Ballistics by the inch

.460 Rowland case wall thickness.

A friend dropped me a note, after looking over my previous experiments with putting .460 Rowland load power into .45 ACP cases, and asked a fairly simple question: Do you think that the case walls are actually thicker in the .460 Rowland?

Now, I have read several articles over the years which mentioned that the .460 Rowland cases were “stronger” with others saying that the cases were “thicker”. In fact, in the blog post cited above, I myself said:

Even shooting them in a gun designed to handle .460 Rowland power was risky, since the .45 ACP cases do not have the same strength as the .460 Rowland cases.

But is that actually true?

Good question. My Lyman 49th Edition Reloading Handbook doesn’t give case wall thickness for the .45ACP, and doesn’t list .460 Rowland at all. A quick check online also didn’t turn up any case wall thickness specs for either cartridge. As noted above, there are some gun writers out there who claim that the .460 Rowland case has thicker walls “for strength” but this claim isn’t made on the 460Rowland.com site that I could find.

So, being the data-curious guy that I am, I decided to just take some measurements and see what I found.

The only .460 cases I have are all Starline brass (I ordered 500 from them, and supplemented with other brass from factory Buffalo Bore ammunition – again, all of it marked as Starline), and I went through and checked a bunch with my simple calipers. Now, those calipers aren’t the pincer type, just the standard parallel-jaws type, so I only trust the measurements to about halfway down the case. And they all fell into a range of wall thickness from 0.0012″ to 0.0014″.

Doing the same measurement with ten different ‘marked’ sets of .45 ACP brass I also have readily to hand, the results were almost identical, with the vast majority of cases being 0.0012″ or a thousandth of an inch on either side of that. It didn’t matter whether the cases were nickle-plated or marked “+P”. The ‘marked’ brass was as follows:

  • Cor Bon +P
  • ELD
  • Federal Brass
  • Federal Nickle
  • R-P
  • S&B
  • Speer Brass
  • Speer Nickle
  • Starline
  • Winchester

And when you stop to think about it, there would be no reason or way for the case walls to be significantly thicker in the .460 Rowland cartridge, and still allow you to use standard .45 ACP reloading components and dies. If the case walls were substantially thicker, then you’d have to have slightly smaller bullets, if nothing else, and would probably need a different resizing die and/or neck expanding die.

Also, when I was conducting those experiments last summer, I didn’t note any differences in how the .45 ACP cases looked or functioned (when being reloaded) after being shot with .460 Rowland power loads.

My conclusion? That the .460 Rowland cases are no thicker walled than .45 ACP cases. They may still be “stronger”, if there is some metallurgical difference, but I doubt it. The real difference is in whether or not the chamber of the gun in which the ammo is being used is strong enough to handle the much-greater pressure of the .460 Rowland loads. Because remember, the maximum pressure for standard .45 ACP is just 21,000 PSI, and 23,000 PSI for .45 ACP +P — while the .460 Rowland cartridge reaches pressures of 40,000 PSI.

Of course, there are additional factors to consider (like recoil and timing) with the .460 Rowland cartridge, so you can’t just make the chamber of the gun stronger and then start putting those kinds of loads into .45 ACP cases. And you really wouldn’t want to accidentally put such power into a ‘normal’ .45 ACP gun — that could lead to catastrophic failure of the gun, and result in serious injury or death. So it still makes ALL KINDS OF SENSE to only load the longer .460 Rowland cases with that much power.

 

Jim Downey

March 22, 2014 Posted by | .45 ACP, .460 Rowland, Anecdotes, Data, Discussion. | , , , , , , , , , , , | 2 Comments

It’s like flinging thunderbolts.

You may remember that I have a small bit of an obsession with the .460 Rowland cartridge.  Ever since we tested it for BBTI, I’ve wanted one. As I noted in one of those articles:

I said it before and I’ll repeat it here: if you carry a .45, you should instead be carrying a .460 Rowland.

 

So, early this year I put in an order for a .460 Rowland conversion kit for a new Gen 4 Glock 21.

I’m planning on doing a full formal review of the kit and the resultant gun, but I thought I’d share some of my experience so far. Why “so far”? Well, because I haven’t worked out all the minor kinks yet.

OK, first thing: it didn’t just take the 3 weeks for delivery which was promised. It wasn’t even 3 months. It was almost six months. And a buddy of mine who ordered his before I ordered mine still hasn’t gotten his. So, there’s that.

Second, and part of the reason for the delay, I didn’t receive a new barrel which was marked .460 Rowland. Rather, I got what looked like a standard Wolff .45 barrel. But it had indeed been rechambered to handle the .460 Rowland cartridge. Before I received the kit I got an email advising me of this problem, and I figured I could just roll with it. This is what I got in the kit:

.460 Rowland Conversion Kit.

.460 Rowland Conversion Kit.

 

Going clockwise from the top: That’s the threaded barrel, a screw-on compensator, spring assembly adapter, small serving of red loc-tite, and the heavy spring assembly (which is actually the Gen 3 design, but with the adapter works just fine in my Gen 4).

As advertised by .460 Rowland, the conversion takes like 30 seconds. If you can field strip your Glock, you can do the conversion. I’ve opted for using blue loc-tite rather than red, since it still works well but allows me to remove the compensator easily if I need to.

How does it work? Well, I’ve taken it out to the range several times now, shooting both factory rounds as well as my own reloads. Doing some informal chrono tests, I have gotten exactly the kind of performance promised and expected. The Buffalo Bore 230gr JHP were right at 1300 fps. 200gr RNFP reloads were at 1380 fps, and 185gr XTP (JHP) reloads were at 1410 fps. And those reloads are actually fairly mild — just 12.5gr of Longshot powder — based on what data I’ve seen, I could probably push that to 13.5gr without any risk. (Don’t consider this an endorsement — do your own research, and work up your own loads using published data and standard safety practices.)

Shooting the .460 loads out of the Glock is like shooting a .44 magnum (which I have a fair amount of practice with), but having 13 rounds on tap. Seriously, it’s like flinging thunderbolts with each shot. And the recoil is surprisingly manageable, though I’m not someone who is very recoil shy.

So, why did I say I was still working out the kinks?

Well, there’s a problem with the magazines. Here’s what happened after the first outing:

Glock 21 magazine

Glock 21 magazine

 

Look closely on the left side of that magazine, and you’ll see that there’s a tab which has been torn a bit loose and pushed forward. That’s from the force of the .460 cartridges slamming forward. At about this point the magazine would no longer release or insert smoothly. That was after my first outing, with about 60 .460 Rowland shots fired. And actually, I damaged two magazines to that extent with those 60 rounds.

So after that first outing, I took a Dremel tool to the magazines and cut away about 1/8″ of material, and flattened the whole face back into position. Today I took those two magazines back out to the range, and ran about another 50 rounds through the gun using the two of them. Here’s one of them after today’s outing, next to a new unaltered magazine:

Two Glock 21 magazines.

Two Glock 21 magazines.

 

More problems. This time, the little metal tab snapped off, as well as distorting the face of magazine again. Clearly, I need to sort out how to fix this.

Two other things I want to mention. One, I tried shooting standard .45ACP cartridges out of the .460 Rowland conversion. They work wonderfully. Seriously, there’s almost no recoil, the gun cycles just fine (with my mild reloads as well as factory +P self defense ammo), and there’s no accuracy loss that I could determine casually shooting the gun. So, that’s a plus.

But the other thing? Heh — take a look at what happened with my front site today:

Glock 21

Glock 21

Yeah, it really shouldn’t be facing that way, nor sticking up quite so much. But I can fix that easily enough.

If you have thoughts on how I can correct the magazine problem, I’d love to hear ‘em.

 

Jim Downey

September 23, 2013 Posted by | .45 ACP, .460 Rowland, Anecdotes, Discussion. | , , , , , , , , , , , , , , , , | 7 Comments

Just take a little off the sides, leave the top alone.

So, yesterday was our best day ever for this blog, doing 50% more traffic than any previous day. Why? Well, thanks to a link from The Firearm Blog about my experiments to alter the Buffalo Bore 340gr .44mag loads I’ve written about recently. So I wanted to say thanks to Steve over there, and to all his readers.

And I also wanted to report how the rounds behaved after a trip to the range this morning. I think pictures tell the story just fine. Here’s the first one:

20130829_105140

That’s a 3″ circle, just for reference. Those are three shots, fired from a sitting position at 50 yards (well, paces, so something pretty close to 50 yards). That’s with the standard, unaltered, 340gr rounds from my Winchester 94AE which has the standard iron sights. I wasn’t trying for super accuracy, just the sort of quick sight and shoot you’d do when hunting at that range. It may be worth noting that I had to hand-feed each round into the chamber of the gun, since these unaltered cartridges will not feed from the tube magazine. If you look close, you’ll see that I marked through each hole with a blue Sharpie.

Here’s the second picture:

20130829_105528

Exact same parameters as the first pic, but this time with three rounds which had been shaved as discussed in the previous posts. And since these rounds will reliably feed from the tube magazine, they were shot then the gun was cycled and then the next shot taken in fairly quick sequence. For clarity, I marked through the second set with a red Sharpie.

My conclusion? They’re as accurate as the unaltered cartridges. Which is to say, within the limits of my ability using them like that. With a good shooting rest and a scope you might be able to tell a difference, particularly at greater range. But for what I wanted them for, they’re entirely suitable. YMMV.

 

Jim Downey

August 29, 2013 Posted by | .44 Magnum, Anecdotes, Data, Discussion., Links | , , , , , , , , , , , , | Leave a comment

You want me to stick it *where*??

The beginning of this month, I posted an entry about my initial experiment altering one of those heavy Buffalo Bore 340gr +P+ rounds for .44 magnum. I intended to revisit that experiment in short order, and then write up further thoughts on the matter.

But then my month got rather unexpectedly complicated, with my wife needing an emergency appendectomy, a lengthy hospital stay, and then a fair amount of additional care and treatment. She’s doing grand now, but most of the past month was a bit of a blur.

So I’m just now getting back to the experiment. Fortunately, someone over on Facebook made a suggestion which proved to be just about perfect:  use a pencil sharpener. Specifically, one designed for the larger style of carpenter’s pencils.

The first one I found here at home didn’t work. But my wife remembered an older (and cheaper) one she had and dug it out for me. I gave it a try, and here’s the result:

20130824_140346

The cartridge on the left is the one I initially altered using a rasp and then sandpaper. The one on the right is the one I used the pencil sharpener on. The sharpener itself is there — just one of those cheap plastic ones for schoolkids. If you look close you can see that the blades in it have a bit of rust on them. And the pile of shavings is what I took off the right cartridge.

It took just a little playing around to figure out the best way to shave off the shoulders on the bullet, and just how much I needed to take off, but soon I got the hang of it. Here’s a pic with that initial one, one unaltered cartridge, and three finished cartridges:

20130824_143208

I’ve since done a full box of cartridges. When you get the hang of it, it only takes a couple minutes each. And the results are *very* satisfactory. They’re consistent. Smooth. Uniform. And I have carefully measured the shavings from each cartridge, and they all fall between 8 and 10 grains of lead removed.  Most importantly, they all feed perfectly reliably in my Winchester 94 lever-action.

So if you’ve encountered this problem, you might want to give this a try. You may need to experiment with a couple different sharpeners, and it’s possible that a different design one would work better for you (either an electric one or one that grinds off material rather than cutting it directly). But it’s worth a shot.

Jim Downey

August 24, 2013 Posted by | .44 Magnum, Anecdotes, Discussion. | , , | 9 Comments

There’s more than one way to skin a cartridge.

So, the beginning of July I posted an entry about some informal .44 data I had collected.  As I said at the time:

I was prompted to do so because I had picked up some new Buffalo Bore ammunition that I wanted to try.

Specifically, this ammo:  Buffalo Bore 340gr .44mag

Heavy .44 Magnum +P+ Pistol and Handgun Ammo

And I was VERY impressed with the performance of that ammunition, since it generated over 1653 fps/2063 ft-lbs out of my Winchester 94.  However, there was a problem: it wouldn’t feed in my levergun. Oh, it shot and extracted just fine, but you couldn’t rack a new cartridge from the magazine into the chamber — they would invariably get stuck. Thus making the gun a single-shot, at least as far as that particular ammo was concerned.

So I started thinking about ways around this problem.

My first thought was that perhaps I could develop a similar cartridge using a .44special case. I knew the history of the development of the .44magnum, so i figured that it was probable that the .44special brass would withstand the pressures involved, and give me about 1/8th inch (the difference between the case length of the .44special and the .44magnum) to play with. I found a suitable bullet, and did a little research to see whether anyone had recently tried to develop such power out of a .44special case.

My research pointed to the possibility of developing full .44magnum power out of a .44special case (which was what was done historically, so no big surprise there). And over the course of the last month I worked up two different flights of test ammo experimenting with that idea.

What results did I get? Well, let’s just say that you can indeed get some very powerful rounds using .44special cases. Indeed, using 240 grain bullets (which are fairly standard for the .44) I had considerable success. The rest of the equation is left to the experienced reloader to determine for themselves.

With the 330 grain bullets, though, it was a different story. When approaching the upper end of the published  data for .44magnum, I started to see indications of stress on the spent brass which made me … nervous. Enough so that I decided not to risk shooting the last couple of test rounds. Draw your own conclusions.

And the chronographed power results were only about half of what the Buffalo Bore ammunition I was trying to emulate demonstrated.  Hmm.

Now, it is possible that with a different type of gunpowder, I might be able to come to a different result with my shorter .44special reloads. Maybe.

But we all know how hard it can be to find preferred types of gunpowder these days. So I decided to reconsider my strategy. After all, what I wanted was to have the power of the Buffalo Bore loads, but in a cartridge which would feed reliably in my levergun.

The result? I decided to try to change the shape of the bullet in the Buffalo Bore cartridge, so that the hard leading shoulder would be rounded off in such a way as to properly feed in my gun. After a bit of experimentation this afternoon, this is what I came up with:

20130801_171004

Note the rounded cartridge on the left, next to an unaltered cartridge on the right. In the pan for my balance beam scale you can see the bulk of the lead removed from the bullet in the cartridge on the left. Now, that’s not all of the lead I removed — but it is probably the vast majority of it, since I did the removal over a sheet of paper using a rasp, and then weighed the shavings (which turned out to be 10.5 grains, btw).

That cartridge feeds fine in my levergun. No problems. So the trick will be to experiment with seeing how little lead I can remove while still getting reliable feeding, and getting good at doing so uniformly so as to not really screw up how the bullet behaves aerodynamically. That should be a manageable matter. (Edited to add: see my solution here.)

But I also think I’ll drop Buffalo Bore a note, and see if I can get them to tweak the design of the bullet just a tad to make it more friendly for us levergun owners. Thanks to BBTI, I should have enough cred that perhaps they’ll take note.

We’ll see.

Jim Downey

August 1, 2013 Posted by | .44 Magnum, .44 Special | , , | 8 Comments

   

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