JPFO's Life Preserver Buoyancy Testing


Jews For The Preservation of Firearms Ownership, Inc.
P.O. Box 270143
Hartford, WI 53027

Phone (800) 869-1884
Fax (425) 451-3959

A Publication of Jews for the Preservation of Firearms Ownership

"Intellectual Ammunition to Destroy Gun Control"

A Detailed Test & Evaluation of the MAS-49/56 .308 NATO Self-Loading Rifle (SLR)


J. B. Hohlfeld

Around October 1998, our good friend Aaron Zelman contacted me about doing a detailed T&E on Aaron's newly acquired MAS-49/56 rifle. Since I was familiar with the MAS-49 SLR from my Vietnam days, I thought it would be an interesting and fun project to do. It is now over one year since this project began, and although it has been "interesting", it has also been quite frustrating for us and Aaron.

(Historical Note: As late as 1968, quite a few of the Montagnard and/or CIDG units were still using the MAS-49 as their main battle rifle. Considering the general size of the Montagnards, the MAS-49 was a good choice of firearm for their needs, compared to an M1 Garand.)

Before I go into our T&E of the rifle, let's go over a bit of it's background. The original design pattern was developed while France was still under the iron heel of Nazi occupation during WWII. Obviously, the design team at the Manufacture d'Armes de Saint Etienne (M.A.S.), had to hide their project, or get hauled away by the Gestapo. With the liberation of France in 1944, they could go forward to completion, hence the MAS-44 nomenclature for France's first Self-Loading Rifle. As you know, France, like most of Europe, was an economic basket case after the war, ergo, the new Fusil Semi-Automatique de 7.5mm Modele 1944, would use the existing 7.5x54mm cartridge, as well as the wood forend and buttstock from their old pre-war MAS-36 bolt action rifle.

By 1948, the French had enough field experience/reports from their Indochine war, that they began to refine the existing MAS-44 design. The old MAS-36 spike bayonet was replaced with a detachable blade bayonet, and an integral grenade launching system was added to the renamed MAS-44A. With further refinements and the addition of a muzzle brake, the MAS-49 was born. From 1951 through 1957, the MAS-49 was the mainstay of all French forces, until it was phased into the MAS-49/56. By 1970, the MAS-49/56 was taken out of active production, and phased out of all front line French military units by the late 1980's.

For those who own a MAS-49/56 in its original 7.5x54mm French chambering, we offer the following data.

According to the book, "Military Small Arms of the 20th Century", 5th edition, the military specification for the 7.5x54mm cartridge:

Projectile Design:FMJ Ball, Flat-Base (non boat-tail), Nickel-Copper Jacket.
Average Projectile OD:.3075-Inch.
Average Projectile WT:147-148 Grains.
Average Velocity:2,425 FPS. (MAS-49, WITH 22-3/4 inch barrel)
Average Chamber Pressure:50,000 PSI (edited correction).

Since Aaron's MAS-49/56 had been rechambered to 7.62x51mm NATO, and we wanted to verify the listed velocity for the 7.5x54mm, this gave our friend Tom Adams an excuse to buy one of the MAS-36 bolt-action rifles for his collection. Using Tom's new MAS-36 with a 22 ½ inch barrel, we got the following chronograph numbers.

Highest Velocity:2,715 FPS.
Lowest Velocity:2,656 FPS.
Average Velocity:2,693 FPS.

We assumed that the difference in the velocities we got was due to our using the MAS-36 locked-bolt system, versus the MAS-49 with its direct gas operated SLR system.

Normally in our T&E articles, I would now give you a quick tour of the fit, finish, and furniture on the firearm being tested, however, due to something we rapidly encountered, I will digress for a bit. We were very curious about exactly how Century Arms had gone about the process of converting their MAS-49/56 rifles from the original 7.5x54mm cartridge to the 7.62x51mm NATO cartridge. A phone call to Century Arms got us the following information:

In all honesty, we found some of this to be a bit curious considering the slight variance in chamber pressures between the 7.5x54mm and the 7.62x51mm NATO cartridges, ie; 50,000 PSI (edited correction) versus 52,000(+) PSI. It was time to go to the range and see for ourselves.

As is the norm here at ROC, the ammunition used for testing was readily available military surplus NATO ball from various sources. For our testing, we would be starting with CAVIM-NATO ball, which gave us an average velocity of 2,744 FPS. Our first couple of shots appeared to be doing fairly well, however, we did notice some case rim deformation in each fired case. By round 12, we were tearing chunks of the case rim off of the fired cartridges. By round 18, Aaron's rifle had become an expensive club, due to the fact that the fired cartridge case was still very stuck in the chamber with the case rim torn off by the extractor, and even a cleaning rod could not drive out the fired case. At this point in our testing we knew one thing for certain, the MAS-49/56 extractor was very well made and rugged! In our minds, Century Arms must have used a very "tired" reamer when they rechambered Aaron's rifle. It was time to see our friend Bill Black at Santa Fe Gunsmithing for a serious chamber polishing job.

As usual, Bill Black came through for us and we had Aaron's rifle back a week later. Off to the range! Using the same CAVIM-NATO ball ammunition which we had tried before, our testing began with flawless functioning until round 19. Once again, we started tearing case rims and had to use a cleaning rod to get the fired case out. By round 29, Aaron's rifle was back to being an expensive club. It was time to clean Aaron's rifle again, change ammunition type and retest. For our next round of testing we changed to Malaysian-NATO ball, which gave us an average velocity of 2,780 FPS. Everything was going well until round 30, which was stuck in the chamber with the case rim torn off. Six rounds later we stopped testing and came to the conclusion that Aaron had bought a lemon. There was only one way to find out, so Tom Adams took this opportunity (excuse), to buy a MAS-49/56 for his military rifle collection. We ordered Tom's rifle through the good folks at SOG International of Lebanon Ohio. Once Tom's rifle came in, it was stripped, cleaned, turned into an expensive club just like Aaron's rifle, and then taken to Bill Black for another chamber polishing job. After another field test, Tom's rifle and Aaron's rifle were both expensive clubs. Something was seriously wrong with this picture! It was time to back away from the MAS-49/56 project and give it some hard thought.

Weeks passed, and the more Tom and I thought about the difference in chamber pressures, the more we thought that this was the heart of the problem. We knew that the rifle had been designed around the 7.5x54mm cartridge, which developed 50,000 PSI (edited correction), while the 7.62x51mm NATO cartridge developed 52,000(+) PSI. If our premise was correct, the rechambered MAS-49/56 rifles suffered from an imbalance in gas pressures, which then caused an imbalance in the cyclic timing of the mechanical system. We started thinking about ways of making an adjustable gas system without doing major modification to the rifle, ie; the KISS principle had to be kept in mind at all times.

As I mentioned earlier, one of the modifications which M.A.S. had incorporated into the rifle was the addition of an integral grenade launching system. A Flip-up, front sight ladder, had been added to the rifle, along with a flip-up rear sight system. The rear grenade launching sight also acted as the gas "ON-Off" control lever. When the rear grenade sight is in the down position, gas is allowed to move directly through the gas tube and into the bolt carrier, thereby cycling the mechanical system. When the rear grenade sight is in the up position, all gas flow to the gas tube is closed off, which turns the rifle into a single shot bolt action. Obviously, this was the area for our experimentation to take place.

For those who are not familiar with the MAS-46/56 gas system, it consists of the following components: (1) Gas block/manifold. (2) Gas valve cylinder. (3) Gas tube. (4) Gas tube housing within the bolt carrier. We started our experiment by removing the rear grenade launching sight system, which was directly connected to the gas valve cylinder. We then fabricated a "control arm", which was attached to the gas valve cylinder, and which was adjustable via a threaded adjustment screw. We could now totally control the gas flowing through the gas block/manifold, through the gas tube, and into the bolt carrier, ie; no gas, some gas, or full gas flow into the bolt carrier.

Though our "control arm" system was quite crude, range testing proved our theory to be completely valid, ie; by adjusting the gas flow going back to the bolt carrier the rifle functioned without a hitch. Without going into detail, Tom Adams and I were able to refine our adjustable gas system so that it was more user friendly and much less complex than our original experiment had been. At this point, Aaron's MAS, Tom's MAS, and a third MAS, were all functional regardless of the type of ammunition we fired through them. (Note: For absolute confirmation of our theory, we brought in the third MAS as a "fresh from the factory control rifle", ie; no polished chamber, no nothing. As expected, the control rifle tore case rims and turned into an expensive club before we added the adjustable gas system modification).

Bottomline, it has been my opinion for may years that any gas operated SLR needs an adjustable gas system due to the variances in ammunition loads/gas pressures. This is particularly true of the "direct" gas systems like the MAS, or the AR15/M16, ie; not enough gas pressure and you "short-stroke", too much gas and you may be beating the hell out of the rifle's mechanical components.

If your MAS-49/56 rifle is not working properly from the factory, which it probably will not, I suggest that you contact Bill Toth (pronounced: Tawth) of Design Systems Technologies, Inc., 570-458-0140. Bill specializes in converting the MAS-49/56 rifle to an adjustable gas system.

Now that you have the full background on the gas problems we had to deal with, you can understand why I said that although this has been an interesting project, I never realized how big it would be, and/or how frustrating, Time to move on…

With regard to the finish and furniture of the MAS -49/56 SLR, it is excellent considering the base price of the rifle. All of the metal surfaces have been parkerized, however, every rifle we tested show signs of use and wear, ie; Century Arms did not do any surface refinish work during their conversion process, so do not expect it if you order one in. Though our three test rifles had plenty of "white spots", mechanically they were in excellent condition as far as quality of craftsmanship was concerned. In other words, the French built these rifles "the old way", and did not cut any corners on the quality of the steel, or machining. With the exception of the front and rear grenade launching sights, there are no stamped sheet metal parts in this rifle, ergo, at 8.5 pounds empty, you know you are holding a rifle. However, when you consider that you are now firing a 7.62x51mm cartridge through the rifle, it is an excellent overall package and easy to handle in the bush.

The two piece forearm assembly, which encases the barrel for about 9 inches, appear to be made from very good quality wood and should provide long term service. The same can be said for the one piece buttstock assembly, which is solid wood, and is configured the same as most rifle or shotgun designs. For the vast majority of our test shooters, the length of pull was a bit short, although our Japanese students thought that the length of pull was fine for them. At some point in time, M.A.S. must have received enough field reports regarding the length of pull problem, that they incorporated a very simple solution to correct it, ie; they designed a rubber slip-on boot, which adds about 1 inch to the length of pull and helps to dampen the amount of felt recoil from the original steel butt plate. If your rifle did not, or does not, come with the rubber slip-on boot, I strongly suggest that you have your gunsmith replace the steel butt plate with a good Decelerator type recoil pad. (Note: Your gunsmith will have to modify the stock a bit for a proper fit, but you will get a length of pull which is best for you individually, and a much more comfortable felt recoil, which will allow you to better concentrate on your shooting skills).

All three of the rifles we tested came with front and rear sling loops and a leather sling. The front sling loop is a steel ring, which is attached to the two piece forearm retaining band. It is a very strong system, with the inside diameter of the steel loop being a generous 1 inch ID. The rear sling loop, is actually a Mauser type vertical steel bar, which is recessed into the butt-stock. Both sling loops are located on the left side of the rifle, which is fine for right hand shooters. The leather sling is a good quality and 1 ¼ inch wide, with a military type sliding adjustment system. Though the sling is not designed to be quick detachable, it is easy to work with and quite comfortable to use.

Before we go into the mechanical functioning of the MAS-49/56, let's take a look at the factory iron sights on the rifle.

Like the AR-15, the front sight base on the MAS-49/56 is a standard military type configuration, which means a centered front sight post/blade, with protective "ears" on either side of it. Again, like the AR-15, the front sight post is only adjustable for changes in elevation. Turning the sight post "clockwise" will lower the post, while turning the sight post "counter-clockwise" will raise the front sight post. According to the M.A.S. manual there are 4-clicks per each full rotation of the front sight post, with each click raising/lowering the point of impact by 2-In. (5-Cm) at the distance of 100-meters. Our field testing proved this to be true and you will find the adjustment system to be "user friendly" for the most part.

With regard to the rear sight assembly, it is your typical "slip-stick" European ladder scale system, which is graduated from a low of 200-meters, to a high setting of 1,200-meters. Instead of the usual -V- notch rear sight, the MAS-49/56 has a windage adjustable "peep-sight" type aperture. Turning the adjustment screw "clockwise" will move the sight left, while turning the sight "counter-clockwise" will move the sight to the right. According to M.A.S. manual, there are 4-clicks of windage per each full rotation of the windage drum, however, on our three test rifles we could only verify 2-clicks of windage per each full rotation of the windage drum. We were able to verify that each click of windage would shift the point of impact right/left by the 1-In (2.5-Cm) at 100-meters, as indicated by the M.A.S. manual. Throughout our field testing we saw no indication that the front, or rear sight, would shift their point of aim due to barrel harmonics/vibration. Bottom line, the iron sights on the MAS-49/56 are very rugged battle sights, but they are not and never will be, target sights.

Even our best shooter, Major Lawrence Lucero, could only get a 1 ½ inch group at 100-meters, from a prone supported position while using the factory iron sights.

One thing which became very clear to us during our accuracy phases of testing on our MAS-49/56 rifles, was that each rifle is quite "ammunition sensitive", and some types of military surplus 7.62x51 NATO ball will out perform other types. We are still not sure if this is due to the MAS-49/56 rifle having a 4-groove, left hand barrel twist, or if it is merely the variances in the ammunition used for testing. In any case, we found that the 147-Gr British,or Malaysian surplus ball ammunition, gave us more acceptable groups on paper.

As with anything else, you will have to run your own test to find the best ammunition for your particular rifle.

OK, now we are ready to disassemble the rifle. Assumptions always leading to trouble, let's first make certain that the safety lever is in the "safe" position. You will find the safety lever on the right side of the rifle and at the front of the trigger guard. If the safety lever is in this forward position your rifle is ready to "fire". Without touching anything else, move the safety lever downward and to the rear of the trigger guard, ie; toward the butt of the rifle. At this point, the rifle is in the "safe" mode. Next, we need to remove the 10-round detachable box magazine. You will notice a spring-loaded latch on the right side of the magazine. Pushing inward on the lower half of this latch will release the box magazine from the rifle's receiver. Once the magazine is unlocked, pull it out of the receiver. While you are looking at the right side of the rifle's receiver, you will notice a large, white, plastic knob, which is the charging handle part of the bolt-carrier. While maintaining total control, pull the charging handle to rear of the rifle, while visually checking the chamber to make sure that it is empty. Once the rifle is "safe" and "cleared", we can begin disassembly. (Note: All during the disassembly/assembly process, make sure that the safety lever remains in the "safe" position, as we don't want "dead hammer fall", which could crack your hammer, or your receiver).

As I go through the disassembly procedure, the rifle is laying across my lap, with the top of the rifle facing upward, and the muzzle pointing to my left. Here we go. At the rear of the receiver you will see a spring loaded latch, which you can push downward, thereby unlocking the top receiver cover from the receiver proper. Hold the unlocking lock down with your right thumb, while you begin pushing the receiver cover toward the muzzle with your left hand. As your left hand is moving the receiver cover toward the muzzle of the rifle, you will feel an increase in resistance to your forward movement. This resistance is due to the fact that the forward movement of the receiver cover is also compressing the recoil spring, which is attached to the underside of the receiver cover. With this in mind, slowly keep pushing the receiver cover toward the muzzle, while slightly lifting upward on it. Eventually, the receiver cover will reach the dismount "cut-outs" in the receiver, and the parts will separate.

Before we move on, let's get a better idea of how the MAS-49/56 recoil system works. While looking at the underside of the receiver cover, you will see a long steel "tube" which "steps-down" to a smaller diameter on its forward end. The long steel tube is the recoil spring guide rod, which is permanently attached to the receiver cover. If you push rearward on the front end of the recoil spring guide rod, you will notice that this is a separate part which is spring loaded and captured within the recoil spring guide rod itself. This small, spring loaded rod, acts as the recoil spring guide rod "buffer", which helps to dampen some of the overall recoil force as the bolt carrier and bolt move rearward during the firing cycle.

With regard to the recoil spring, you will notice that one end of it looks "factory finished", while the other end of it looks like it was rough cut. When I asked Bill Toth about the reason for this, he told me that he had contacted the gunsmiths at Century Arms with the same question, and they had told him that they had cut off 2-coils from the original French recoil springs. Exactly why they had done this, they could not properly explain to Bill, ergo, I cannot give you an explanation either. The only thing that Bill and I know for certain, is that this modification would have helped to further "unbalance" the rifle's functioning. Bottomline, this is one more reason for you to send your MAS-49/56 to Bill, so that he can install his adjustable gas system, ie; without an adjustable gas system on your rifle, the likelihood of parts being "battered" in your rifle is quite high.

Now that the receiver cover is out of the way, you can remove the bolt carrier, the bolt, and the firing pin, by merely pushing the charging handle toward the buttstock and lifting the parts out of the receiver. It is quite likely that the bolt carrier will separate from the bolt and firing pin during this process. If this is the case, merely lift upward on the front of the bolt and remove it from the receiver. At this point, your rifle is "field stripped" and ready for cleaning or general maintenance.

Now that you have the primary components sitting in front of you, let's take a closer look at exactly how they work together. With the bolt carrier upside-down and the charging handle facing you, you will notice the following: (1) The front of the bolt carrier is "cut-out", which allows an ammunition stripper clip to pass through it for rapid reloading. (2) There are two metal "tabs" on either side of the bolt carrier. (3) There are two vertical "ears" on the rear of the bolt carrier. With regard to the two vertical "ears", they act as the firing pin guides and also as "travel stops" for the firing pin. As for the two metal insert "tabs" on both sides of the bolt carrier, they had me going, so I asked a friend who is a master machinist. Tim Olson's answer was quick and simple: "Do you see the "flat" in front of the "ears"? Yes. Do you see the down sloping camming angle in front of the flat? Yes. To save money, the French buzzed their cutter through both sides of the bolt carrier in one pass. Aha! Obviously, the French couldn't leave gapping holes in the bolt carrier, ergo, the metal insert "tabs". It's a good thing to have friends who know what they are talking about!

Ok, while we still have the bolt carrier upside-down, drop in the bolt and firing pin, with the extractor facing toward you. You see exactly how the firing pin is held in place by the two "ears" on the bolt carrier, as you shift the bolt forward and backward. You should also see exactly how the rear of the bolt cams up or down as it comes into contact with the camming cut on the bolt carrier, ie; remember the camming cut that Tim told us about? When the bolt is forward the system is unlocked, as it is during the recoil cycle. When the bolt is to the rear on the bolt carrier, the rear of the bolt is cammed upward into the locked position, as it is when you are ready to fire. All-in-all, a very simple and rugged system.

Wait a minute, are you telling me that the bolt locks against those two vertical "ears" on the bolt carrier? Not at all. So that you have a complete understanding of the system, lay your rifle across your lap, with the muzzle pointing to your left, and with the receiver pointing straight up. Take your bolt, less the firing pin, and drop it into your receiver with the extractor pointing toward the right receiver wall. Slowly push the bolt toward the muzzle end of the rifle. Notice how the rear of the bolt drops down at the rear edge of the magazine well? That hardened steel insert block just on the rear edge of the magazine well, is what locks the bolt in place during firing. Take a close look at the leading edge of the insert block. It should be square and true, with no "rounding" along it's leading edge. If the leading edge of your insert block is "rounded", or "peened", DO NOT fire the rifle. DO contact Bill Toth about his repair services. By the same token, take a real hard look at the lower, rear edge, of your bolt. Once again, this locking surface should be square and true, with no "rounding" or "peening" along the primary locking surfaces. (Note: You are likely to see a small amount of "rounding" and "peening" along the bottom center of your bolt. This is due to the bolt riding over the hammer during the recoil/cocking process. Bottomeline, have your MAS-49/56 inspected by a certified gunsmith, and/or contact Bill Toth).

While you are inspecting your bolt, take a hard look at the ejector rod and your extractor. The ejector rod should move freely within the bolt, and it should not show any signs of excessive "rounding" or "peening" along it's rear surfaces, where it makes a fairly violent contact with the ejector stop pin, which is located along the left receiver wall. With regard to your extractor, inspect it for signs of excessive wear, and/or a "sloppy" fit within the bolt. If your extractor is giving you problems, contact Bill Toth for one of his well made replacement extractors, and while you are at it, get one for your spare parts kit. I should mention that there are few, to no, spare parts currently available for the MAS-49/56. This situation may change in the future, but I wouldn't plan that way.

Let's reassemble your rifle. Our starting position is with your rifle laying across your lap, receiver pointing upward, and the muzzle to your left. Place the firing pin into the bolt and drop the bolt onto the bolt carrier. Take the bolt carrier, bolt, and firing pin, as an assembly, in your left hand, with the charging handle pointing down toward the floor. With your right hand, roll the rifle onto it's right side, so that you are now looking at the outside left receiver wall. With your left hand, place the entire bolt carrier assembly into the rear area of the receiver, and slide the bolt carrier assembly toward the muzzle end of your rifle. If you haven't dropped any parts during this process, roll your rifle back into a vertical position. Now, place the machined end of your recoil spring on to the recoil spring guide rod until the spring seats at the inside rear of the receiver cover. At this point, slide the "rough cut" end of the recoil spring into the "tunnel" at the top rear of the bolt carrier. While pushing the receiver cover toward the muzzle and of your rifle with your right hand, use your left hand to control the recoil spring and the leading edge of the receiver cover. DO NOT exert full downward pressure on the receiver cover, until the rear of the receiver cover is about 1-inch forward of the rear of the receiver. With a bit of luck, you should now be able to push the receiver cover downward and have it lock into the receiver rails. Slowly allow the receiver cover to move rearward until it stops on its own. Using your right hand, push down on the receiver cover locking latch, and the receiver cover should "pop" into its proper location on the receiver. Release the receiver cover locking latch and cycle the charging handle several times to seat the various parts. Move the safety to the "fire" position, and pull the trigger, while checking for a solid hammer fall. You're done.

So, after one year plus and a thousand rounds plus, what do we think of the MAS-49/56 SLR in 7.62x51mm NATO? If the rifle has an adjustable gas system, we can give it a solid Thumbs Up. Otherwise, all bets are off and you will likely end up with an expensive club. In our opinion, once the rifle is properly balanced and timed, you will have a very good "poor man's M1A", which should give you many years of service.

Conversions & Accessories

For those who currently own a MAS-49/56 in it's original 7.5x54mm chambering, but would prefer it in 7.62x51mm NATO, Bill Toth can perform the rechambering job for you. If you opt for rechambering, play it smart and have Bill also install his adjustable gas system at the same time.

For those who own a MAS-49/56, which is already chambered for the 7.62x51mm NATO cartridge, but you aren't happy with the limitations of the 10-round magazine; once again, contact Bill about having your rifle converted to accept 20-round FAL meteric mags.

In talking with Bill today, he mentioned a conversion that he is now doing to the MAS-49/56 firing pin. As you know, the firing pin on any MAS-49/56 is "free-floating" within the bolt. If you are using military ammunition, this is fine. However, if you are using commercial ammunition, or reloads with "soft" primers, your rifle could "double" on you, or even turn into a "pogo-stick". In either case, this is not a safe condition when you have blown primers, or ruptured cases flying around. To prevent this from happening, Bill can convert your existing firing pin to the much safer spring loaded, rebound type system. (Note: During our years of training, I have had to spring-load several of our AR15/M16 rifles, due to their "free-floating" firing pin system and "soft" primers. This has been especially true in the case of our SMG's, which fire a pistol cartridge.

With regard to accessories, there really isn't much out there yet. If you are considering putting a scope on your MAS-49/56, scan Aaron's web-site for a T&E article, which I did in the past on the various scope bases, which were available at that time. [See Test & Evaluation of MAS-49/56 Scope Bases]

Ok, that's it for now. I'm going back to training our students…

My thanks to Mr. Tom Adams for his help in co-inventing the adjustable gas system for the MAS-49/56 rifle.

My thanks to Major Lawrence Lucero (NMSDF), for his feed-back and excellent shooting skills.

My thanks to Mr. Bill Black of Santa Fe Gunsmithing (505-438-4174) for having patience with Tom Adams and me during this process.

For those wanting to upgrade their MAS-49/56 rifle so that it will work, and work well, please contact Mr. Bill Toth:

Design Systems Technologies, Inc.
136 Morehead Avenue
Millville, PA 17846
(Phone: 570-458-0140)

Mr. Hohlfeld is the firearms instructor for Ranger Outreach Center. If youhave comments you may write to:

PO Box 1164
Pecos, NM 87552

Fax 505.757.8456


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