So the other day I told you about the Mansion at Werribee Park, phase two of our road trip down south; but what of phase one? What was that all about? Well phase one was really the mission of our road trip in the first place! Not so long ago you may have read in Return to Nitro Express that I had just received from my good friends at The Stockade my new express rifle, the poorer second cousin to the double rifle I’m hoping to get my hands on one day…
That rifle is my Ruger No.1-H Tropical Single-Shot rifle chambered for the safari classic – the .450/400 3” Nitro Express. Now I will tell you a bit more about my No.1 in a few days, but for now, we need to get back to the purpose of our journey - brass. My girls and I were off to sunny Seymour to hang out with Bruce Bertram of Bertram Bullet Company, talk hunting, check out the factory, have a few beers and pick up a batch of brass to start load development for the 450/400.
Bruce welcomed us after our 750 kilometre drive from Sydney, a remarkably enjoyable trip given that we had our two and four-year-old daughters in the back. They went racing off into the grass while Bruce showed us around and we unpacked our gear. We gathered the team and headed off to the factory.
I felt like a kid in a candy store!
Rows and rows of traditional punching machines, dedicated turning stations and modified and purpose built machines filled the factory and my nose was filled with the fragrance of metal and oil and cutting fluid. A few curls of brass swarf lay on the table by the head and neck turner and in big drums ready for recycling. Dave - Bruce’s son - was busy setting up the neck and shoulder forming operation for a .338 monstrosity that makes the Lapua Magnum look like a pussycat – this batch was for an American wildcatter with dreams of making it big in the annals of cartridge development history.
It was after hours, late on an autumn afternoon. The troops had gone home for the day and the guys were hanging around to show us how it all happened. Bruce and Dave took us on a tour of the plant and tag-teamed in explaining the case forming process to my wife and I. We gave the girls a bucket each and they spent their time collecting off cuts from the neck turner. We need one of these at home…
So the case forming process; I could see I was going to have a lot of fun here. While my career has taken me to a number of manufacturing facilities with similar process to making aluminium soft drink and aerosol cans, make brass cartridges is something else! And the result feeds my passion, literally!
When we visited, the factory was set up to run brass for the .338 Lapua Magnum. Here’s a photo I took of a series of “cartridges” in the various stages of the case forming operation. I’ll follow with the details of what’s going on…
- The brass cup arrives at the factory already annealed after the initial forming from a billet of brass;
- First draw – the cup goes through a drawing operation to beginning the forming process. From here the brass is loaded into a basket and will spend some time in the anneal furnace; the time will vary depending on the total weight of brass in the basket;
- Second draw – again, the brass is drawn and sent for another visit to the anneal furnace;
- Third draw – yet another drawing operation and again a visit to the anneal furnace;
- Fourth draw – this is the final draw and the brass case at this stage of the processing is at its maximum length. There is no anneal after the fourth draw;
- Trim to length – the case is trimmed to length ready for the forming operations that will start to really bring out the metallic cartridge we are all familiar with;
- Heading – a punch tool is made for the heading operation. In this step, a rim is formed with a significant flange on the case as is the primer pocket. All cases are formed with the flange at this stage regardless of the final cartridge design as the flange is necessary for locating the brass case when the flash hole is pierced. Also in this same operation we see the the headstamp punched denoting the cartridge name and any other detail required for that particular case. The rim, primer pocket and headstamp are all formed with the one tool in one single operation. The case is now dropped into a table that holds the case in place while the flash hole is pierced; the flange stops the case from falling through the table . Then they neck anneal using a gas flame;
- Neck and shoulder forming is a full length size operation. The cartridge body is now correct to specification;
- Head and mouth turn – each brass case has the flange machined off to form the cartridge rim to specification. The mouth turning at the same time will trim the case to length. A final neck anneal at this stage in a gas flame and the job is done.
Quite a job! I’ve been using Bertram's brass since 2008 and it is handling my handloads very well – many of which are full power loads out of my .450 Ackley Magnum. I’ve not junked any cases and the only ones I’ve set aside are the two I kept for sentimental value that I used to drop my Cape Buffalo in Zimbabwe a few years ago.
There’s more to come from Bruce so stay tuned.