Home Forums Reloading Big Game Rifles Forming .350 Remington Magnum cases

I never have had anything to do with the .350 Remington Magnum before, but I now find myself with two of them. One is a dandy stainless/synthetic Ruger 77 that I will sell because it is right handed and I am not; the second is a left handed one on a Remington 700 action. I had a buyer close to pulling the trigger on the Ruger, but he got understandably anxious about the availability of brass. Based on gunbroker auction prices, the stuff has become quite scarce with exorbitant prices. Fortunately it can readily be made from other belted magnum cases. Here are the steps I went through to make the brass.



I started with .264 Win brass, which I had in abundance. 7mm Rem Mag or .338 Win Mag would work just as well. Longer magnums like the .300 Win Mag would also work as well, but you would be moving more metal.

I used a .44 mag carbide sizing die to push the shoulder back. I experimented with following that up with a .40 S&W carbide sizer, but that proved unnecessary. I made a depth gauge from aluminum pipe that fit around the case and was sandwiched between the ram of the loading press and the frame to control the location of the shoulder. Before I made the gauge it was easy to push the shoulder back too far.

Next I trimmed the cases in my trusty old Sheldon lathe to slightly over final trim length. By carefully indexing the belt at the front of the chuck, and not moving the carriage between cases, I could control length surprising consistently.



Full length size with Imperial die wax (which is God's gift to reloaders, if you have not used it.).

Trim to final length (needed to take off about .02" to get things cleaned up.)

Neck turn using the lathe again. The loaded cases had a neck diameter of .391"; SAAMI dimension on the chamber is .388", so quite unsurprisingly loaded rounds would not chamber. I turned the necks to .384" and they chambered fine. If this was benchrest reloading, I probably would have gone something more like .386" in order to promote accuracy.

I know they make a form and trim die for this round, but they run about $50 and I do not think it would have been much--if any--faster, once I got my technique figured out. Now I have cases that I can sell with the Ruger as well as use on my own. I'd like to think that old time loaders like Ken Howell and Ken Waters are smiling down on my modest efforts at case forming.

If you are unfamiliar with the .350 Remington Magnum, Remington introduced it in 1965, along with the 6.5 Rem Mag and the Model 600 rifles for which they were designed. Think of it as a short .35 Whelen--200 gr bullets at 2600 fps and 250s at 2400. I enjoy having that much punch in my hands when hunting in grizzly country in Montana.

Thanks for sharing. It is amazing the things we can do with tools for which they were never intended.

I am not entirely sure that is a compliment.

It is absolutely a compliment. I am always impressed by ingenuity and industriousness.

I suspect it is somewhere above average in terms of technical difficulty but not hugely. I could have done it without the lathe, but when you are doing 100 cases it sure speeds things up. I still just have a hand crank trimmer, so that was the most tedious task.

Reloading used to involve more "Rube Goldberg" approaches than it does today because it was born out of shortages and lack of sophisticated tooling. Think about the old Lee hand dies and the powder scoops.

But I grew up in rural Montana, so some residual ranch kid problem solving still persists.

I also posted this thread because I thought maybe somebody with more advanced skills (particularly in machining) could offer improvements to my technique.

Shades of George Nonte.

Just found this in a Google search. I run 300 win mag brass through the 350 rem mag die with the decapping assembly removed. Then take the handle off my rcbs case trimmer and chuck the drill on the shaft to trim. Next I put the rcbs neck turning fixture on the trimmer and run that through all of them. Somewhat complicated compared to anything else I do but at over $2/ casing I can spend a little time on them and still be ahead. Are you annealing?

I too have a couple of 350 Mag rifles. After buying the first one I formed brass from 7mm RM and 338 WM. I used a different method. If I recall, I took a seating die with the seating stem removed, ran the case into the die (I agree on the wax lube). Then I cut the case with a hack saw to some over final length. ran the case into a sizing die. Trimmed the cases in my Forester trim tool (with a battery operated drill in place of the handle). Then, if needed, I ran through the sizing die again. I cannot remember if I had to deal with neck thickness or not, but I don't think so.

As far as brass, I attend gun shows quite frequently and have bought 350 Mag brass very cheaply. I now have a life time supply. On a recent show there was loaded ammo for sale for less than new brass price, but I already had enough.

I just bought 350 Rem Mag cases from Hornady. Be Well, Rustyzipper.

Where'd you find that?!!!

350 Remington Mag or 350 Legend?

I don't remember where, just that I got them. I also bought an M600 in Rem Mag from an individual for the ammo and brass that came with. Be Well, Rustyzipper.