300 wm dies

Something I don't know if it's been mentioned is to expect Lapua, Nosler, Norma, shoulders to push forward about 0.012" before the case shoulder contacts the chamber shoulder. The only one that doesn't do this is Peterson 300 WM Long. It is not a problem as you are headspacing of the rim. It can make you scratch your head on load development as you case capacity grows until your shoulder bumps. After your shoulder bumps just bump it back .002-.003 as you would with ant cartridge. The .012 is with a custom match chamber. Redding technicians have told me they have seen it take 5-7 firings in a factory rifle.
 
So, the 300WM is a belted magnum and since generally we no longer headspace off of the belt a bulge will start to form at/above the belt after a few resizings. This can eventually cause problems chambering resized brass. There is a specialty collet die that corrects this and that is really the only thing I would add to the thread. LarryWillis.com is where you can read about or get the die.
 
I too reload 300 WinMag among several other calibers. From reading your replies, I see Redding dies regularly suggested. Can anyone help me decipher any issues with RCBS dies? They seem to work for me across many calibers, but am I missing something here? Thanks
No issues work perfect. Just buy the standard set and go to work.
 
like reelamin said, standard dies will work for most guys. If you have neck tension issues than bushing dies may be in order.
Another option is skim turning the necks; I do this for my 7rum and it works well. I've got a rather tight necked chamber, and you NEED a couple thou. clearance to release the bullet properly. RP brass was varying a bit in the neck, so I started skim turning to get clearance.
 
I know this is a slightly older thread, but I'm struggling to find exact processes for loading for the 300 WM I have.

Rifle came with a body die, bushing sizer and comp seater....

When do I use body die? Why not JUST neck size?
 
I know this is a slightly older thread, but I'm struggling to find exact processes for loading for the 300 WM I have.

Rifle came with a body die, bushing sizer and comp seater....

When do I use body die? Why not JUST neck size?
Do you mean a FL sizing die?
 
Use the body die to bump the shoulder back and ensure smooth feeding. It might not be necessary every loading, your gun and calipers will tell you. Size the neck after the body, do that every loading even if you don't use the body die.
This makes perfect sense now that I'm reading it...

And, all the dies make sense now too.
 

Attachments

  • 16817847877405819913700915319207.jpg
    16817847877405819913700915319207.jpg
    1.2 MB · Views: 53
You have 2 good dies. Seating die for bullets, and a neck neck bushing sizing die for 300WM cases. Belted mag have stretching problem, and the case separate fairly quickly at the base. First thing you need a paper clip. Straighten it out and make a sharp point at one end. Make a short bend at the pointed end. That paper has to fix down the case neck to reach the bottom of inside of the case. By pulling the paper clip up and down just a short distance you'll feel the point catch on something. That something is the starting of case separating. Remove the case from you reloading cases. It's seen better days.
You need a reloading manual. I would suggest Sierra Reloading manual. It generally has a larger selection of cartridges. I would get others too. Need to read about reloading as the first step or get help from a friend.
Neck sizing bushing die that a good die to have. You can set neck tension with different bushing. Depending the thickness of the neck of the rifle case and the bushing you use.
You are just barely getting started and you need lots of other equipment.
Manual first thing! Read the 2nd thing!
 
You have 2 good dies. Seating die for bullets, and a neck neck bushing sizing die for 300WM cases. Belted mag have stretching problem, and the case separate fairly quickly at the base. First thing you need a paper clip. Straighten it out and make a sharp point at one end. Make a short bend at the pointed end. That paper has to fix down the case neck to reach the bottom of inside of the case. By pulling the paper clip up and down just a short distance you'll feel the point catch on something. That something is the starting of case separating. Remove the case from you reloading cases. It's seen better days.
You need a reloading manual. I would suggest Sierra Reloading manual. It generally has a larger selection of cartridges. I would get others too. Need to read about reloading as the first step or get help from a friend.
Neck sizing bushing die that a good die to have. You can set neck tension with different bushing. Depending the thickness of the neck of the rifle case and the bushing you use.
You are just barely getting started and you need lots of other equipment.
Manual first thing! Read the 2nd thing!
I'm good on all the reloading processes in general. Just no experience with belted mags other than loading some .257 RoyW for my Dad when he used to still hunt some. But we just used a Lee collet neck die that I had gotten for .25/06...

Also never used a bushing neck die, but it makes sense now.
I think I may have the same type of die for my 6.5 CM also...
 
I'm good on all the reloading processes in general. Just no experience with belted mags other than loading some .257 RoyW for my Dad when he used to still hunt some. But we just used a Lee collet neck die that I had gotten for .25/06...

Also never used a bushing neck die, but it makes sense now.
I think I may have the same type of die for my 6.5 CM also...
Nothing wrong with RCBS dies. I use them for years. I had changed to Redding bushing dies a couple of years ago. RCBS wasn't make any that that time. There is others that make bushing dies too.
I would go to a depriming die. Get away from the expanding ball in the dies.
 

As mentioned in a previous post, you will want this to extent brass life of belted magnum
Interesting equipment. I figure out how extend the life of belted mag about 25yrs ago by using a neck sizing die. Now there just bumping the case shoulder should also to the trick. I have used it yet to see how it works out.
 
Top