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Steyr Mannlicher Schoenauer Model 1956

B-ARFCOM member Probablecoltaddict picked up one of these finest bolt action sporting rifles made and and shared these great pictures .

a brief look at what I consider to be a well used yet well preserved example of a Steyr Mannlicher Schoenauer Model 1956 with factory installed scope mounts and a vintage Weaver K4-F telescopic sight.  

First up are the right and left side general views of the rifle:

Next up are some markings starting with the manufacturer on the left side of the receiver:

From left to right on the barrel left side we have an inspection stamp, nitro proof stamp and year of manufacture (1957):

On the front left of the receiver we have an inspection stamp and the year of manufacture again:

On the bottom of the magazine we find the STEYR logo and the importer/US distributor, Stoeger:

At the top front of the receiver, there are more markings but the scope is in the way so it’s difficult to get a good shot of them.  Fortunately, this rifle was ordered with factory installed, quick disconnect scope rings.  So let’s get the scope off to get a look at those markings.
We start at the left rear of the receiver where we find this curious little mechanism (rear is to the right):

Notice the blued rectangle in the center of the frame with a “U” cut out of it.  This is side of the mounting block for the rear scope ring.  The block  is held fast to the receiver with two slotted screws, one of which you can see to the left.  There is a slot cut into this block from above to allow for a bare steel piece that also has a “U” cut in it.  This piece slides back and forth and is held in place by two pins, the heads of which are visible on either side of the “U” cut.  Additionally this sliding piece is pushed to the rear under spring tension and can be seen sticking out from the rear of the mounting block, forming a push button. To remove the scope, simply press forward on this button with the finger or thumb of one hand (thus lining up the “U” cut in the sliding piece with the corresponding one in the mounting block) while grasping the rear bell on the scope with the other hand and swinging it clockwise when viewed from above.

Once the bottom of the scope ring is free of the mounting block, release the push button and you have a situation as shown below:

Notice that there is a slotted screw on the ring where it fits into the mounting block.  There is one on the other side too.  These screws allow you to both make course windage adjustments and perfectly fit the ring to the mounting block so that there is zero side to side play.  

Next, continue to swing the scope in a clockwise arc until it is positioned 90 degrees relative to the rifle:

Then you simply lift straight up on the scope to remove it from the rifle entirely.  You may have to wiggle it a bit because it’s such a perfect fit.
Here is the mounting lug on the front ring:

And the front mounting point on the rifle:

notice the raised areas to the rear of the mounting lug hole and on the right side of the mounting point.  These are slotted and engage with lugs on the scope ring to lock it down as you swing the scope into the mounted position.

An above view of the rear mounting point with scope removed clearly showing the retention and release mechanism:

At the rear and similar to the front mounting point, we have a raised area with a slot cut to lock the scope ring down.  This system locks the scope on as tight as if it were screwed to the rifle and guarantees a perfect zero no matter how many times the scope is removed and replaced.  I mean it is rock solid.

And now that we have the scope out of the way, we can get a look at the markings on the front receiver ring:

Notice how perfectly struck the lettering is.  SCHWEET!!  Also notice the fine stippling applied to reduce glare when using open sights.  To a guy like me used to military grade firearms, this stuff is pure Art!!  These were available in various calibers, some of which are a real pain to get these days.  While I would have bought this thing no matter what caliber it was in, .308 was a nice bonus since I have a number of rifles in that caliber already.  Back in 1957, .308 Winchester was a pretty new thing!

Next, we’ll take a brief look how you remove the magazine and the magazine itself once removed.

Here we see the bottom of the magazine when mounted into the rifle, front being to the left:

Notice the total loss of bluing forward of the STEYR logo.  This leaves no doubt as to how the owner held this rifle.  He must have had similar sized hands to mine because I noticed that when I aim using this same hold, my second finger just touches the right side of the receiver ring.  I didn’t take a picture of it but sure enough, the bluing is rubbed off in that spot.  I live for little details like that.  It’s History literally imbued into the firearm itself!
Alright, back to planet Earth…..
At the front of the magazine base plate is a little circular hole through which you can see bare steel.  This is the dismounting catch.  Insert the tip of a cartridge into this hole and press down slightly while rotating the base plate in either direction.  Below, we see the process just started with the base plate rotated enough that the catch has been disengaged:

It’s important to note that the dismounting catch does not secure the magazine to the rifle; that is accomplished by tongues at the front and rear of the base plate engaging slots cut into the bottom of the action.  Rather, the dismounting catch only secures the base plate from rotating.  

Now continue to rotate the base plate until the aforementioned tongues are clear of the slots in the action (rotating 90 degrees as shown is best):

Now, use the base plate as a handle and lift the magazine out of the stock revealing the inside of the receiver and the bottom of the bolt:

Lots of interesting things are going on up in there but that’s a subject for a different time.

A left rear 3/4 view of the removed magazine:

And a right rear 3/4 view:

If you aren’t familiar with the Schoenauer magazine design, you’ll be baffled at this.  That’s because it’s not a box magazine but rather a rotary 5 round design.  as you load them from above, they spool around the central axle.  There is no follower in the traditional sense and none of the rounds touch each other when the magazine is loaded.  It’s a complicated but elegant design that is reliable and efficient.  It is also part of the reason the action on these rifles is renowned for how smooth it is in operation.  Normally, there is no reason to remove the magazine from the rifle unless you want to clean it.  Unloading of a fully or partially loaded magazine is achieved by opening the bolt and pressing a button which then allows the cartridges to spill out from the top.  Never unload a magazine by removing it from the bottom.  It won’t be pretty and you may end up damaging something.  

If you wish, the rotor can be removed from the magazine by pushing the rear of it forward and then lifting:

Because these rifles could be ordered in multiple calibers, magazines are specific to the cartridge being used.  The rotor is caliber marked:

The magazine body is also caliber marked on the inside:

Here is a top view of the action with the bolt to the rear:

The lozenge shaped checkered button is used to empty the magazine.  Simply push it and whatever is in there comes flying out the top.  For such a refined design, it sure dumps out the rounds in a most undignified way but it is fast so it has that going for it.  A keen eye will also see the rotor.  There are a few other things going on but this is just a brief overview so we’ll leave it at that.  However, I do want to point out how beautifully finished everything is.  Most of what you are looking at is in the white yet there isn’t even a hint of discoloration after 63 years.  That’s a combination of extremely good steel and extremely good maintenance!

Let’s us 3D print a gun – Part 4- It’s alive!

Fun stuff first.

I took the 3D printed lower to the range and tested it out. Ran fine.

When I first was thinking about doing this project, I expected to 3D print a gun, then shoot it until it broke. After I printed the Gluty lower, I realized if I tried to do that I would end up shooting all my ammo, that would be kinda hard to replace right now.

I fired 190 rounds, I stopped because the handguards got very hot. I did have a couple of minor issues. The first mag I tried was a Lancer mag (I think they have a new generation, if so, this is a first gen mag). I over inserted it and had a hard time removing it from the gun. So I didn’t use the Lancer mags, and instead used a USGI mag and four Magpul 40 round mags. One of the Pmags did not have the follower come up completely causing the bolt to fail to lock to the rear upon firing the last shot. I would call this a mag problem, not a gun problem. I’ve previously reported about having these issues with my Magpul 40 round Pmags.

I have no doubt, that with quality magazines, I wouldn’t have had a single issue.

Now let us back track.

I was printing the Gluty 9mm pistol. It would use a Glock barrel and mags, and the bulk of the chassis would be printed. While the bolt is in a printed shell, it is mainly a big hunk of steel rod with a notch cut out of it and holes drilled though it. The work can be done with a Dremel and drill press, but most of my tools are packed away in my horder’s nest, so I decided to pivot to a simpler project. An AR15 lower.

There are a number of good options. I had a hard time picking which one to print, finally picked the “Aliamano Phobos AR-15 lower”, made by ArmaDelite, which is “based on the JT-Vangard and Phobos models”.

This one was picked because it looked like it would be easier to print than some of the other options. I don’t know if that is truly the case, but it is why I picked it.

I was able to print it in a single piece, out of PLA+ filament.

Online, you can find many a person who says that ABS would be the better choice for printing a firearm. But when you read reports of people who are printing firearms using FDM printers like mine, they talk about ABS been weak along the layers and needed acetone or MEK welding, or other reinforcements. I’ve never worked with ABS in printing, so I decided to try PLA. That is also what I had on hand and I wasn’t about to spend money on this project.

I don’t so much printing with supports, so I tried settings the support material to be printed at a 45 degree angle to the main part. I hoped that would make it easier to remove. That was a mistake. Instead of peeling off in large chunks, the support material came off in very small pieces and I spent about 8 hours taking this print from the state it was off the printer, into being an assembled lower.

Pretty much all the holes had to be drilled out to size. With the exception of the firing pin holes, those came out perfectly in spec.

After 6 hours of scraping and peeling away support material bit by bit, the lower was still covered with it.

The worst part ending up being the threading where the receiver extension (buffer tube) goes. Some of the support material at the top would not come out at all. I finally had to take a sanding drum for the Dremel, melt away much of the plastic, and use a receiver extension to tap all those threads. That was miserable work, and I was afraid I was going to scrap the lower. I even got ready to print another one with different settings right before I finally got the receiver extension to screw in all the way.

I ran into a few other problems as well. The slot for the magazine catch printed undersize and I had to spend a while with a file to clean it out. Then I found the cheap old parts I had laying around were screw up.

I don’t know what brand that is, but it is a plastic mag release catch button I pulled out of an old AR15. It screws onto the match catch crooked.

So the mag release on this gun binds slightly. It works, but not as smoothly as it should. I could spent more time filing away plastic to account for this out of spec button and the tight slot in the lower, but it works. I’m not looking for perfection here, just functionality. “Anything worth doing, is worth doing poorly.”

The other issue I ran into was that when I went to tap the grip screw hole in the receiver, the tap I used just ripped the plastic out of that hole. Reaming it out over sized. I started to try a couple different solutions, finally decided to go an easy route and printed up an AR15 grip and glued it to the lower. I left out the spring and detent for the safety and I didn’t want to permanently leave them in this lower, and the safety is already quite stiff as it is.

A crummy fix, but it works, and that is the goal here.

Aliamano Phobos AR-15 lower

If I were to complain about this lower, I would have two main gripes. It is not compatible with an upper that has a forward assist, and the trigger guard is a little thin for something 3D printed, and I believe it would break under abuse. I feel like I could break it by hand. It wouldn’t stop the lower from functioning, but it could be much beefier.

A smaller issue is that the reinforcement make it a little harder to access the safety. I was able to quickly access the safety for rapid shooting drills, but it is no where near as easy as on a standard lower.

The massive reinforcement where the receiver extension screws into makes installing the receiver extension a major pain. I placed the receiver extension in a vise and use a wrench on the lower to turn it. Took a lot of effort. I was worried the lower would break. Turned out fine.

But the receiver is really wide in the back. You will want to use a larger, satellite dish sized, charging handle latch. I read that other people who have printed AR lowers tend to be fond of using side charging handles on them

“That just sounds like an AK with extra steps.”

This lower has a very cut away magwell. Over the years I have seen several ARs with cut away magwells and they have all functioned fine. This one is even more cut away. Inserting a magazine I found I could move it a fair bit side to side or tilt it forwards and backwards. So when shooting the gun, I tried tilting the mag back, forwards, left, right, and to the extreme diagonals, but I was unable to induce a malfunction during rapid fire.

I have no doubt this lower could withstand short term heavy use. But PLA degrades with time. Some like to push that PLA is better for the environment because it is biodegradable. Time, humidity, and high temperatures will all make PLA degrade faster. But it still is a plastic, and it won’t completely biodegrade any time soon under normal conditions.

I looked into the longevity of PLA printed parts, and I couldn’t find any hard numbers. I do know that stuff I have printed in PLA seems to get more brittle over time. So I am going to stash this lower away for a while and see how to holds up a few months from now.

It is likely that a PLA lower would hold up for several years.

Still for the time and effort involved, I think 3D printing firearms is more an exercise in novelty than a practical production. It does help show the futility of anti-gun laws.