rifle. In fact, I haven't shot a deer with a factory round in 15 years. However, I don't do reloads for anyone else except my nearest kin. For one thing, it is a liability issue and for another, if you are not involved with the shooting, then reloading becomes rather dull.
The main issue comes back to reliability. You want something that will punch the paper at a reliable place, so you can set your scope to put it where you want. You may be able to achieve that with your buddy that reloads for you, in which case I would recommend bullets like Hornady Spire Points or Remington PSPCL's or some bullet of that ilk. Load well beneath the MAX load and see what works. Deer are not that hard to kill, so staying 2-5% off the MAX will probably produce an accurate round that kills deer, and is very easy on the shoulder.
If you decide to go the factory route, start cheap and work up. Try what you can find locally. Deer do not need fancy bullets. Start with anybody's bottom-end soft-point ammo and work from there. Stay in the middle of the road on bullet weight. It does not matter exactly where you start, but something in the 130-150 grain range is going to be fine. Work out from there until you find the one that shoots most accurately and most reliably, then go buy a bunch of it and be done with it.
Sources? Grafs. Midway. MidSouth come to mind first for ammo and reloading components. However, if you should be able to walk into a good sporting goods store and ask for 7X57 ammo.