It isn't just about the bullet diameter, you have to consider the bullet weight and intended velocity. 7.62x39 usually uses a 139 grain bullet, the 7.62x54R uses 174 to 216 gr. bullet (depending on the age of the gun) WHY? Because the rifling has a twist , and different bullets perform best at a different rate of twist. Velocity also effects how the bullet perform in different twists.
Of your 3 guns that use .311 bullets, your best bet for a common bullet is a 147 to 150 grain bullet. It's a little heavy for 7.62x39, a little light for 7.62x54R and about right for 7.63x53. All 3 will use the same shape bullet, and can use Hollow Point (HP), Full Metal Jacket (FMJ), or Soft Point (SP) bullets.
A common Powder will also be a problem. The most likely candidate would be IMR 3031. A standard Large Rifle primer will work in most case of all three rounds.
Bullet trajectory will be a problem at distances from 200 yards on out (and maybe closer)
The 7.62x39 will be slow and shoot low to the sights (so you use a further distance setting).
The 7.63x53 will be pretty close.
The 7.62x54R will shoot high (use the closest setting, and learn to aim low!)
NOW ON TO 30-30 & 308,. If you buy 150 grain Round Nose Flat Point (RNFP) bullets made for 30-30 the will work fine in the 308 out to 300+ yards! The same Powder (IMR 3031) and Primers (Large Rifle) will work also.
7.92x57 is often referred to as 8x57. It also works very well with IMR 3031 and uses Large Rifle primers.
When times and supplies return to normal you will have all the equipment you need. You will want a different powder and bullet for 7.62x39. But IMR 3031 is a good to great powder for all 5 of the others! I have loaded 30-30, 308 , 7.62x54R and 8x57 with it and get exhalant accuracy that shoot to the point of aim with proper bullets! I have dies for 7.63x53 Argentine, but never had a gun to load for. For the others I started with Norma Ammunition and they have reloadable brass so I have about 200 of each.
If possible buy just one brand of dies, that way if something breaks, they will have many interchangeable parts. RCBS dies are well made, have a great warranty, and the best customer service! Hornady's current design has problems, and lots of breakage, but fair customer service. Lee has the lowest price point good warranty, and customer service, but remember; YOU GET WHAT YOU PAY FOR! Redding is one of the best, but expensive, Lyman makes good dies, but 1 year warranty and poor Customer Service.
On modern loading equipment, all brands are threaded the same (7/8-14) so they are interchangeable. I recommend a cast iron or heavy cast aluminum.
Buy the shell holder for each cartridge and leave it in the die box! The brands are interchangeable on this too. Lee brand do real well here and usually are the least cost.
You will need a good scale for this type of powder, a small battery powered digital with a pan will serve you well. (My brother and I have ones for trading gold and were $15 plus pan (I'm sure the price has gone up!), JUST MAKE SURE they will measure in 1/10 Grains.
Get a good loading manual! These are well established cartridges ,so a used/older manual would be just fine Lyman #45 from the 1970's is perhaps the best for your needs!
Have fun loading
Ivan
PS: You may notice, there are lots of opinions! They are like belly buttons, only yours and your mates matter! I notice some of the posts are by people that have no idea what they are talking about. Please be careful. ITB