I am planning on buying boxes of different brands and bullet types to find out which works best before I start reloading. That will give me plenty of brass to start with too.
Personally, I would try to stick to the same manufacturer of brass/ammunition to alleviate any concerns about internal brass dimension or case failure rate.
The M-N isn't meant to be a target rifle, but there is no harm in trying. I have had good luck with IMR-4895 and H-380 with Sierra 150 grain .311" bullets as well as Hornady 150 grain .312" bullets. If you are certain it is a Russian made rifle it most likely has a .310-.314 groove diameter. I did a ladder test with both .311 and .312 bullets up to the load manual specs and had no problems with a sticky bolt or even recoil for that matter. I have shot some old Russian surplus machine gun ammo in my M-N and the necks would split from the pressure! That rifle (M38 carbine) tried to split my shoulder with some of those loads too. I think that the load data out there is very tame to what the Russians were loading up. Of course, I was shooting them at 100F degrees + and the rounds were probably loaded up in anticipation of harsh winter weather.
If you can find Varget powder, that one did show me some sub-MOA groups out of a M-38 I have but not consistently. My dragoon won't hold a group with anything I have tried. I have a couple of 91/30's that shoot minute of pie plate with surplus and 2" groups with brown bear. I have settled on getting a 1.5" 100 yard group (handloads) as being satisfactory for my surplus rifles that may have seen more projectiles in the hole than a XXX star.
If I had the choice to do it all over again, I wouldn't have spent one penny on a Mosin-Nagant rifle, brass, dies, special bullets, or a trigger job, custom scope mount, aftermarket stock, and re-crown. You can save yourself a lot of headache buying an off the rack used 7mm magnum or 280 Remington and be able to shoot sub-MOA groups all day long with components you can find easily.
As far as pulling components and old powder and whatnot, I recommend you do it right. The M-N isn't as strong as it looks and a careless mistake may send some old scrap metal into places it doesn't belong. Be safe.
http://www.7.62x54r.net/
The above link has a lot of useful information regarding the M-N rifles. Good luck, and welcome to TheHighRoad!
