Problems sizing the 300 Norma Magnum, Shell Holder??

[nnnn16]

I recently worked through all my once fired brass and ran into a problem with the resized loads. Some of the cases load fine and some of them won't even let the bolt close. They were all treated the exact same and put through the exact same sizing die. My first thought was that some of the cases stretched and needed to be trimmed but after measuring the ones that load vs the ones that won't, that isn't the problem. I got to looking at the cases and noticed weird marks from the shell holder. From the marks, it appears to be pushing on the bevel above the base instead of the base of the case when I'm sizing them. I might be wrong but it seems like this would probably be the problem because the cases aren't all being pushed into the die exactly the same and the ones that are going in less would then be just a hair bigger around.
Then I remembered that when I was originally looking for a shell holder to load up my original rounds I couldn't find one in town. Knowing that the 300 Norma is based on the 416 Rigby I tried that shell holder and the "Lee" fit so I went with it. It's obvious now that I need a different holder but I don't know which one to get. The one at my local store that is supposed to be for the 338 LM doesn't fit, nor do any of the others (on hand) that the book says should work. Has anyone else run into this and what did they get figured out. I'm using Norma Brass, and I have a Rock Chucker Supreme Press. I'm sorry if this has been covered before. I know it pisses some of you guys off when things get repeated. I found some threads on the subject but I never found a definite answer for using the Norma Brass.

Please and Thank You
nnnn16

 

[BobinNC]

I looked and it appears that RCBS #48 is recommended for both the 300 Norma and 338 Norma. Since the 338 Norma is the parent of the 300 Norma, that one should work. There is no compatible shellholder made by any other company, other than RCBS #48, that appears to fit.

From the Midway USA Reference chart only lists this :

300 Norma Magnum

RCBS #

48 Ref No. 928-820

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[bigedp51]

Bingo, six shell holders listed for the 300 Norma Magnum at the link below.

Rifle Shellholder Cross Reference Chart

 

[BobinNC]

Bingo, six shell holders listed for the 300 Norma Magnum at the link below.

Rifle Shellholder Cross Reference Chart

Not so Bingo, because they are all incorrect in that listing. Those shell holders fit the older 308 Norma magnum not the newer 300 Norma. So it's a typo. Not your fault that they did not label it correctly.

But you can tell because they list the exact same shell holders for the 300 H&H, 300 Win Mag just above it, and the 300 Weatherby Mag just below it, and the 300 or 338 Norma case head is way bigger than the standard magnum 300 H&H size case head....

 

[bigedp51]

Thank you BobinNC for the correction, you just proved you can't Google everything.
(mumbles under his breath "I hate it when the Marine Corps is always right".

Aim High, Air Force, Military Airlift Command, Yokota AFB 69-73
Survived two TDYs to Iwacuni MCAS and the Marines didn't kill me.
But the Gunny wanted me to get a hair cut.
The Marine Air Wing guys were a great bunch but they kept stealing our ground support equipment
for our C-141s and blaming the Navy. We were at Iwacuni air lifting the Marine F-4 Air Wing to Bien Hoa Viet Nam.

 

[BobinNC]

I was never a Marine, actually I'm a US Coast Guard Veteran 1969-1973. Member of USCG Squadron Three, RVN 1970-1971

 

[bigedp51]

Now I'm really confused, your profile says "Gunny Sergeant" and that rank in the Coast Guard would be Chief Petty Officer.

Never mind I'm asleep at the switch, I just noticed I'm a Private and we have ranks in this forum.
This sucks, I was a Staff Sergeant in the Air Force and this forum busted me to Private.

 

[BobinNC]

Now I'm really confused, your profile says "Gunny Sergeant" and that rank in the Coast Guard would be Chief Petty Officer.

Never mind I'm asleep at the switch, I just noticed I'm a Private and we have ranks in this forum.
This sucks, I was a Staff Sergeant in the Air Force and this forum busted me to Private.

The ranks where based on your post count. After the last board upgrade that ranking system sort of went bye bye as many post counts got lost or were dropped. I guess I could change it to something nautical now, but it's not important enough to bother me. It is what it is...

 

[vh20]

nnnn16,

Mr. Sloan, who developed the .338 and .300 Norma Mags (which share the same parent case), has said that he uses the following shell holders (this was in regard to the .338, but there should be no difference, and I actually copied/pasted this from his post):

Redding Shell Holder #35
Lee Universal #8

 

[BobinNC]

nnnn16,

Mr. Sloan, who developed the .338 and .300 Norma Mags (which share the same parent case), has said that he uses the following shell holders (this was in regard to the .338, but there should be no difference, and I actually copied/pasted this from his post):

Redding Shell Holder #35
Lee Universal #8

That's some good info. After your post I found this thread http://www.snipershide.com/shooting/snipers-hide-reloading/7471-338lm-redding-shellholder.html it's got some good data on the 300 and 338 Norma head size, and why Redding's #35 also works.

 

[vh20]

Very interesting, Bob. Good find.

 

[nnnn16]

vh20,
I appreciate the info. The Lee #8 is the one causing the problems though. I'll get the Redding and give it a try. I actually got in an argument with the local reloading "expert" just today, he insisted that the RCBS #14 was the one I needed. I just couldn't make him believe that his book was wrong. I felt so smart (new for me). Hopefully the Redding will do the trick. If not, I guess I'm gonna try and shim the Lee to see if it can be "rigged". It still blows my mind that there isn't more info out there for this cartridge. With virgin brass this thing has been fantastic. I have really struggled with getting consistent velocity though. I was hoping that uniforming my brass would help with that but now I don't have any brass that I can use. I can't tell you how frustrating that is. This has been my first attempt at building my own rifle and ammo, and until now it's been great. I'll let you guys know what happens with the Redding #35. Any advise or hints or help or mojo or magic you guys can offer with this cartridge would be greatly appreciated.

Thanks
nnnn16

 

[Mikiedem]

Did you figure out what was causing your problem? Asking because I just ran into the same problem.