Plastics have come a loooong way in the past 3 decades.

A bit of quick info regarding clear vs non clear plastics. When you ask about strength we need to clarify what you mean. If you are speaking strictly of tensile strength, a glass re-enforced nylon will be stronger than a clear plastic. If by strength you mean toughness, then that is a different story. There are several clear plastics that will be able to endure more impact than your typical black mags, but a lot of the clear plastics suffer from being too soft, creeping(spreading), poor fatigue resistance, and very poor chemical resistance. Polycarbonate is a very tough and clear plastic, but it has poor chemical resistance and gets brittle over time.

If you have any more specific questions about our clear plastic and what it can do, please feel free to ask.

We really didn't. Our primary goal was to create the most all around tough and durable polymer AR magazine in the world. It turns out that being transparent was just a bonus.

No, our mags are more impact resistant in the negatives than most are at room temp.

Define Strong. Do you mean impact strength or tensile strength?

How about UV or chemical resistance?

These are some of the ways magazines made of opaque vs translucent materials will fair differently than each other.

In any case materials have improved greatly in this regards over the last two decades so comparing any current polymer to the old Ram Line (or Zytel M11 mags) type magazines from the 1980s is no competition.

If using a magazine as a substitute for a hammer then lower tensile strength (softer) materials will show less impact damage. As the primary goal of the PMag (and all should be for all magazines) is reliability under all conditions, it is our view that specific geometry, consistently maintained by high "tensile" strength material is the best solution. For this reason we have design philosophies we follow in building a polymer M16 which I will repost here...

Magazine Design Philosophy, Testing, and Performance of Magpul Industries PMAG Magazines for the AR/M4/M16/HK416/M249

Building feeding devices for firearms is not a new endeavor, and many materials and methods of construction have been employed for this task. For many years, conventional wisdom regarding magazine construction was that metal was the material most suited to the task. Although other polymer magazines were attempted previously (Orlite, et. al.), the Magpul PMAG became the first generally accepted all-polymer magazine for AR-pattern rifles after its release in 2007. Early military testing drew some criticisms with performance at sub-arctic temperatures and with window material chemical resistance (In the MagLevel window variant). Rumors, assumptions, and outright incorrect information from this early testing and initial evaluations still persist, despite 7 years of materials, manufacturing, and design improvements to the PMAG product line, and millions of fielded magazines in continuous combat use in the GWOT. Current and ongoing testing, both internal and through third parties can easily and thoroughly dispel these rumors and assumptions from any early data. What follows is an explanation of what the PMAG “is”, why it is made the way it is, and why these characteristics provide significant, concrete advantages for professional use of the PMAG over other feeding devices.

The “Job” of a Magazine

In essence, the purpose of a firearm magazine is to present a cartridge at an ideal, or at least acceptable, orientation with respect to the chamber, at a defined range of acceptable amounts of resistance to being pushed forward by the bolt, and must be fed upward at a defined range of speeds depending on cyclic rate, within a tolerance range. That range of acceptable geometries and pressures can vary somewhat among rifles.

The biggest challenge is maintaining consistency in those variables. If the cartridge is presented the same way, under the same forces, within those windows that are acceptable to the host weapon, every time...you'll have zero magazine related failures. Various geometries and design features aid that end. Specifics regarding our designs and geometry that may not be immediately apparent are part of our body of trade secrets, although many features can be seen in our patents and applications. Other things, like constant curve geometry, lacking in the USGI solution, are visibly obvious. Constant curve geometry allows maximum round stack stability and consistent follower contact until the magazine enters the magazine well, where some straightening of the stack must occur due to limitations of the AR-pattern magazine well, which was originally designed for straight magazines. The 30-round USGI “dogleg” geometry creates round stack instability/lack of support and attendant issues “around the bend” of follower travel. Not all “constant curve” geometries are the same—how the round stack is supported as it makes the transition to the mag well up to the feed lips, and how the follower supports that transition varies across magazines claiming constant curve geometry. This, and other small nuances in many other details of magazine construction all affect reliability.

Through internal testing and the body of external testing that we are aware of, the PMAG GEN M3 has been reliable to an extent that far exceeds any other product or solution. Verification of this claim through additional independent testing is encouraged and welcome. The number one concern in magazine selection has to be reliable function of the weapon system across likely environments and situations. We’ve expended hundreds of thousands of rounds in internal testing, unilaterally as well as side by side with current service tan follower USGI magazines and products from other manufacturers. In both sterile, laboratory environments and under adverse environmental conditions of cold, heat, water, mil-spec dust, etc., we greatly exceed the performance of other options with all ammunition types tested. Almost without exception, interruptions of the firing cycle from firearms in our testing using the GEN M3 PMAG, over the entire body of testing in AR pattern platforms, have been directly attributable to component failure of the firearm (sheared bolt lugs, etc.) or primers which failed to ignite after a positive firing pin impact. Total stoppages for all reasons, including the bad primers and weapons component failure, are in or near single digits per 50k rounds in our testing and the external testing that we are aware of. This kind of absolute reliability, under all conditions, with both AR-based and non AR, but AR magazine compatible platforms (FN SCAR, etc.) has been the goal of the PMAG product since day one, and the GEN M3 product line comes as close to this goal as we are currently capable of measuring.

It’s easy to build a brick of plastic, metal, or any combination thereof that fits into a magazine well and will withstand great abuse. Building an extremely durable magazine with the best feeding reliability possible is another achievement entirely, and one we take great pride in.

Materials

Different materials have different properties, obviously, and they are variably suited to these tasks. We’ve spent a great deal of time testing and examining vast numbers of material, manufacturing, and processing options, both pure and hybrid, and this is the understanding that we have arrived at, which drives our direction.

If a material is too soft, it embeds grit too easily, which affects the upward feeding of the follower and round stack and friction for stripping the round. It will also most likely be malleable, and change feeding geometry through deformation in a drop on the lips...or the side wall. Not a crack...but a bend, and possibly an insidious one that will affect feeding, but not be immediately visible. Soft materials also tend to have problems maintaining shape under stress, (such as the pressure of a magazine spring). Polymers that are quite malleable at room temperature and resist cracking, however, tend to fail horribly at temperature extremes, whether hot or cold. Softer, more flexible polymers also usually exhibit creep, especially in feed lips and potentially in the body itself. This allows feeding geometry to change over time, especially at high temperatures.

Metals resist embedded material, but overall friction with common materials and finishes is generally higher than the RIGHT polymer. (Cyclic rates on the same firearm can be measurably higher with a PMAG than a metal magazine, although PMAGs keep up with bolt speeds associated with cyclic rates over 1100 rounds per minute.) Reduced friction allows the cartridge to feed with less required energy in the bolt carrier, which aids function in adverse conditions.

If a material is too hard, it will shatter. Polymers and even hardened metals, when completely rigid enough to resist any and all deformation, will become fragile. You'll have 100% consistency in geometry, a resistance to embedded grit, and a resistance to deformation, but this material will fail under rough handling.

So, we need a balance of properties within acceptable parameters in all measures, coupled with correct geometry and design features.
The last factor we look at, that is the core of our design philosophy, is "resiliency". This is a "spring" effect, or a desire to return to a rested state/form. Same concept in polymer as in metals, except it’s controlled through composition, reinforcement, and processing rather than hardening/heat treating. Resilient materials tend to perform well across temperature spectrums.

After all our testing, a PMAG is what it is as a very specific balance of these properties. A magazine must be rigid/hard enough to maintain feed geometry without deformation and resist problems from embedded grit. It must be ductile or tough enough to prevent shattering under impacts, yet it must be resilient enough to return to the exact same feed geometry without deformation if an impact is hard enough to deflect the material.

A choice has to be made, in all cases, over whether it is better to deform or yield at various temperatures and forces, based on limitations of the material. Metal bends, or it breaks, and either option likely changes your feed geometry, at least with all currently used materials, whether the metal in question is the entire magazine or a component part of hybrid construction. The PMAG is designed to have the necessary rigidity while maintaining resiliency and durability across temperature spectrums. This gives us great grit performance, consistent feed geometry, and an impressive resistance to any deformation that would cause a magazine to cause or allow a stoppage. There are many other factors in the design, but we are talking purely material properties here.

So...can a PMAG crack? Absolutely, if you try hard enough, with enough force, a crack may appear. Through internal and external testing of the GEN M3 PMAG, this requires impacts or repeated impacts beyond current TOP 03-02-045 testing for firearms systems that we are aware of. It may indeed crack in some extreme cases--however, the forces and impacts required to crack a GEN M3 PMAG meet or exceed those that will deform aluminum/steel feed lips or body material, generally to an extent that will cause enough deformation of the metal to change feed geometry/performance and increase stoppages significantly, if not render the magazine non-functional. The PMAG however is RESILIENT. If it absorbs an impact that will deform other magazines, or even if it does crack, it returns to its exact same orientation and geometry it started with, and certain GEN M3 design features make any damage to or breakage of the feed lips themselves extremely unlikely. We deliberate destroy PMAGS and then test their ability to maintain reliable feeding when cracked or split. A more ductile magazine feed lip material that deforms or bends rather than maintaining resilient form may not crack...but it will likely introduce both simple and complex stoppages into the firing sequence of any firearm into which it is used. Softer, more impact “forgiving” polymer body and feed lip materials have trouble maintaining geometry of feed lips as well as bulging from round stack pressure, creating additional variables. The PMAG is resilient and returns to a set geometry when deflected. Rather than allow deformation that can result in a magazine that may not feed, we would rather accept a crack and a magazine that runs than a softer or more ductile magazine that allows deformation and stoppages.

So...material selection is always a trade off of sorts, although different materials perform better over wider spectrums of environmental conditions. A PMAG does what it does based on the full spectrum of performance parameters, and our efforts to optimize across that spectrum.

The material we use also achieves those parameters with additional goals of chemical resistance and long term stability, including DEET and all other military standard chemical tests. PMAG body, follower, and floorplate materials are completely DEET impervious. Early transparent window material, used in our MagLevel window, showed some susceptibility to DEET, however current window material easily exceeds 24 hour immersion standards in both 40% and 100% DEET concentrations. Humidity, or lack thereof, at both saturated and dessicated moisture levels, are also tested.

Construction

After testing hundreds upon hundreds of material combinations in numerous colors, hybrid construction options, and various reinforcement methods, the PMAG GEN M3 is an all polymer, monolithic body of very specific composition, reinforcement, manufacturing techniques, and design, because that is what has worked best out of all the other combinations tried. We continually test new materials, colors, and construction methods, however, in an ongoing attempt to improve in any way we can.

An all polymer design gives us the resiliency desired in feeding geometry as well as in side walls and general durability. Going prone or falling on a metal magazine body or feed lips can dent the sidewall in a manner that restricts round stack or follower travel, essentially destroying that magazine’s ability to function. Changes in feed lip geometry, as mentioned above, can also occur. Spot welds can also yield, destroying the body integrity of metal magazines or reinforcements. The GEN M3 PMAG is designed and tested to withstand much greater impacts of this nature than competing designs without allowing damage to the internal round stack or follower which would impede function. All-polymer, monolithic construction also prevents any possibility of separation of components required in hybrid construction methods or failure of welds in stamped metal products, and provides significant cost and complexity savings over hybrid construction methods as an additional benefit.

Feed Lip Stability Over Time

There is a common misconception that the dust/impact cover supplied with most PMAG products is in some way required to prevent feed lip creep or spread over time. This is not the case. When initially loaded, the PMAG GEN M3, and all PMAGs in the current lineup, exhibit a tiny normalization of feed lip geometry within a very small window of time measured in days, and then this geometry then remains stable over many years, heat cycles, cooling cycles, and outdoor UV and weather exposure. We routinely load magazines and place them into stable indoor, hot, cold, and outdoor exposure storage to monitor various batches of material. These magazines are occasionally function tested and reloaded with no issues.
As implied by the name, the dust and impact cover is indeed designed to keep debris out of magazines during storage, and to provide an extra measure of feed lip protection for magazines in storage, such as stuffed in an ammo can in a tactical vehicle used in off road operations, or for aerial delivery, kicking containers of loaded mags off of moving vehicles, and the like. This ensures that magazines that may normally be out of sight, not maintained, or subjected to delivery handling that is many, many times the normal testing and usage criteria will perform flawlessly after a quick flick to remove the cover.

Testing These Criteria

Absolute reliability can be tested according to relatively established protocols and fixture firing. Testing rough handling, drop, and impact characteristics from full weapon or magazine drops or abuse, when considering the true purpose of such testing, has to include firing and not merely visual inspection. Although incredibly resistant to damage, due to the aforementioned resilience quality, the PMAG GEN M3 is designed and manufactured to function correctly even if damage occurs. Part of our internal testing protocol is to damage magazines through extreme rough handling and fixtures designed for the purpose, and then evaluate function. If a PMAG retains rounds, and even if it is deliberately split enough to not retain rounds, but is forcibly held together long enough to be loaded and inserted into the mag well, it will feed.

We routinely endurance test individual PMAGs to 200 times loaded capacity. So, an individual 30 round 5.56 magazine must survive 6,000 rounds in a single rifle with no cleaning but routine lubrication. Magazines are completely serviceable after this testing. Additional testing protocols test two magazines to 3600 rounds each with numerous magazine swaps and field firing orientations for usability, catch durability, and “magazine monopod” performance evaluations.

We have Thermotrons for cold-soaking to -60F and heating to +180F for drop and function testing. We fixture and trigger release our drops onto polished concrete for repeatable impacts to evaluate all axes of drop testing, dropping the same magazine up to 16 times to test durability at room temperature and at extremes. We do multi-axis full weapon drops at room temperature, -60F, and +180F. We do function testing on these magazines after the drops.

Field testing evaluations with internal and external assets are used to evaluate the human interface and product usability in actual usage conditions in real and simulated scenarios. We have large bodies of user feedback from real and simulated combat environments.
All magazine products are 100% guaged for dimensional accuracy. Although the processed and manufacturing techniques we use provide for extremely small tolerances, we still hand inspect each and every magazine multiple times before shipping.

All this is mentioned not for self-congratulations, but merely to emphasize that we take the quality of our products very seriously, as we know that a military member, law enforcement officer, or private Citizen may rely on the performance of our products in life-threatening situations. Full test protocols for non-proprietary internal testing are available.

Service Life and Deadline Criteria

As mentioned previously under endurance testing, PMAG service life is extensive, providing performance over high round counts and significant abuse. Numerous first-hand accounts of the same complement of PMAGs being used on 3, 4, or more combat tours and workups in-between have come in from end users. Although service life is long, all magazines are consumables at some point. With a PMAG, if it is not cracked, or broken, it is serviceable. If there is a visible crack, even if the magazine functions, it is time to replace it. Even with significant cracking, however, the PMAG will continue to function as designed until it is split far enough that it cannot retain rounds, as the feeding geometry does not, and cannot change without destroying the magazine. Unlike with USGI or other metal or metal-lipped magazines, it is impossible to have a magazine with damaged feed lips that does not function properly, but appears to be serviceable. PMAGs eliminate the large box of magazines in every armory that appear OK, but create stoppages and have been marked by users and turned in, only to be re-issued in hopes the next user won’t notice. Having a positive deadline criteria saves time, resources, and frustration on the range, and is safer for combat troops.

Cost
This increased performance, features, and all the benefits come at a price that can be entirely competitive with existing USGI aluminum magazines.

Features and Improvements

The GEN M3 PMAG is fully compatible and tested with all currently fielded AR-Pattern rifles including the M16, M4, Mk18, SPR/Mk12 variants, and other rifles of this lower receiver geometry, as well as weapons featuring the SA-80/HK416/IAR magazine well, and the M249 SAW. All platforms are tested unsuppressed and suppressed.

The GEN M3 PMAG features a slimmer profile and floor plate design than previous generations of PMAG, with improved texture for a positive grip under wet, muddy, cold, or other adverse conditions, and a paint pen dot matrix for easy marking and tracking. This slimmer profile fits better in magazine pouches for greater usability.

The GEN M3 PMAG Features an over-travel insertion stop, which prevents over-insertion of the magazine under stress or vigorous open-bolt reloads, as well as providing an extra measure of durability for weapon functionality after loaded weapon drops or when using the magazine as a monopod.

The GEN M3 PMAG features a four-way anti tilt follower with generous dust and grit clearances for performance in adverse conditions, and water drain features for over-the-beach performance.

The new material, manufacturing, and design create a reinforced mag catch area, tested to thousands of removal and insertion cycles for positive magazine retention. It is quite literally possible to hang from a PMAG inserted into a magazine well with no negative effects or failure.

The MagLevel Window System provides visual indication of remaining rounds in the magazine, and is visible under NVD aid in darkness. Unlike translucent or transparent magazine designs which cease giving useful information after the follower enters the magazine well, the MagLevel system provides round count at a glance down to the last remaining round.

The GEN M3 PMAG is currently shipped in Black and Sand for better IR significance performance without paint.

The GEN M3 PMAG is easily disassembled for end user cleaning and maintenance, and is specifically designed to be impossible to reassemble incorrectly.

The GEN M3 PMAG is currently available in standard, 30 round capacity with and without MagLevel Windows, as well as 10, 20, and 40 round capacities. All stated capacities are true capacities…there is no need to download magazines for reliability concerns or ease of closed-bolt insertion.

Thanks for the compliment.

For the 1970s the SteyrAUG system as a whole was generations ahead of it's time.

That said the magazines (while advanced) were not without issues. The material was very susceptible to chemicals and round retention under ambient temperatures was marginal at best (in high temperatures rounds would self unload in a rather dramatic fashion).

That said the AUG magazine is still rocking 30 years later while the Ramline magazines were junk the day they were released (10 years after the AUG).

Words, mean things.

The text posted provides an insight into the design requirements behind the most utilized polymer magazine in US combat history (outnumbering all others, combined). It includes very specific information regarding durability in terms of impact strength vs tensile strength relating to the primary mission of the rifle magazine (as an ammunition feeding device).

"Education is the best form of Marketing" (Magpul Foundations) so in that aspect education IS a primary form of advertising for us, that said what you do with the knowledge we share is up to you. You can learn from the post, address the points made specifically or you can choose to ignore them.

Sorry to lose you as a customer. That said we defend our intellectual property (ip) as we do our personal property and expect no less from anyone else.

Intellectual property rights were so important to our founding fathers that they ensured it was in the text of the US Constitution itself...


The concept of no individual intellectual property is a primary Communist ideal.

Many like this type of design and my advice is try everything and keep what suits your mission best. We just have a different design philosophy than this born out by our testing.

During the M3 development program we experimented extensively with many different materials and concepts. This included metal secondary support structures. For us the negatives of this approach far our weighted the positives in both manufacturing and real world usage.

No one called him a communist but he is promoting the concept that defending ones intellectual property is somehow wrong, which IS a longstanding communist fundamental.

Patent law is the law of the land. Expecting individuals and companies to abide by the restrictions of other patents but not defending their own IP is just plain dumb.

It is the Plastic, Processing and Geometry combined.

We are probably one of the most qualified to answer questions regarding translucent magazines, seeing we have tested countless translucent materials since 2007 and even built two translucent production molds.



We have not released any translucent designs as we have yet to find one that meets our level of performance (as outlined in the PMag design philosophies posted earlier)

We have never filed a lawsuit regarding a translucent magazine but we have filed against companies violating our published magazine utility patents (ip.magpul.com). If we do not defend our IP we lose it.

I am careful not to insult anyone personally in a technical forum but I will address specific policy issues directly if they come up. I stand by my statements regarding IP/Patents (Founding Fathers vs Communism) and my view that "Expecting individuals and companies to abide by the restrictions of other patents but not defending their own IP is just plain dumb".

NOTE: Patent Law is a Federal law and as such is by definition "the law of the land" (not sure how the CO state law comes into it).

Yes it does get tiring for us (thanks for noticing) but it is a reflection of our commitment to education.

In summary, the polymer used in your referenced magazine (and many others) will deform or bend under impact rather than crack. This material sacrifices higher tensile strength (rigidness) for more impact strength.

In the case of your preferred magazine design, they compensate for lack of tensile strength material in the feedlips by adding a secondary metal support structure to reinforce that area. This concept is based upon their own design philosophies which we understand, but do not embrace based on our own testing. Other manufactures use slightly harder material to achieve enough tensile strength to maintain round retention in the feed lip area but also soft enough that the material as a whole can still resist hard impacts by deforming/bending to absorb energy.

As explained in the Magazine Design Philosophies posted on page 1, we choose not reduce high tensile strength to make the body softer to absorb impacts better (as we believe it adversely effects reliability), we have stated this stated many times before...

"It is our view that PMag reliability comes from specific geometry that is consistently maintained by high "tensile" strength material."

This concept has been combat proven in 8 years of the GWOT and while the PMag will constantly increase in impact strength (through advancement in polymers) the high tensile strength will be maintained in the design.

Again all this information is contained in the Magazine Design Philosophies we posted on page one.

By your logic then a solid piece of plastic would make the "best" magazine as it could not be broken. The majority of internet testing (including your references) involves very little (if any) controlled live fire testing. We address this misconception of the primary mission of a magazine in the PMag design philosophies posted on page one of this thread.

As for live fire testing under combat conditions I will just point to the 8 years of the most intense small arms combat this country has seen in 30 years.

For overseas combat deployment, one magazine was voluntary chosen by combat deployed troops more than all others combined for the entire 8 years of the GWOT. The PMag.

What about the most high profile mission during the GWOT? What magazine was chosen above all others to go on the mission. Answer again is the PMag (in the form of the the EMag- Euro version of the PMag).

For you this evidence might not be as conclusive as your cited testing, but we are content with the results.

Cracked PMags have become much rarer due to major strength improvements from material and processing changes over the last 8 years of PMag manufacturing. Even a cracked PMag will continue to function (even full auto) if used. I have never heard of identifiable pieces of PMags being littered on any range in the almost decade the PMag has been in service.

For examples on how much abuse a current PMag M3 can without damage compared to a current issue USGI magazine (with high speed video and live fire full auto testing) see the PMag M3 vs USGI testing videos

This thread has become borderline amusing, as do most threads where Magpul posts their "education" "philosophies". Wonder why people hark on the durability of the magazine so much? Because there are several magazines on the market now for the M16/M4 platform that feed extremely reliably. We have good USGI mags with a no tilt follower, we have Pmags, we have Lancer mags, our mags, Tango down mags...

The Pmag is not the only magazine that will reliably feed the weapon. So what next? What is the second most important characteristic of these magazines besides feeding ammo? We think it's durability, and apparently, so do a lot of other people. I find it funny how Magpul has always picked on USGI mags for not being nearly as tough as the Pmag (which is true), yet when their mags get picked on for the same thing, they try their best to downplay the importance of the magazine toughness almost to a point of insulting people who find it important.

Bottom line, there are a few good choices for good feeding magazines for this platform. There are even a couple of good choices that feed AND are almost impossible to break. This isn't rocket science as far as logic goes....