Based on the numerous informative replies I've received in the African Hunting forum, I've pretty much decided to go for a .300 Win Mag as my safari rifle. I've read/heard various oblique references to problems associated with reloading a belted cartridge. What are the pitfalls of reloading for the .300? Are there any particular steps I need to be aware of or that are different from loading say...a 6.5 X 55?

Enlighten me please!

I reload for my .300 Win. Mag, as well as for other calibers which are not belted magnums. I have not experienced any problems in reloading for this cartridge. I find it easy to do. I full length size the cases initially, before the first use. Then, I neck-size them on subsequent firings using a Lee Collet Die. This way, they headspace on the shoulder rather than the belt, and do not have to stretch so much on repeated firings. (Every 4-5 firings I have to full-length resize them again.)

There ain't nuthin' magic about loading a belted cartridge!

It's just like loading any other bottle-necked cartridge...

I agree with BigBrass. I neck size as long as the round enters the chamber easily, and then FLRS. I am not sure this results in longer case life, but it is what I do. I do not hunt with any case which has been reloaded more than once, and normally use new cases for hunting. In your case I would load new cases for the actual hunt.

Since the belted round headspaces on the belt (until fireformed), some manufacturers have been sloppy in the chambers as opposed to the non belted cartridge chamberings. This leads to a shorter case life in theory at least. I believe it is correct as my belted cases do not last as long. That may be in some measure due to the fact that I load them pretty hot. I don't buy a 300 Wby to get 30-06 velocities.

There are really no problems reloading a belted case. Use the same care, and it will go well. The .300 should be a fine choice for your hunt.

Jerry

I resize my 300WM by headspacing off shoulder rather than belt. For my guns I shot 3 NEW bullets then measured with RCBS precision mic and set FL sizer die 2 thousands back from shoulder. This makes every bullet chamber. Reloads fit the chamber.

The only potential problem with a belted mag is having a sloppy chamber, and then over working the brass. Other then that, no different then any other centerfire.

I think you'll be very pleased with your win mag. It's the chambering that is on the short list of future rifles to be built.

Desertram:
You'll like the 300 Win Mag. What causes short case life on belted (or non-belted) brass is overworking the brass, whether due to oversized chamber or whatever.

I get very good brass life with pretty warm loads in my factory (Mod 70) chamber by adjusting the sizing die to just barely touch the shoulder, essentially making the FL die a neck sizer. I like to feel a very slight resistance as the bolt is closed. This allows you to headspace on the shoulder rather than the belt, works brass very little, results in better accuracy and longer case life.

Regards,
hm

This is the best set of comments I've seen on loading belted cartridges. I agree with everything said here.

Simply remember, your rifle is a bit different from every other rifle, and if it is a factory chamber from one of the major manufacturers, it may very well have a somewhat oversized chamber. If that is the case, you may find that your FL die reduces the shoulder DIAMETER (as opposed to base-shoulder length) a bit even when backed off to "neck size" only. This is not a problem, so long as you size only so much as to still allow the case to properly headspace on the shoulder. For hunting rounds, you may wish to "bump" the shoulder back very, very slightly in order to assure effortless chambering.

The problem that belted cases have is that the chamber dimensions are all on the plus side. So when the case is fired for the first time it does some damage to the web (near the base). This damage is more than what happens on a rimless case and may range from hard to detect to a deep ring inside the case in just one shot.

So if you need to take special precautions or not does depend on what your luck of the draw is on your belted chamber. This is why John Ricks offers to take special care on his custom rifles to avoid this concern.

Most reloading manuals go over this head separation problem. Some do it in detail and the RCBS Case Master comes with a feeler gage to check for this. You can make your own however.

This can happen with any reloaded cartridge of any type in any action. But belted and rimmed cartridges are the worst designs. Also actions with rear locking lugs cause this problem.

The firing pin should be removed from the bolt if possible and the FL die set to get the sized case just right.

For a big hunt new brass of once fired brass should be used anyway and this reduces the concern.

Good luck and be careful.