Peterson 300 Norma Mag brass

[Swamplord]

First look (for me) at the 300 Norma Magnum brass made by Peterson ...

This stuff is pretty darned good, probably some of the best brass I've seen yet, in regards to variation in measurements on factory new unfired brass, pretty consistent in length and weight in the 100 pcs I received ,

Length was right at 2.484" for 90 pcs, 8 pcs at 2.483" and a couple at 2.481"

Case h20 capacity was measured with fired WLRM primers seated in 20 cases randomly selected from the two 50 pc boxes ,
16 cases at 103.6 gr h20
2 at 103.5 gr and 2 at 103.4
I stopped there as I was satisfied with the consistent h20 weights I was getting

rim diameters all came in right at .584" , web diameters above extractor groove were at .580.5" and top of body at the shoulder junction at .561"
neck thickness was .016" from about 30 cases I measured picked randomly from the 100 pcs,

all the shooters that intend to use this brass for improved wildcats may want to make certain your chamber reamer dimensions are addressed properly at the .200" height from the base of the casehead , make sure you don't end up with .589-.590" on the reamer at that location
custom dies should be made accordingly for a properly sized case

it is crucial for longevity of the web and primer pockets ........ to tighten up that area if you intend on using the Peterson 300 Norma Mag brass, I measured new unfired 20 pcs of Norma made 300 NM, 20 pcs of 338 NM brass and 20 pcs of Lapua made 423 Dakota brass and confirmed that they all had .583" diameters at the web right above the extractor groove, may not seem like a lot of difference but it will matter with max pressure loads,

case weight was sorted by lightest to heaviest in rows as shown in pic, from left to right

1st row 307.6 gr
2nd 307.8 gr

3rd 308.1 gr
4th 308.3 gr
5th 308.4 gr

6th row 309.1 gr
7th 309.4 gr
8th 309.5 gr

9th 309.7 gr
10th 309.8 gr
11th 309.9 gr
12th 310.0 gr

the last two on the right came in at 311.2 gr and 311.6 gr , upon inspection I found that the flasholes were not deburred inside the case like all the others were, must have been missed in the factory, no matter I can clean up the flasholes or make them into modified case for my 6.5 Skuldryl and 408 Skuldryl wildcats

Once I have all the cases fireformed, neck turned, case mouths deburred and trimmmed to one length I believe the weight runout will be reduced considerably as I have noticed some burrs on the insides of case mouths on some cases and none on others

By the end of my 4 hour case inspection I was pretty satisfied with the results and immediately went to Graf's and ordered a bunch more while it's still in stock, I suggest you do the same or you will miss the first production run of this awesome brass, no telling how long it may be until it's available again

 

[wolffman]

View attachment 98341 View attachment 98342 View attachment 98343 View attachment 98344 View attachment 98345 View attachment 98340 First look (for me) at the 300 Norma Magnum brass made by Peterson ...

This stuff is pretty darned good, probably some of the best brass I've seen yet, in regards to variation in measurements on factory new unfired brass, pretty consistent in length and weight in the 100 pcs I received ,

Length was right at 2.484" for 90 pcs, 8 pcs at 2.483" and a couple at 2.481"

Case h20 capacity was measured with fired WLRM primers seated in 20 cases randomly selected from the two 50 pc boxes ,
16 cases at 103.6 gr h20
2 at 103.5 gr and 2 at 103.4
I stopped there as I was satisfied with the consistent h20 weights I was getting

rim diameters all came in right at .584" , web diameters above extractor groove were at .580.5" and top of body at the shoulder junction at .561"
neck thickness was .016" from about 30 cases I measured picked randomly from the 100 pcs,

all the shooters that intend to use this brass for improved wildcats may want to make certain your chamber reamer dimensions are addressed properly at the .200" height from the base of the casehead , make sure you don't end up with .589-.590" on the reamer at that location
custom dies should be made accordingly for a properly sized case

it is crucial for longevity of the web and primer pockets ........ to tighten up that area if you intend on using the Peterson 300 Norma Mag brass, I measured new unfired 20 pcs of Norma made 300 NM, 20 pcs of 338 NM brass and 20 pcs of Lapua made 423 Dakota brass and confirmed that they all had .583" diameters at the web right above the extractor groove, may not seem like a lot of difference but it will matter with max pressure loads,

case weight was sorted by lightest to heaviest in rows as shown in pic, from left to right

1st row 307.6 gr
2nd 307.8 gr

3rd 308.1 gr
4th 308.3 gr
5th 308.4 gr

6th row 309.1 gr
7th 309.4 gr
8th 309.5 gr

9th 309.7 gr
10th 309.8 gr
11th 309.9 gr
12th 310.0 gr

the last two on the right came in at 311.2 gr and 311.6 gr , upon inspection I found that the flasholes were not deburred inside the case like all the others were, must have been missed in the factory, no matter I can clean up the flasholes or make them into modified case for my 6.5 Skuldryl and 408 Skuldryl wildcats

Once I have all the cases fireformed, neck turned, case mouths deburred and trimmmed to one length I believe the weight runout will be reduced considerably as I have noticed some burrs on the insides of case mouths on some cases and none on others

By the end of my 4 hour case inspection I was pretty satisfied with the results and immediately went to Graf's and ordered a bunch more while it's still in stock, I suggest you do the same or you will miss the first production run of this awesome brass, no telling how long it may be until it's available again

Just ordered 50 to try out. Have both Norma and lapua 423 Dakota brass to compare it to.

 

[Swamplord]

I ran 20 pcs through a 338" expander then a .358" expander and then through a 338 Norma Mag full length die adjusted to set false shoulder to headspace in my 338 PRO chamber, 20 gr of Blue Dot topped with cream of wheat and capped with paraffin wax, gonna pop them tonight

 

[Swamplord]

Quick update on my last post.....

Had a very busy Memorial Day weekend messing around with the new 300 Norma Magnum brass from Peterson ....

150 pcs of brass Mom banged (Malt O Meal and Blue Dot) into several of my wildcats based off the 300 Norma Mag parent case ....

338 Precision Rifled Ordnance (in pics)
6.5 Skuldryl
300 Long Range Hunter
8mm Long Range Hunter
375 Long Range Hunter

Also have brass necked down for the 7mm Long Range Hunter and necked up for the new 400 Skuldryl (408 cal) wildcats ....

Some time ago I heard a rumour that Peterson brass was difficult to fireform into an improved wildcat version of the parent, not sure what those individuals experienced or what their process was in fireforming Peterson brass was but my results were 100 % satisfactory, have not lost a single piece of brass and every pc of brass formed out beautifully, top of body/shoulder junction is a bit rounded as usual with other brass but case dimensions were spot on and headspace for new chamber was set correctly ....

Next up is powder selection and load data workup , stick around for more info coming in the weeks ahead ....

Pro Martusheff aka Swamplord

 

[Swamplord]

The one 6.5 to rule them all !

Testing the necked down 300 Norma Mag brass with uncoated 150 gr SMK's, velocity at 3550 fps and no signs of pressure yet , had 25 pcs of brass fireformed to work with and the shooting will commence with the once fired brass now that I have load data established

Did not shoot for accuracy at this point, just fireformed brass and searching for pressure, haven't found it yet ....

Hoping to see that new 6.5mm Berger bullet soon, Ima ready for it !

 

[Swamplord]

The 300 NM Peterson brass was fairly easy to neck down then MOM banged in chamber with 17 gr of Blue Dot pistol powder capped with paraffin wax and lit with WLR primers,

the 6.5 Skuldryl was designed to simplify the forming process over the 6.5 Prometheus which required multiple steps in brass prep, even a wildcat inexperienced guy can get a simple 300 Norma Mag bushing die and standard bushings for .308" .284", .277" and .264" to make a bunch of these in a single evening

 

[can1010]

in real world what is the velocity and barrel life differences in the 2 6.5s does the longer neck of the pro have any advantages? we have all heard the talking points just wondering if you noticed any

 

[Swamplord]

Necks longer than bullet caliber of cartridge have absolutely zero effect in improving "barrel life" or aiding accuracy , it's a selling point to generate interest in an uninteresting cartridge, hype and nothing more

longer necks have more negative impact on pressures and accuracy over a similarly designed cartridge with a shorter neck

I've tested multiple caliber designs of wildcats off the 300 & 338 Norma Mag parent cases and concluded that a neck longer than caliber of cartridge is useless ...... in fact as bullet diameter goes up you are better off with shorter than caliber neck lengths, for example in my experience in 375 cal., a .350" length neck is better than a full .375" long neck, that extra case length is better suited for case capacity than addional tension and drag on the bullet before release



.....opinions will differ but watch for the salesmen, everybody will hype up their new whiz bang for a buck, my only interest is pure max performance possible from a case and nothing more, no magic case design tricks to double "barrel life" ... whatever the hell that is

 

[Wind Gypsy]

I and others have struggled with sticky extraction that I think stems from norma brass expanding at the web. Going off memory here but I believe my cases are .5835 after firing and that is not changed by the whidden or forster 300 NM dies I have.

Is there any reason to believe the Peterson Brass will be more stout here or does it need to be addressed with custom dies that size the web?

 

[Swamplord]

get a 300 NM full length sizer die, cut the top and bottom of die off to create a small base size die to keep the web from growing with each firing, a bit of experimenting and you will find the proper locations to cut the die at

 

[FEENIX]

Man, I think you have the coolest wildcats and the name to go with it.

 

[jonthomps]

Bought 200pcs of Peterson 300NM brass for a new build. Have ran 75 rounds through it so far. Great brass! MUCH tougher than Norma brand brass. I'm already at 2930fps with a 230gr Berger and a new barrel with no pressure signs. Way to go Peterson!

 

[sp6x6]

So you see this as a upgrade from the Norma? I have 2-338NM and could use a bit more brass.On sites for sale they say to start with a more reduced load as thicker brass,do you find this true.

 

[Rhovee]

I have some 300 norma mag Lapua brass I can give you some measurements if your interested?