What is the best way to make 338 Whisper Brass?

[yote_slayer31]

I have been searching for the best method to make 338 Whisper brass. I will be using either the 6BR brass and necking up or 308 and trimming and forming. I understand the easy way is to use 7BR brass and expanding it. However I can't find quality 7BR brass. I like the idea of using 308 Win Palma brass from Lapua, then neck turning it for the most uniformity after I trim and form it. I don't want to have thin case necks from necking up 6BR brass.
Any input would be great. Also, what do I need in terms of dies or tools to make each? Thanks

 

[yote_slayer31]

Re: What is the best way to make 338 Whisper Brass?

Does anyone shoot a 338 Whisper? Where do you get your brass?

 

[yote_slayer31]

Re: What is the best way to make 338 Whisper Brass?

BTT

 

[armorpl8chikn]

Re: What is the best way to make 338 Whisper Brass?

I do not have nor form for the 338 whisper but I can give you some advice about case forming.
I have made many 300Whisper brass from 223 as opposed to the 221 fireball. I know these 2 Whispers are different parent cases but it is the same concept. It may take a few more steps and tools but in the end I think you will have a better product if you use 308 brass. You may,and likely will, find that you need to ream and turn brass made from the 308 so kepp that in mind. If you have the equipment or have the means for the quality equipment then by all means use 308 brass. If you only need a couple hundred brass and live on a budget then get some 7BR brass, it isn't all that bad.

 

[yote_slayer31]

Re: What is the best way to make 338 Whisper Brass?

Thanks Armor. I still have a couple months until my barrel and stock show up. I guess I should start investing in the equipment and .308 Brass now so it doesn't hurt so much as a single large order.

 

[former naval person]

Re: What is the best way to make 338 Whisper Brass?

Ask Mag-Na-Port. They designed the cartridge.

 

[Adam B]

Re: What is the best way to make 338 Whisper Brass?

actually JD Jones designed the cartridge

 

[former naval person]

Re: What is the best way to make 338 Whisper Brass?

Yes...JDJ did that...but he died recently, so going to his company would be as direct as you can get...unless Madame LaFarge is around to connect.

 

[yote_slayer31]

Re: What is the best way to make 338 Whisper Brass?

My understanding of the 338 Whisper Number 1 I am building(there is a 338 Whisper Number 2 with a different parent case) is that it is the same as a 6mm Br just necked up to .338. I was hoping someone on here had some words of wisdom about the cartridge, performance, accuracy, and so on.

 

[Adam B]

Re: What is the best way to make 338 Whisper Brass?

Larry kelly, who owns magna port, recently died but I am pretty sure JDJ is still alive, at least I hope so, I was looking forward to seeing him this summer at the TC collectors meeting

 

[Ranb]

Re: What is the best way to make 338 Whisper Brass?

I shoot a 338 whisper using necked up 7mm br brass. I think I can get better results with formed brass and a slightly thicker neck.

I am trying to form brass using cut down 308 brass, but not getting good results. I have to take out the expander when forming the brass initially. I can use the expander after forming as long as I do not size the neck just prior pulling the expander back through.

The problem is that the neck near the shoulder springs back after forming by about ten thousand and is not uniform from piece to piece. This means that if I inside or outside turn the necks, then I will not get uniform results and the bottom of the neck will always be thinner than the top if I outside turn and thicker if I inside turn.

I will try anealing the top half of the brass prior to forming to see if this helps eliminate spring back while forming the brass.

Ranb

 

[Ranb]

Re: What is the best way to make 338 Whisper Brass?

So far so good. I figured that the brass was not springing back so much and the bottom of the uncut neck was a bit wider due to the gradually thickening brass of the brass body. The 7mm BR brass has about a .007" neck wall and my turned brass is about .009 to chamber in the SSK barrel. I annealed (lead dip) after turning.

I have yet to see how it shoots. I will be trying bullseye powder with the jacketed loads and will stick with WC820 for the cast.

1. 30-06
2. Cut down 1.480"
3. Sized with expander removed
4. Expanded
5. Neck turned from .020" to .009" and loaded with 305 grain cast from NEI mold
6. Some brass wrinkles when sized down
7. Some brass splits when expanding

Ranb

 

[Ranb]

Re: What is the best way to make 338 Whisper Brass?

I tried the new brass today, they worked ok. The NM04 (like bullseye) did not give me the low stdev I was expecting. I needed 1050 fps, but the stdev did not get below 40 fps unless I was up to 1100 fps. On the upside the 1100 fps load did give me a 1.25" five round group at 100 yards.

One of the reasons I wanted to make my own brass from 30-06 was that I felt the 7mm BR brass had a thin neck (.007") when opened up. But I was only able to make the new ones with a .009" neck. I did notice that most of the fired brass still had enough tension to not allow a 338 bullet to be pushed in by hand. Does this mean I should make the necks a bit thinner?

Ranb

 

[rleonard]

I spoke with Mr Jones a month ago (April 2013) He sounded very much alive!

SSK just put together a AR10 in 338 Whisper for me. I do not have it yet. Looking forward to a visit to pick it up. Looking and learning about ammo. Thanks for the great info.

Bob

 

[Ranb]

I am trying to form 338 whisper from 7.62x39 brass for my Savage bolt gun.


The 7.62 brass is about .020" longer than the 7mm BR brass. It shortens when fired though. It takes a hotter supersonic load to properly fireform. Repeated loadings with subsonic charges will not completely shape the brass. I am still waiting on a PPC bolt head to extract properly.

Ranb