Ballistics by the inch

EMP4 can’t handle the pressure.

Earlier this month I took my EMP4 out to the range, and ran into problems documented in this post. My conclusion:

Since I haven’t had any problems with my standard-pressure reloads, I’m assuming that it’s the over-pressure which is causing this problem. Both the Underwood and the BB ammo are *really* hot. But I wanted to check everything out again before shooting the gun any more. If everything looks good, then I’ll start with standard pressure loads and then slowly step up to hotter loads. I expect that will resolve the issue, and I don’t mind carrying SD ammo which is a little less powerful — shot placement is more important than power.

With one thing and another, it’s been a busy month, and I didn’t have a chance to get back out until this morning to test my conclusion. But first I did a thorough cleaning of the gun, pulled the firing pin and examined it closely. One possible problem could have been the firing pin having sharp shoulders, which could have led to it punching too hard into the primer metal. But upon close examination the firing pin looked perfectly normal and very much like every other firing pin I’ve ever seen.

In preparation for going out to the range today, I picked up some additional good self-defense ammo and grabbed a box of standard factory target ammo:

Starting on the top left (all 9mm Luger ammo, of course):

I started with the Remington, and ran a couple of mags through the gun, examining it closely between reloads. No problems.

Then I switched over and shot each type of ammo, a full mag (9 rounds), again checking the gun between reloads. It ran absolutely flawlessly with each and every kind. I checked some of the spent cases of each type, and all of them showed a perfectly normal primer strike.

Then I loaded up a mag of the Underwood 124gr +P+ I had shot previously. The first couple of rounds were OK, though I checked the spent cases and saw that the primers were completely flattened — the firing pin strike was still visible, but it was no longer an indentation. That’s a sign of too much pressure in reloads, and something you always check when you’re working up a powerful load. The next shot was similar, but there was a missing disk of metal on the primer, which was stuck on the firing pin of my gun. I popped it off, shot the next round. Same thing happened.

I unloaded the gun and the magazine, put the rest of the Underwood ammo aside. Then I loaded it with the Buffalo Bore 124gr +P+ SD ammo. Basically, the exact same thing happened, though I think I made it through three rounds before the first punched-through primer. Again, I unloaded the gun and the magazine, and set the rest of the Buffalo Bore ammo aside. Again, I checked the gun thoroughly to make sure everything looked right. It did.

Then I went back and tried each of the lower-pressure ammos again. Each again ran flawlessly.

I could do more testing, but I’m convinced: the problem is that the +P+ ammo is just too damned hot for the EMP4. Now, my other 9mm guns do shoot it fine (even the little Boberg, which is really picky about ammo), so I guess I could say that the EMP4 is somehow flawed in design or construction. And if you want to hold that against the EMP4, then go right ahead.

But I’m happy enough with the gun otherwise, and there are plenty of types of good self-defense ammo available which are just a little less powerful. Works for me.

 

Jim Downey

 

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August 30, 2018 Posted by | 9mm Luger (9x19), Boberg Arms | , , , , , , , , , , , , , , , , , , , , | 2 Comments

Review: Sterling PPL .380 ACP

Sometimes it’s a good thing to look back at failed experiments, to better understand how we got to where we are today. It can be instructive, as well as cautionary — what we think of as innovative and brilliant now might well look a hell of a lot different in 30 or 40 years.

Such is the case with the Sterling PPL, a small self-defense handgun built and sold for just a couple of years in the early 1970s. Here it is:

A fairly complete story of the Sterling can be found here. There’s not a lot to tell, though it does give a nice description of the gun:

It is a blow back operated, semi-automatic pistol that is chambered for the .380 ACP(Automatic Colt Pistol) cartridge. This pistol incorporates a blade type front sight and a V notch rear sight, both of which are not adjustable. It is fed by an 8 round detachable box magazine. On the pistol’s butt there is a European style heel magazine release. The push button manual safety is located toward the front and directly above the trigger guard. In the photograph on the right, this push button safety is shown in the fire position. The plastic grip panels are secured to the frame by two hex or Allen key screws with a hexagonal socket in the head. The left grip panel will need to be removed in order to disassemble the pistol. This pistol has a one inch barrel and a total length of 5.38 inches and an unloaded weight of 22.5 ounces.

This past weekend I had the chance to shoot this gun. It was an original, but was “New, Old Stock” — while it was indeed made back in ’72 or ’73, it had never been fired and was still in pristine condition.

It’s a solidly made little thing, and while it was clearly not intended to be a fancy, high-finish gun it wasn’t bad in terms of fit & finish. All the parts were tight, well machined, and worked together well. The plastic grips were fitted well to the frame, and the checkering and emblem were clean, sharp lines — not the cheap sort of injection-mold grips which were common on many small guns of that era. The sights were milled into the top of the slide & barrel, and were reasonably clean and low-profile while still functional. The one magazine we tried fit flush into the gun, with no slop. The trigger was better than I expected, though like most of the gun would probably improve with some use. All in all, it really didn’t feel bad in the hand, and the ergonomics were better than I expected, particularly given the small size of the gun and my large hands.

Shooting it felt more natural than I expected, with the fairly high weight taming recoil — remember, this thing weighs more than twice as much as most micro-.380s do today. In fact, it felt a lot like shooting my Boberg XR-9 9mm, which isn’t surprising: compare how the guns look side by side:

And when I laid one gun on top of the other, they were nearly identical.

But the Sterling PPL isn’t the 70’s version of the Boberg. Note that the barrel in front of the cartridge is just 1″ whereas the barrel on the Boberg is almost 3″ in front of the cartridge. That means that the BEST you could hope for out of .380 ACP ammo would be under 200 ft-lbs of energy, while the Boberg (or the current Bond Arms version) would give you more than twice that.

And that extremely short barrel on the Sterling led to another problem: keyholing. That is where the bullet doesn’t have enough time to stabilize (which is the function of rifling in a barrel), and so tumbles. You can clearly see that in four of the first five shots we fired, in this target:

All five of the next shots also keyholed. And that means that the bullets would hit the target in such a way as to minimize penetration, rendering them much less effective in terms of ability to incapacitate. Which is very much not what you want in a defensive handgun.

So it’s not too surprising that this design didn’t succeed, even though it was a very compact little gun. But I do wonder whether if they had extended the barrel another inch or so, would it have survived?

Speculating a little more … what do you think the chances are that the design of the Sterling might have somehow inspired the Boberg? The size, shape, and appearance of the guns are surprisingly similar. Hmmm …

 

Jim Downey

April 2, 2018 Posted by | .380 ACP, 9mm Luger (9x19), Boberg Arms, Discussion. | , , , , , , , , , , , , , , , , , , , , | Leave a comment

First date with the Boberg XR9-S.

As I noted a couple of weeks ago, I picked up a ‘little brother‘ for my Boberg XR45-S. Here they are again:

Lil brother

Well, we’re having another delightful warm spell here in mid-Missouri, so yesterday afternoon I took advantage of it and went out to the range to give the little guy a try.

As I noted before, I have actually shot this particular gun a couple of times previously, and just loved it. But it had been a while, and I couldn’t remember specifically what ammo types we had used. So I packed up what variety of 9mm loads I had on hand, along with my chrono, and went to see whether anything had changed.

Because of the way they operate, the Boberg pistols have a tendency to be very particular about what ammo they like. Ammo which doesn’t have a sufficient crimp is prone to separate (the case being jerked away from the bullet). It’s an issue which is well known, and there’s a list of compatible ammo for both the XR9 and the XR45. But while those crowd-sourced lists are useful, the final word is always what specific ammo your particular gun will handle. For me, that’s particularly something I want to determine for any self-defense pistol before I will carry it.

Full details to follow, but for those who just want the short version: oh baby! The XR9 ate everything I fed it without a problem. Including my standard 9mm reloads. No mis-feeds. No bullet separation. No problems. And it was a real joy to shoot, which isn’t something I normally say about a pocket pistol handling full-power SD loads.

OK, for those want the details …

Below are informal* chrono numbers for seven different ammo types I had. These are all for the Boberg. But I also ran a few through my Steyr S9 for comparison, which usually just had an advantage of about 10 fps over the Boberg (the barrel on the Steyr is about a quarter of an inch longer). If that much.

  • Buffalo Bore 124gr JHP +P+                                             1,230 fps
  • Federal 124gr Hydra Shok JHP                                           1,025 fps
  • Reloads. (4.4gr HP-38, 124gr Rainier FMJ bullet)                        1,020 fps
  • Remington 124gr FMJ                                                       1,040 fps
  • Speer GDHP 115gr JHP                                                      1,210 fps
  • Speer GDHP 124gr JHP                                                      1,100 fps
  • Speer GDHP 124gr JHP +P ‘Short barrel’                           1,150 fps

As you can see, all pretty respectable numbers. And in keeping with both the claims of the manufacturer as well as what we had tested previously (where there’s overlap). I wouldn’t have any qualms carrying any of the Speer ammo, but my preferred SD ammo is currently the Buffalo Bore. Happily, the Boberg shot all of them without a glitch. And after getting my chrono numbers, I ran several magazines worth through the gun doing some quick shooting at cans, was getting excellent accuracy from it at about 15 yards.

I brought it home, stripped and cleaned it, and now consider it reliable enough to carry. Of course, I will continue to practice with it regularly, and keep a close on on how it performs with my reloads, and occasionally run a mag of carry ammo through it, but I don’t expect any problems. It’s a nice little gun.

Jim Downey

*By ‘informal’, I mean just using one chrono and without the lighting rig we now use for formal testing. And I would just run a magazine of ammo through, mentally noting the numbers in a running tally, then writing them down for that particular ammo, so they are necessarily just ‘ballpark’ figures. But since they jibe well with our previous numbers and what the mfg claims (which I only discovered when I sat down to write this), I think they’re pretty good.

January 20, 2015 Posted by | 9mm Luger (9x19), Boberg Arms, Data, Discussion. | , , , , , , , , , , , , , , , , , , , , , | 1 Comment

Boberg XR9-S: a new little brother for my XR45-S.

As Frank said on Facebook this afternoon:

I knew when you got the 45 you wanted the 9mm too. It was only a matter of time.

Guilty as charged. Look what followed me home today:

Lil brother

Yup, a Boberg XR9-S: a new little brother for my XR45-S. As I did in that post, I thought I’d put up some comparison pix to give a sense of just how small this gun is, even though it really doesn’t feel like it when you hold it or shoot it.

Here it is again with the XR45:

Lil brother 2

And here’s the view that shows the thickness of both:

Top

Yeah, there’s a difference. Here’s the XR9 with a Springfield EMP (also 9mm, 3″ barrel – the XR9 has a 3.35″ barrel):

W EMP

 

And with my J-frame in .38 Special:

W J-frame

For grins, here it is on top of the J-frame:

J Top

OK, but how about in comparison to the classic premium pocket 9mm, the Rohrbaugh R9? Here ya go:

W R9

The R9 *is* a fantastic little gun, and I love it. I don’t love shooting it, though. The XR9 wins in that category. It will also handle +P ammo and holds one more round (7+1) than the Rohrbaugh. But it is a bit bigger:

R9 Top

Lastly, here it is with a Bond Arms derringer — a great little gun, with a variety of different barrels available. But there’s still just two shots in the derringer, and it actually weighs about 3 ounces more.

W Bond

While I have shot this gun (it belonged to a good friend), and know it to be dependable, I do still want to make sure that it will be able to reliably digest my preferred SD loads. So more on that to come!

 

Jim Downey

December 26, 2014 Posted by | .45 ACP, .45 Super, 9mm Luger (9x19), Boberg Arms, Discussion. | , , , , , , , , , , , , , , , , , , , , , , | 1 Comment

Boberg XR45

I’ve written about the innovative Boberg Arms XR9 previously. Here’s the take-away from my review:

This gun is a winner. It is well designed, and well made. The innovative design makes your brain hurt when you first see it. But the recoil is nothing like what you get from any other “pocket gun”, even when shooting full +P defensive ammunition. Usually with a pocket gun, you trade off the pain of shooting it a lot for the convenience of being able to carry it easily. With the Boberg, you don’t have to make that trade-off. I honestly wouldn’t be bothered at all by running a couple hundred rounds through this gun at the range.

Well, guess what followed me home today.

No, not an XR9. Something a little … bigger:

Case

Yup, one of the new XR45s.

Here’s a pic of one from my outing with the other BBTI guys a few weeks ago:

XR45S2

It’s a little hard to tell how big the gun is in that pic. Here it is with some others:

all 4

Starting in the upper left corner and going clockwise, those are: A Steyr S9 in 9mm, a Springfield EMP in 9mm, the Boberg XR45 in .45ACP, and a S&W J-frame in .38sp.

Here’s the Boberg back to back with the Steyr:

with S9

With the EMP:

with EMP

And with the J-frame:

with j-frame

And just for grins, here’s the Boberg with the J-frame sitting right on top of it:

on top

Yeah, the 6+1 Boberg is actually smaller than the three other compact pistols. And it has a longer barrel than all three — 3.75″ on the Boberg, compared to 3.5″ in the Steyr, 3.0″ in the EMP, and 1.875″ on the J-frame.

How does it do this? Because of the innovative … some would say just plain weird … way the feed mechanism works. For the best explanation, take a look at the animation on the Boberg homepage, but basically as the slide comes back, it grabs a new cartridge out of the magazine by the rim and then positions it into the chamber. Yeah, you put the bullets in the magazine nose first. Like this:

with mag

And here’s a detail of the top of the loaded mag:

mag loaded

It takes some getting used to, I admit.

Now, while the Boberg is actually smaller in overall size than the other guns, it still has some heft to it: 22 ounces, as opposed to both the Steyr and the EMP at 26. The J-frame shown is a Model M&P 360 with the Scandium frame, so it comes in under 14 ounces. All of those are unloaded weight.

How does it shoot? Like this:

“Not bad at all.”

That was with .45 ACP+P high-end self-defense rounds.

Since I just got mine, it will take a while to find out all the little quirks that it has. But based on shooting one a few weeks ago, and in a much longer session with the 9mm version, I have little doubt that I will be very pleased with it. I’ve already poked around my selection of holsters, and found that the XR45 fits perfectly into a little belt slide holster I have for my Glock 21 Gen 4, as well as into a Mika Pocket Holster I use for the J-frame.

Jim Downey

December 6, 2014 Posted by | .38 Special, .45 ACP, 9mm Luger (9x19) | , , , , , , , , , , , , , , , , , , , , , , | 7 Comments