MAB Pistol

I had the opportunity to inspect and repair a MAB Model D, Type II semi-automatic pistol that was not functioning. The customer told me he had searched for anew mainspring as the one in his pistol was broken, without any luck in finding an original or newly-manufactured replacement. I told him that I had quite a number of parts companies I could check with, so he gave me the green light to try and repair this old specimen.

It was in fairly decent shape, other than the sear spring—also known as the mechanism spring—was broken. I began by removing what was left of the sear/mechanism spring and taking photos of it, then checking with nearly 20 different parts companies to find if they had an original or replacement in stock. I was able to locate one for the Type I pistols, listed as "the wavy spring", but not one spring (new or original) was located for this Type II model.

I did some research on MAB pistols and was not able to find detailed disassembly instructions for it, other than the routine disassembly instructions for cleaning and maintenance. No owner’s manual was found, either, though I found some historical information. It seems that a gentleman by the name of Leon Barthe, born in Saint-Vincent-de-Tyrosse, France, began making MAB pistols in 1921. It has been written that the initials MAB were taken from his business named " Manufactured Armes de Bayonne ".

He later died in 1937. MAB pistol models made over the years included the Model A, B, C, D, E, F, G, and R, and all were categorized as inexpensive personal protection guns. Research found that there were two versions of the MAB Model D pistols made; the Type I and the Type II. The MAB Model D, Type I pistols were reportedly manufactured between 1933 and 1945. The Type I had a muzzle bushing release latch located in front of the trigger guard.

The Type II has a bushing with two lugs on it that can be removed by pushing in on the barrel bushing and rotating it counter-clockwise about a quarter of a turn to release and remove it from the slide. Production of the MAB Model D, Type II pistols reportedly began in mid 1945. Based on my research, the pistol in my shop for repairs was produced during or after 1950, due to the serial number stamped on the pistol (SR# 83,xxx).

The MABs, depending upon the particular model, came with a blued or nickel plated finish, and in .22 Long Rifle, 6.35mm (.25ACP), 7.65mm (.32ACP), .380 ACP (9mm Kurtz), and 9mm ACP calibers. It seems that there is a book about these guns but written in French. I found one detailed schematic for the MAB Model Dlocated on the Numrich Gun Parts website. Therefore, I used the naming conventions listed on their website when identifying each of the pistol parts covered in this article. 65mm caliber.

This pistol was purportedly produced after March of 1950 according to limited information found. Since this particular pistol still had half of the sear/mechanism spring still in the receiver, I was able to identify it as being for a Model D, Type II pistol. Unfortunately, a mechanism spring specifically for the Type II pistols could not be located for this repair job—new or otherwise.

While inspecting the spring removed from the gun, I decided to take photos and measurements of it, mainly so I would have a starting point if I needed to make a replacement spring or had to send specific measurements or photos to a parts company to verify the size and characteristics of the spring they might have on hand. The mechanism spring removed was missing one leg that applies pressure directly to the rear of the connector.

The other leg of the spring that applies pressure to the tumbler assembly (sear side) was

The barrel bushing is removed by pushing inward and turning counterclockwise a quarter of a turn, then pulling the bushing and recoil spring out of the slide. Far The similarities between the two enabled the author to create a spring from the Wilson Combat Number 417 Bullet Proof Spring. found unbroken and in good shape, therefore, I was able to measure it fully.

Measurements taken found that the flat-styled spring had an overall width of 0.421" and the tumbler assembly or sear leg side of the spring had an overall length of 2.665" long (measured from the base of the spring to the tip of the leg). That same leg was measured for width and found to be 0.135" wide at the base and 0.100" wide at the top and bent forward some at the very top. Since the left side of the spring leg was completely broken off and missing from the pistol, I wasn’t able to take those measurements.

The overall thick- This side view shows the overall length, the curve of the spring, and the reverse bend at the top of the spring leg that applies pressure to the rear of the connector. ness of the entire spring was found to be 0.020" thick. Knowing these measurements, and looking at the broken spring, I quickly realized that it closely resembled a 1911 sear spring with two legs instead of three. Looking over my inventory of 1911 sear springs, I found one would fit fairly well.

It was a brand new Wilson Combat Number 417 Bullet Proof Sear Spring. The reason it would work was due to the overall size of the pre-made spring (length of the legs, thickness, etc). Not wanting to waste any more time looking for a replacement, I began making anew spring from the Wilson Combat product. I began by coating the 1911 spring with layout dye and then tracing the outline of the broken spring I had onto the Wilson spring with ascribe.

After tracing, I clamped the Wilson combat spring to a small board with a small C-Clamp. Using my Dremel tool equipped with a cutting blade, I carefully cut away the excess areas of the spring that would not be needed. I say carefully because I wanted straight lines and had to keep water on the spring so as not to overheat it during the process. Essentially, you will need to remove the short or grip safety spring leg completely to get the spring down to an overall width of about 0.421.

Then, use a Dremel equipped with a cut-off blade to carefully remove about a third of the full length of the two inside legs (trigger spring and sear spring). What this does is create two spring legs that are spaced apart wider than the stock Wilson trigger and sear

This type of firing pin, or striker, is becoming very difficult to find for replacement. The firing pin spring guide is held in place by a post at the rear of the receiver. There is a small pin or post attached to the far left side of the connector and this post retains the trigger in the frame when reinstalled. spring legs.

The sear spring leg is left full length (only cleaned up and bent forward) and the trigger spring (used to be the middle spring) is shortened enough to bend, creating a rearward angle bend on the tip that fits snug up against the angled rear leg of the connector on the pistol. Back to working the spring. Once all the material not used was removed from the spring body, I began sanding and polishing the It just lifts up and off of the pin shown inside the receiver at the top.

Photo also shows the safety catch assembly to the right and the magazine release button. This assembly is held in place by the two pins shown. Note the newly-made mechanism spring that fits into the frame and is held in place by the backstrap and grip safety assembly. spring, the two arms, and all lines so that it resembled the broken spring and remaining sear leg. I left the other side just as long as the sear leg side because I wasn’t sure how long or wide the other leg needed to be at this point.

Once I had it worked down and looking similar to the original spring, I used a belt sander to remove some of the thickness of the Wilson Combat spring as it was 0.014" thicker. You will want to keep the 90 degree The newly-made spring was then test fitted into the receiver. During my research, I had come across a crude drawing of how the spring legs were supposed to look in the receiver (side view), so I used that drawing as my guide when shortening the leg that fits up against the back of the connector.

After shortening that leg, I carefully bent the end to shape based on the drawing and then shaped the entire spring and legs according to that same drawing. Since I could not get permission to reproduce that drawing for this article, I have omitted it. I then installed the newly-made spring into the receiver. After making a couple of small adjustments, the gun was reassembled and the pistol worked like it was new. The spring was doing the job and the gun functioned flawlessly.

I removed the spring, sanded and polished it completely, cold blued it, and then made final spring tension and alignment adjustments before installing it into the assembled pistol. I then function tested it and it passed all operating and safety tests. And so the pistol was lip formed at the base of the 1911 spring as this pistol has a slot for it to sit in when assembled in the receiver. You may need to make it thinner to fit the slot. operating again.

The most tedious part of the spring leg adjustments were found to be on the connector side (short leg). The spring must be bent backwards at the point just below the angled lower back leg of the connector bar and it should be at the very same angle as the back of the con-

Far The plunger is protruding upwards where the plate was and is under coil spring pressure. The plunger secures the safety catch when turned by popping up into the two pictured holes in the catch. Go easy when installing this screw as the post of it is very short, small in diameter, and fragile! The magazine release button simply unscrews from the retainer plate located on the right side of the receiver. nector.

This is because the spring under tension should push forward and upward against the back of the connector leg at all times. If when working the slide (making it ready to fire) and pulling the trigger the gun won’t fire (or drop the striker) it is due to the connector. When the connector is pushed downward by the slide when pulling the slide back, it needs to come back up into position to fire. The connector must come back upward each time and align the rear of itself to the sear to ensure the gun will fire.

You can perform function tests while making your necessary adjustments with the left side grip panel removed from the receiver during final fitting. Just know that you will need to have the empty magazine inserted into the receiver so that you can pull the trigger during your testing. To aid in the connector doing its job, polish the back side where it rides against the receiver, removing sharp edges and factory burrs.

Then polish the rear angled leg where the leg of the mechanism spring rides up against it and the end of the spring itself. During reassembly, lightly grease the entire backside of the connector, the post that fits into the trigger, the rear disconnector leg, and the tip of the spring where they meet each other. This will ensure a smoother movement from the connector when operating the slide because the slide actually moves the round top of the disconnector downward with every pull of the slide.

The connector has to move back up into position when the slide is closed and the leg of the mechanism spring does this job. Total time spent making this spring was about 30 minutes and the cost of the spring was reasonable, so it wasn’t too cost prohibitive to accomplish this repair. And the customer has a fully operational pistol, made many years ago, now back in working condition.

Since there seems to be a lack of parts available for the MAB product line, I recommended to the customer that he not use the pistol much anymore, if at all. Plus, current production .32ACP ammunition develops pressures much higher today than the 7.65mm ammunition did back in the 1940s and 50s. My opinion is that it is a safer bet not to shoot these old historical guns anymore but it is nice to have one that fully functions.

Since I had this pistol in for that repair and in need of a deep cleaning, I decided to detail strip the pistol for future reference; along with taking specific parts measurements in case another one shows up missing parts or in a plastic baggie after "a brother-inlaw" took it apart for cleaning and couldn’t get it back together! Detailed Disassembly The MAB pistols have a fairly simple design and disassembly of them is a fairly straightforward operation.

No doubt there will be some differences between the models, but for the most part, the pistol will be disassembled similarly. If you have a Model D, Type II in front of you, begin by removing the magazine, making sure it is not loaded. Work the slide back and forth a few times, visually inspecting the chamber to ensure the pistol is indeed unloaded. If it is, reinsert the empty magazine into the receiver and pull the trigger to release the striker, then remove the magazine and set aside.

Holding the pistol in your weak hand, grasp the grips. With your strong hand, push in on the muzzle bushing some and rotate the bushing a quarter turn counter-clockwise to free the two lugs from inside of the slide. Holding onto the bushing, remove it from the face of the slide and pull the recoil spring out and off the barrel.

Still holding the receiver in your weak hand, position that hand so that you can pull the slide back approximately 1.300" rearward so that the barrel lugs can align with the lugs cut into the left side of the slide. Use your strong hand to wiggle the barrel back and forth while using your weak hand to move the slide incrementally back and forth until the lugs in the barrel free them-

selves from the receiver lugs and the barrel can be turned a quarter turn counter-clockwise. What will happen is that the barrel lugs will move into the lugs cut into the inside of the slide. Once that is achieved, you can simply pull the slide and barrel forward and off the receiver. With the slide removed, turn the barrel clock-wise a quarter turn to free the barrel lugs from the lugs in the slide and pull the barrel forward and out of the slide.

Turning your attention to the rear of the slide, if the striker (firing pin) assembly has not already fallen out, tip the slide so that they can be removed. The striker assembly consists of the firing pin, firing pin spring, and firing pin spring guide. The last assembly to remove from the slide is the extractor. Drift the extractor pin that holds it in place, starting on the top outside the slide and drift the pin downward into the bottom of the slide, releasing the extractor and extractor coil spring.

Finally, if you need to remove the rear sight, drift it out of its dovetail from left to right. This completes disassembly of the slide. Moving back to the receiver, begin by removing the right side grip panel first, then remove the left side grip panel second because the left panel contains the connector. Once the grip panel is removed, lift the connector out of the receiver.

You will notice that the front or leading leg of the connector has a pin attached to it and this pin retains the stamped trigger in the frame. With the connector removed, pull the trigger forward and out of the receiver. Note that during reassembly of the trigger, the side of the trigger with the connector retaining hole on it will face upward when the receiver is laying left side up on the bench. Insert the pin on the connector into the hole/stud on the trigger to reassemble them.

Continuing on, lift the sear assembly (tumbler) off the receiver pin that holds it in place. The sear assembly consists of two parts pinned together: the sear and the magazine safety. The pin that retains them together was staked in place on this pistol so they could not easily be separated. With the receiver lying on the bench left side up, use a drift punch to remove the grip safety pin that holds the lower portion of the backstrap/grip safety assembly to the frame.

The grip safety pin is drifted out from left to right. Using your punch, push out the takedown pin midway up the back of the receiver by pushing in on the grip safety while pushing the takedown pin towards the left in the receiver. This takedown pin has ahead on it, so it must be removed from right to left and reinstalled in the same fashion during reassembly.

With those two pins out, remove the grip safety/backstrap assembly by rotating the top of the grip safety up and inward towards the frame, then pull downward until the grip safety comes out. Once removed, separate the grip safety from the lower back strap that had been held in place by a pivot point. Pull the sear/mechanism spring out of the receiver. With the receiver laying left side up on the bench, turn your attention to the safety catch and remove the safety catch screw that secures it to the receiver.

Once the safety catch screw is removed, lift the safety catch plate off the receiver and under it. You will find a safety (coil) spring and plunger still in the frame. Pull these two parts out now. Note, when replacing this assembly do not over-tighten the safety catch screw as it will prevent the safety catch from pivoting properly. Just screw it down enough to make sure the assembly operates as it should.

Adding some red thread locker to this screw to ensure it doesn’t back out or overtighten during use is prudent. Unscrew the release button to remove the magazine release button and assembly. Use your fingers or soft-jawed pliers here, unscrewing the serrated end of the magazine release button on the left side of the receiver.

The magazine release button and the associated magazine release coil spring will come out from the left side of the receiver and the magazine release catch will fall out from the right side of the receiver. To complete the receiver disassembly, remove the lanyard loop. It is held in place with a small pin. Drift this pin out from left to right. You may need to move or re-position the lanyard so the pin can clear the receiver on the way out as this pin serves as a retaining pin only and is not attached to the frame.

Reassemble in reverse. Other than already mentioned above, the reassembly is goes pretty straight forward. I took a few additional measurements while the pistol was disassembled. The magazine release button coil spring was found to be 0.570" long, had an outside diameter of 0.205", and a wire diameter of 0.020". The safety catch coil spring measured 0.335" long, had an outside diameter of 0.100", and a wire diameter of 0.014".

Finally, the safety catch detent was found to be 0.360" long, have a diameter of 0.100", and one end was rounded over. This repair went fairly well. The cost of a Wilson Combat 1911 sear spring and a little labor restored this pistol to operating condition once again. I actually think the heavier Wilson-made spring makes the pistol function even better than the original mechanism spring did or would have, being more heavy duty and pressing harder against the connector.

Hopefully the information shared in this article will be helpful to a fellow ‘smith if or when one of these MAB pistols crosses your bench with a broken Model D, Type II mechanism spring! AG