.338 Norma Magnum & Norma Magnum Imp. Load Data

[bbhank]

The current .338 Norma reloading thread is broken and cannot be repaired. So Frank told me to start a new.

I am brand new to this and build a .338 Norma Rogue Improved and will be fire forming brass with Lapua Brass 87.5 grains of Retumbo and 250 Grain Berger 250 Grain OTM's

Stay tuned for more!!!

 

[Moses42ak]

There was a lot of data in the last thread. Hopefully those who contributed will chime back in.

 

[Mareshow]

Bump would love some data with N570

 

[Castloader]

I’m looking for data to deconflict different sources for a max load. I’m using 300gr Berger OTM with Retumbo. Standard SAAMI chamber. As you probably know, data is scarce.

Sierra 6th edition lists the following:

300gr SMK 78.7gr Retumbo @ 2450fps with COAL 3.680”

*But*

I got this from Hodgdon’s via email:
300gr Elite Hunter, start load of 82.0 Retumbo @ 2439fps, max of 90.1 @ 2671 COAL 3.681”

Can anyone weigh in? Where is the real max load? They’re not even close! (Except for the load length)

 

[spife7980]

I’m looking for data to deconflict different sources for a max load. I’m using 300gr Berger OTM with Retumbo. Standard SAAMI chamber. As you probably know, data is scarce.

Sierra 6th edition lists the following:

300gr SMK 78.7gr Retumbo @ 2450fps with COAL 3.680”

*But*

I got this from Hodgdon’s via email:
300gr Elite Hunter, start load of 82.0 Retumbo @ 2439fps, max of 90.1 @ 2671 COAL 3.681”

Can anyone weigh in? Where is the real max load? They’re not even close! (Except for the load length)

It depends entirely on your own personal situation and parts.
See why the “start low and work up” disclaimer is on everything?

 

[Castloader]

Yes of course. I’m a seasoned reloader. But where is the real start? The max load in one book is lower than the start load in another. I will be working up, but with the cost of components, I’m trying to avoid unnecessary waste. Should I go with Hodgdon’s advice (They pointed to the Sierra manual with a different bullet), or the Berger advice(also a different bullet but the same manufacturer at least). I was hoping to connect with someone who uses Retumbo in this caliber.

 

[Dogtown]

For comparison purposes, here's what QL says about that combo

 

[Mareshow]

Any chance you can do one of those up with the same bullet and N570?

 

[Dogtown]

N570

RL33 while we're at it (better suited to an improved chamber though)

 

[ForgeValley]

Yes of course. I’m a seasoned reloader. But where is the real start? The max load in one book is lower than the start load in another. I will be working up, but with the cost of components, I’m trying to avoid unnecessary waste. Should I go with Hodgdon’s advice (They pointed to the Sierra manual with a different bullet), or the Berger advice(also a different bullet but the same manufacturer at least). I was hoping to connect with someone who uses Retumbo in this caliber.

Here is some info that was given to me. I'm working up a load with the 300 Bergers and Retumbo, I will probably start around 89.

 

[Moses42ak]

I have a couple loads that I tried, here’s the data:
300 SMK
CCI250
89.7 grains Retumbo
2741 FPS

 

[M77]

here you go , this is my data

 

[Castloader]

Thanks everyone, this is precisely what I was hoping for.

 

[Moses42ak]

Hit the range today and ran some RL33 behind the 300 SMK. Details and results below:
71-74*, 71-65% humidity.
338 Norma CIP chamber, CCI 250 primers.
Badger M2008 action with 26” Rock Creek barrel. Peterson Brass on 3rd firing. 5 rounds for each powder charge.

96 grains RL33 - 2,801 FPS, 25 FPS ES, No pressure signs

97 grains RL33 - 2827 FPS. The first round came out at 2,775 but the following 4 rounds were, in order, 2842, 2849, 2803 and 2870. Not sure what was going on with this charge.

98 grains RL33 - 2,885 FPS, 15 FPS ES. This one started showing some pressure signs with bright spots on the brass.

I’ll back it down to 95.5 - 96.5 and start tuning for accuracy.

 

[Mareshow]

Loaded 10 Rounds of the following

Rifle Specs:
Impact 787 magnum action
26" 1/9 T Krieger MTU barrel
Foundation Genesis 2 Stock
Heathen 5 port brake

338 Norma
300 gr Berger Hy OTM
Federal 215M primers
88.0 gr VV N570 Power
COAL: 3.717" This gives about 1/8" of gap in the front of an AICS LA mag

I did not Chronograph these yet but based on where I was hitting on the orange plate at 460M I'm at about 2750 FPS. I'll load more and see.

They grouped really well at 100 till I decided to screw up on shot number four (the high one). The one on the lower left was my sight in round

At 460m the 3 round group is just about 3.25 inches I would have shot more but I wanted to save the last round for 690m. Wind was direct cross at approx 5 mph

Will load more of these and Chronograph them to see a result. So far super impressed!

 

[Mareshow]

Back to the Range this time at 200 m
Conditions:
15C
6-9 mph diagonal wind from about 10:30
Sunny with heavy mirage

This load was:
300 gr Berger OTM
Fed 215m
88.5 gr VV N570
same COAL

I loaded some 88.0, 89.0 and 89.5 as well and they just didn't perform as well at 200m.

the 88.0 was about 3/4 MOA
89.0 was 7/8 MOA
89.5 was 1 MOA
Very happy with the results going to load more and do some official velocity numbers and see if I can dial it in more

Very easy to load for though compared to even 300 norma. doesnt seem to be as picky

Next I'm going to go up in 0.1 gr increments from 88.0 to 88.6 and see if there is anything there as well as load some more 88.5

 

[Mareshow]

88.5 gr of N570 Chronograph data. This includes cold bore and clean bore shots. But it appears to have settled out very nicely. I could push the speed a little bit more but I'm very happy with the accuracy results as well as the consistency. So I think I might stay put

 

[M77]

88.5 gr of N570 Chronograph data. This includes cold bore and clean bore shots. But it appears to have settled out very nicely. I could push the speed a little bit more but I'm very happy with the accuracy results as well as the consistency. So I think I might stay put

Realistically the happy place for the 300 OTM in the Norma is 2700-2735 , pressure becomes a problem pretty quick after that.

 

[Hathaway98]

Anybody running 250 Bergers? I’ve got imr 7828ssc which seems like it ought to fit this case pretty well, especially with the 250’s. Really wish Berger had about a 275gr pill….

 

[Thunderkok]

There is also data in this older thread

338 Norma Mag Load Data

It should be somewhere between 88, 6 and 90, 3, depending on whether I adjust only BA or BA and Z0. I'll look into it and post something, when I get the right load.

www.snipershide.com

 

[Swamplord]

Reloder 33 worked for me with 300 & 325 gr bullets

 

[Morgan Scott Johnson]

Here's a few. From the gentleman who sold me might 338 Norma. If this will help anyone.

 

[bbhank]

Satterlee Test on .338 Norma Rogue Improved

Peterson Brass
CCI250
Retumbo
Berger 300 Grain Otm

Started at 89.3 Grains and worked up to 96.5 in .3 increments. 96 on up was crunchy when I seated them but by the time I got to the range they had some room to shake the cartridge and hear powder moving. I didn't get any pressure so i ordered a drop tube for my 419 funnel hoping to squeeze in a little more powder.


Here's the target and the graph. 89.5 & 93.8 were not picked up by the chronograph!

 

[M77]

got a pic of the case? whats your COL

 

[bbhank]

got a pic of the case? whats your COL

.338 Norma on the right and my fire formed case on the left.

 

[CaseFinder]

Satterlee Test on .338 Norma Rogue Improved

Peterson Brass
CCI250
Retumbo
Berger 300 Grain Otm

Started at 89.3 Grains and worked up to 96.5 in .3 increments. 96 on up was crunchy when I seated them but by the time I got to the range they had some room to shake the cartridge and hear powder moving. I didn't get any pressure so i ordered a drop tube for my 419 funnel hoping to squeeze in a little more powder.


Here's the target and the graph. 89.5 & 93.8 were not picked up by the chronograph!
View attachment 8092277View attachment 8092278

The current .338 Norma reloading thread is broken and cannot be repaired. So Frank told me to start a new.

I am brand new to this and build a .338 Norma Rogue Improved and will be fire forming brass with Lapua Brass 87.5 grains of Retumbo and 250 Grain Berger 250 Grain OTM's

Stay tuned for more!!!

Curious, so you find any significant differences in performance in 338 Norma Rogue/AI versus 338 Lapua Rogue/AI? Assuming you use Whidden dies for reloading?

 

[bbhank]

Curious, so you find any significant differences in performance in 338 Norma Rogue/AI versus 338 Lapua Rogue/AI? Assuming you use Whidden dies for reloading?

I don't have any experience with any other magnums at this point, just this one. What I can tell you is this is very soft shooting rifle for a 300 grain berger moving at 2960FPS.

I am using whidden dies and John has been great to work with for sure

 

[CaseFinder]

I don't have any experience with any other magnums at this point, just this one. What I can tell you is this is very soft shooting rifle for a 300 grain berger moving at 2960FPS.

I am using whidden dies and John has been great to work with for sure

With Norma factory ammo I have yet to try, I am finding it strangely hard to come by, which, unless I am mistaken, the military uses as much as they do...