Jungle Insurgency: The Arms of ISIS East Asia (Part 1)

The Islamic State in East Asia (ISEA) is a branch of ISIS that is unique in many ways, from its weaponry and location of operations, to its membership. ISEA is active in the Philippines and other countries in South East Asia (such as Indonesia), but in this article I will be focusing on the arms of ISEA militants in the Philippines.

This group has been engaged in armed assaults against Filipino authorities for close to 3 decades as part of jihadist movements that were a precursor to ISEA--specifically movements like Abu Sayyaf and the Maute Group. Many reports regarding ISEA continue to use the old terminology when naming who was responsible for attacks, but essentially these groups are now operationally indistinguishable. Many have made "Bay'ah" (an oath of allegiance) to ISIS proper in the Middle East- this is why ISEA operations are now broadcasted by ISIS media networks, such as Amaq. However, multiple factions remain loyal to Al Qaeda.

Whilst the ISEA Bay'ah was made to ISIS and their leader al-Baghdadi at separate dates across 2014 and 2015 by disparate groups, this transition to Islamic State allegiance made significant progress around October 2015. At that point, representatives from multiple jihadi organisations in the Philippines (That have links to Malaysia, Indonesia, and other countries), released a joint video announcing that they were uniting under the leadership of the now Southeast Asia "Emir" Isnilon Hapilon.

The Maute Group may not have been included in this gathering, but by April 2016 were clearly aligned with ISIS in their publicly released propaganda. They also pledged loyalty in April 2015, along with Ansar Al-Khilafah Philippines- another Filipino Extremist Organisation. (Although this faction later split and is not formerly loyal to ISIS) It doesn't appear that an official ISIS Wilayah (Translatable to a new province of ISIS) was ever proclaimed until July 2018. ISIS central propaganda organisations continued to report on the Philippines under the title of “East Asia”up until that date. However, the militants themselves seem to have taken to the practice of issuing statements and media in the name of "Wilayah East Asia" often, even prior to the official declaration.

Whilst Abu Sayyaf, the Maute Group, and other organisations (Or factions of groups)--such as Ansar Khalifa Philippines and factions of Bangsamoro Islamic Freedom Fighters--have all sworn allegiance to ISIS, and are now publicly identified with the black flag, it appears that command and supply structures of the groups could remain somewhat aligned with the previous organisations, as expected. These groups that make up ISEA are certainly united and collaborate (for example in the capture and battle for the City of Marawi), but there continues to be a certain level of independence in operations and attacks. This is likely down to the historical geography of the groups' influence and control in the area. Links and competition between IS and al-Qaeda linked groups remain vague.

Regardless, each Group can now be regarded as an official affiliate of ISIS proper, even if the precise terminology isn't always used by media organisations or the jihadist groups themselves. ISEA lacks significant territorial control. It is limited to insurgency style attacks in larger cities in the Philippines--especially those not in majority-Muslim areas of the country. The group does retain significant arms and operational freedom in the remote Jungle areas though, and around the islands such as Sulu.

Recent Social Media activity from Individual fighters seems to show that Filipino Government action (supported by American and Australian forces, plus various other alliances) is somewhat successful in curtailing the operational ability of ISEA, especially since the Battle of Marawi, in which hundreds of fighters were killed along with multiple top leadership figures.

The group's ability to retain permanent bases is limited, and it faces frequent raids against their often ramshackle encampments in the jungle. This does not prevent an active transfer of funds and personnel from the Middle East to East Asia however, as was seen in particular with the Battle of Marawi, where large quantities of US Dollars were sent from ISIS central in the Middle East to significantly bankroll the organisation in South East Asia.

Who the current official Wali of ISEA is (Or even if one exists) is quite difficult to discern. Isnilon Hapilon was killed during the Battle for Marawi, and it appears that the leadership figures of groups that make up ISEA change often. This is a consequence of Filipino authorities effectively clamping down on the jihadists. Foreign membership of ISEA is a contentious subject, as local authorities often seek to deny non-local fighters presence and ISEA media, official and unofficial, are extremely careful in revealing the presence of foreign fighters. Regardless, it appears clear that there has been at least double figures of militants that have either made Hijra- in this sense, to migrate to strengthen the Islamic State (as encouraged by ISIS in their "Inside the Caliphate" propaganda), or have transferred from ISIS central to facilitate and improve the capability of the group in the Philippines. There also appears to be a number of fighters that travelled previously to Iraq or Syria to fight for ISIS and came back to the Philippines. It appears that sometimes the main indication that a foreign fighter was involved in an ISEA action is only after their death, as was the case with a Moroccan Individual involved in a VBIED attack.

There is no reason to doubt continuing interaction between ISEA and ISIS central. For now it is perhaps curtailed by the territorial defeat of ISIS in Syria, but it does appear that activity in other areas of Syria and Iraq are again rising, and that media operations appear substantially intact.

In fact, as ISIS in their traditional centre of operations is suppressed or forced underground, other provinces of the group, such as in East Asia or West Africa, are both becoming more significant in terms of practical freedom of operations and media releases (Although ISEA has not recently released long-form videos such as those from West Africa or Iraq, likely because the organisation is still rebuilding strength and funds after the Marawi battle, which while a huge propaganda success, did lead to the decimation of various important figures within the group).

ISEA does remain active in recent years, with a January 27th 2019 double suicide bombing in the Cathedral of Our Lady of Mount Carmel in Jolo in which 21 worshippers died, and a large gun battle on Saturday 2nd February not far away, where over 100 militants are said to have gathered and engaged in a fierce clash with the AFP (Armed Forces of the Philippines) before retreating back into the Jungle of the Patikul Mountains. This encounter left 5 Soldiers dead and 18 wounded, with only 3 Militants claimed to be killed. If local media reports of ISEA numbers are correct, a gathering of this size is both rare and indicative of the growing confidence and ability of the group. The group has engaged in small-scale battles with militia forces in October 2019, and an attempted double suicide bombing using two Egyptian fighters was foiled in early November 2019, also in Jolo. Images of Fighters in Basilan, Mindanao and Jolo were published in November 2019 also, showing healthy numbers of militants pledging bayah to the new "Caliph" of ISIS, Abu Ibrahim al-Hashimi al-Qurashi, after his successor was killed in a US raid on October 26th.

However, ISEA has been relatively quiet compared to to other branches of ISIS throughout 2019 and 2020, indicating an enduring weakness and need of rebuilding since the battle of Marawi. Despite the drop in action since the battle of Marawi, ISEA is a branch of ISIS that continues to plague South East Asia and the Philippines, and has a unique and long history, with disparate local insurgencies becoming united under the banner and control of ISIS. Whilst the insurgency has been under sustained pressure, the group retains the ability to cause casualties and to capture weapons.

ISEA does not appear to be fading away soon, and is a relatively unique example of where imagery released via individual social media accounts by far outweighs official video and pictures, such as those released by Amaq, or via any number of regional or central ISIS agencies. (October 2019 video from Amaq Agency of ISEA action against Government-aligned militias appeared on unofficial channels at least a week prior to it's release by Amaq) This means that insight into arms is both more representative of actual use (As opposed to being filtered through sanctioned and sanitised channels), but also typically of lower quality and with less visual detail available. However, the unfiltered nature does give us an excellent "actual" viewpoint, especially combined with official media and those from authorities.

Their weapons are a very interesting snapshot into the supply chains and preferences of the insurgents- let's take a look.

Contents of Part 1:

• Standard Issue Arms
• Unusual and Uncommon Rifles
• Precision & Long Range Platforms
• Light, Medium, & Heavy Machine Guns

Standard Issue Rifles

ISEA is possibly one of the only branches of ISIS, excepting perhaps elements of ISIS forces in Iraq, to have standardised their small arms on NATO standard calibres. This is likely due to these rounds being used by the Armed Forces of the Philippines- in particular 7.62x51mm and 5.56x45mm. Both of these calibres are used by multiple militaries across the world, both within NATO and outside of it.

As the Arms of ISEA are mainly those that are used by Armed Forces in the region, in particular those of the Philippines, this is no surprise. In a similar fashion, the arms themselves are also broadly representative of those in use by the AFP, with a large quantity of additions.

The most common rifle, seen in the bulk of images posted by members of the group, is the M16A1.  

This rifle is emblemetic of US Power worldwide, in particular of the War in Vietnam, where reports of the platform being either a wonder weapon or an absolutely unreliable death trap were both inaccurate. Whilst the M16A1 is long superseded in the United States' military service, this rifle continues in use across multiple countries, having either been sold, given as aid, or locally produced.

In the case of the Philippines, a traditionally close military relationship with the United States exists, which included multiple deliveries of rifles, as well as licensed production in the Philippines. These rifles are designated the 613P (P standing for Philippines), and 653P, variants of the Colt 603 rifle and Colt 653 M16 carbine respectively.

Filipino M16s were produced from 1974-1986, and the ~150,000 rifles produced (Although precise numbers produced for each type is unclear) during this period continue to serve with the Armed Forces of the Philippines, and also in Militant service, whether captured or diverted. There were also very large quantities of US-made M16 and M16A1 delivered during the late Vietnam Era; the US Government's Foreign Military Sales program delivered around 4,000 M16A1 (Colt Model 603) before 1975, whilst another program, the Mutual Assistance Program, under the auspices of the Mutual Defense Assistance Act, delivered 22,991 rifles in 1975. This wasn't all- around 45,000 Model 613 (Export version of the Colt 603) rifles were acquired directly from Colt before 1976. The last shipment of 30,000 M16A1 rifles was delivered during the Presidency of Gloria Arroyo, between 2001 and 2010, directly from US Surplus stocks. The sheer number of rifles produced or delivered to the Philippines goes some way to explain the proliferation of these rifles amongst ISEA. However, the small quantities of M16A2 also delivered by the US at that time have not appeared with ISEA.

It is is almost impossible to determine whether a rifle is a Filipino-produced rifle or a Colt rifle produced in the United States, as there is no difference at all between the rifles apart from factory markings. These are typically difficult to discern.

Various upgrades and updates to these tired rifles have been carried out or proposed by the the Filipino Department of National Defense's Government Arsenal (GA), but it appears that a high percentage of these rifles have remained close to stock in AFP usage. The extent of modernisation appears to typically be replacement handguards (usually M16A2-style), and occasional stock/barrel replacement. This has, of course, filtered down to the rifles seen in use by ISEA, with sub-groups who are typically better funded or experienced generally using M16s in superior condition.

There is evidence of upgrades and changes to these rifles that are specific to the militant groups, and not carried out by authorities. This includes third-party replacement stocks, pistol grips, optics, and camouflage jobs, as can be seen above. It is often unclear whether weapon upgrades and customisation were carried out by Authorities or by the militants, but amongst some fighters it appears that third party quad rails are popular. These appear to have been purchased from abroad, or sourced in the country- the Philippines has a thriving domestic firearm culture. A few rifles appear to have been cut down, in a similar fashion to the Menusar carbines of the Israeli Defence Force.

News reports on Islamist insurgencies in the Philippines indicate that the M16 has been the weapon of choice for such fighters for many years- It's possible that weapon selection is heavily influenced by availability also, as the area is awash with M16 variants.

Following M16 pattern rifles, one of the most prevalent rifle types in use by ISEA is the M14 Battle Rifle. The M14 is an improved select-fire variant of the WW2-era M1 Garand, rechambered to the 7.62x51mm round and utilising a 20 round magazine. This full size rifle round is considerably larger than 5.56x45mm, and therefore carries with it the associated properties of being more effective at range, typically causing greater damage to flesh/body tissue beyond 125m, and being much more effective against structures and cover. It is however much heavier, has much greater recoil, and is generally regarded as being much harder to control when firing in fully automatic.

The M14 is the direct predecessor to the M16, being the standard service rifle of the US Military from 1961 to 1964. This period was an exceptionally short service rifle lifetime, but nonetheless around 1.3 million M14s were produced, and hundreds of thousands of these rifles were sold or donated to US Allies around the world, including the Philippines, which received around 104,000 of them. The rifle is still in service with the AFP, with Filipino Marines being pictured with M14 throughout 2017 and 2018, including in Marawi and other anti counter-terrorism operations.

These rifles have made their way into the hands of ISEA militants in multiple different areas of the Philippines, and are wielded by a large majority of fighters. Similarly to the M16, the M14 is sometimes customised with paint jobs and optics, although they are usually close to stock configuration. They have also been spotted with new synthetic chassis, often with a folding stock. This would greatly assist in the size of the M14 for transportation across the jungle.

The chassis above appears to be a synthetic model, complete with Galil-style folding stock. Manufacturer is unclear. It also appears that craft-adapted stocks have seen use, with a side-folding stock strongly resembling that of Galil or Bulgarian AK rifles being attached to a wooden stock.

Whilst not entirely clear, it appears that in general militants prefer the 5.56mm platform as well as enjoying a greater supply of rifles and ammunition of that type. For the average IS fighter, who typically appears to be both of a young age and of a slight build, the M16 platform would be comfortable to wield and effective. The platform is light, inexpensive, reliable (With maintenance), and enjoys excellent commonality of parts with civilian AR-15 parts and accessories, easing supply chain and upkeep difficulties as opposed to rarer platforms, such as the M14.

While the M14 is an older weapons system compared to the M16, and certainly is likely to present a greater ergonomic and maintenance challenge to the group, the hard-hitting power of the 7.62x51 round may be useful for longer range operations as compared to the group's 5.56mm platforms. The group seems to have no shortage of either, and as the AFP continues to actively use the M14 against militants, it seems that the group may well continue capturing well maintained rifles from government troops, ensuring a fresh supply of whole rifles or parts.

The rifle is also be used in the DMR role. This requires optics and trained users. The group has certainly attempted to provide the former for use in a counter-sniper role against the AFP, as I will detail further below in my "Precision & Long Range Platforms" section.

Another common rifle used by ISEA is the Galil, in both it's older variants and the new ACE version. The IMI Galil is closely based on the Finnish Valmet Rk. 62 rifle, which in itself is based on the AK-47. Whilst the Rk. 62 is broadly highly similar to the milled AK series, differing mainly in stock, sights and handguards, the Galil is a variation of that design itself, including further changes to handguard, stock, and most importantly a change in calibre to 5.56x45mm NATO, as opposed to the 7.62x39mm Rk 62. Both may be considered very high quality variants of the AK series.

The Galil was produced in a number of variants- the AR (Standard rifle variant), ARM (Automatic Rifle Machine-gun), and SAR (Shortened version), but the ARM was the most widely produced. The ARM is also the most commonly seen in use by ISEA.

This Kalashnikov-based platform uses its own pattern of magazine (Typically with 35 round capacity), which is not compatible with M16-based rifles of ISEA. Whilst the slightly-larger capacity of these magazines could an asset to ISEA fighters, the relative scarcity of these magazines and incompatibility with other platforms means that this rifle is likely to be of slightly limited utility to the group. However, the Galil is highly reliable and easy to maintain.

It appears that the Galil is sometimes carried by mid-level leadership figures, as a mark of prestige. It does not appear that magazines are scarce enough that the Galil cannot be utilised, merely that it cannot be widely fielded. It also can be spotted with the M203 40x46mm grenade mounted, which requires modification to the the rifle (Removal of handguards, bipod etc). This modification of the Rifle and UGL to be compatible is seemingly distinctive, with professional militaries across the world very rarely doing so.

A newer iteration of the Galil, the Galil ACE 21, can also be spotted in the hands of ISEA. This weapon is very similar to previous Galil versions, but includes much more modern features, such as accessory rail, M4-style collapsing stock, improved accuracy and more.

The Galil ACE 21 is widely used in the area, including by the Philippine National Police, who use it (Amongst other arms) as standard issue. The images above also have the appearance of being capture from Police forces following an attack, although corruption is also a possibility. The small size of the ACE 21 and it's ammunition compatibility with the rest of ISEA's arms would make it a useful short-range weapon, which is also significantly more modern than many of the group's weapons. However, it lacks the ability to mount the M203 UGL.

Whilst the ACE is a fairly modern AK variant, evidence exists of other AKs being in use by ISEA, including multiple Type 56 rifles. These are not used by the Philippines, and are generally regarded as having been smuggled from neighbouring states. These are accompanied by a few AKM-pattern rifles- whilst a shipment of 5000 AKMs was sent to the Philippines by Russia in what was largely a symbolic effort, these appear to have been little used and images of AKM rifles, rare as they are, pre-date the supply.

Another weapon type used by ISEA is M4-type carbines. This includes a variety of arms from different manufacturers (For example, small quantities of Colt M4 variants were gifted by the United States in 2017), but most typical is the Remington R4A3. This is most clearly described as a copy of the Colt M4 Carbine, originally intended for supply to the US army. Whilst this was stopped by legal action from Colt in 2012, Remington went on to market the rifles for export. They have no practical differences in design to the original issue M4, but the rail system and a few other details differ slightly.

Whilst it is difficult to determine specific sourcing for individual R4s used by ISEA, they are extremely likely to be part of a November 2013 contract for the supply of "over 40,000" rifles to the Philippine Army and Philippine Marine Corps, an order that was largely complete by the beginning of 2016, with a total of 56,843 being delivered from Remington. Whilst the stated intention of the purchase of the carbines was to replace the M16 series in use by the AFP, this has also meant that the R4 has fallen into the hands of ISEA, usually via capture from AFP troops.

This is a modern, lightweight, and effective platform and hence is given to leadership figures when captured- for example, Isnilon Hapilon and Omar Maute, leadership figures of Abu Sayyaf and Maute group respectively, were killed carrying R4 rifles in October 2017 during the final stages of operations to remove ISEA from Marawi. This indicates that the group possessed R4 rifles at least prior to the seige of Marawi, when for a period ISEA gathered large quantities of modern arms and ammunition for the attack on the city. This was merely 12-16 months after the last R4s arrived from Remington, although deliveries started in 2014.

The R4A3 barrel's 1-in-7 twist rate also enables it to use armour-piercing M855 Ammunition. Whilst M193 ammunition still appears to be standard issue for the AFP, reporting suggests that a change to the famously-known "green tip" ammunition may have started in 2016. Whilst the M855 is usable in the M16A1 rifles of ISEA, the 1-in-12 twist rate of those rifles means that accuracy beyond 100m would greatly suffer. Hence the use of the R4 is both a status symbol and a practical requirement for ISEA rifles to be of use at longer ranges with recently captured ammunition, although M193 ammunition is also likely to be extremely common both in militant stockpiles and among government troops or police.

An extremely common accessory for rifles in use by ISEA is the M203 40x46mm Underbarrel Grenade Launcher. The M203 is a very widely fielded weapon since 1969, seeing use in almost every conflict involving the US Military or it's allies, from Vietnam to the Falklands War, to Syria today. A very versatile weapon, the M203 and its variants or clones has been attached to almost any rife platform, from the M16 Series, to the Israeli Tavor.

In normal US Army or Marine Corps usage, the M203 is not usually standard issue on every rifle used in the typical squad, often appearing appearing on only a single rifle per 4-5 man fire team, although this practice does vary between services. This differs to the usage by ISEA and it's component groups. Instead, it appears to be standard practice to attach the M203, if available, to every rifle possible.

There appears to be an abundance of M203 and 40mm ammunition available, typically standard High Explosive rounds. In fact, depending on location, open source images I have viewed indicate that it is not uncommon for more rifles to be equipped with the M203 40x46mm Underbarrel Grenade Launcher than those without, except for M14 rifles, which are never seen with M203.

Interestingly, on occasion when carbines such as the Colt 653P are used that lack the "M203 cutout"- the mounting spot for the M203 on the barrel- the group seems to have often solved the issue by fabricating a ventilated barrel shroud to keep the M203 in place and attached, as well as sometimes fabricating custom mounting solutions for rifles such as the Galil and FN CAL. This indicates the M203 is of high value enough for fighters to commit time and resources to adapt it to rifles that it wasn't designed for. It appears that if available, the original M203 barrel shroud along with leaf sight is employed, but often none is used. This curtails the accurate use of M203, but experienced fighters, in particular at closer ranges such as in towns or the jungle, would still be able to employ the grenade launchers. Typically, it appears that 30-50% of rifles in use have M203 attached, with some groups of fighters (Typically 4-10 individuals) entirely equipped with M203, even if no grenade ammunition is carried on their person.

This use of the M203 as a force multiplier exceeds that of the AFP, and could concievably be extremely useful for the militants in fighting their numerically superior opponents, able to inflict damage at multiple ranges with only a limited number of attackers.

It's not uncommon for fighters, as can be seen in images above, to carry between 4 and 12 40x16mm grenades on their person, suggesting that ISEA places great emphasis on the use of large quantities of 40mm grenade fire to amplify their ability to cause damage and casualties to government forces.

Combat images, such those from Marawi, typically show smaller quantities of grenades per fighter compared to social media- it's likely the latter images may be somewhat exaggerated for the sake of appearances. Regardless of this, in particular in areas where the group has greater funding and success, ISEA does not have any scarcity of new/good condition 40x46mm rounds whatsoever. This is so much so that images posted online show brand-new rounds being converted into use as hand-thrown improvised grenades. Though it is feasible that this action is due to a lack of launching platforms, there may be a considerable oversupply of rounds in some areas, either via Ghanimah (Islamic term for captured war booty) or corruption. It may also be a lack of competent or trained users of the M203, even if large quantities of rifles show it attached.

Battlefield capture images do show large numbers being captured, but successful engagements with the AFP, whilst rising in recent months, are still low.

It is difficult to determine the source of these rounds and launchers, as the M203 and it's ammunition has been manufactured both locally and in other spots across the globe, in particular of course the United States. It appears that the bulk of M203 are well used but maintained well, suggesting a long term supply chain of launchers and rounds from military arsenals in the region, as well as deep familiarity with the platform. Most appear to be older M203 models that are hard to trace timing and precise origin, but are most likely to be supplied from US stocks during the deep relations between the countries that continue to this day- it's very likely numbers of M203 were supplied along with M16 rifles.

However, some newer launchers, mostly those that are attached to Remington R4 carbines, are from Airtronic USA. Airtronic USA is one of primary manufacturers of M203 in the United States, supplying both the US Army and foreign clients.

Under the US Government Foreign Military Sales programme, 2,865 M203 manufactured by Airtronic USA were delivered to the AFP over 2017-2018 in two phases: phase 1 was for 2,200 units of M203 grenade launchers, while Phase 2 was for 684 units. These grenade launchers were reportedly directly intended to be installed on the Remington R4 platform, and many could be seen in use during the seige of Marawi city by government forces.

They have also fallen into the hands of ISEA, although in much lower quantities than the Vietnam-era M203 most commonly found. However, the M203 is a fairly simple launcher and if maintained all should be functioning for long periods.

Unusual and Uncommon Rifles

ISEA makes use of a considerable variety of "non standard" rifles as well as those that are AR-15 pattern. The sourcing for these rifles is difficult to verify but they are an excellent demonstration of just what kind of platforms are available locally.

Precision & Long Range Platforms

It appears that at least some militants have adopted a practice seen all over the world- that of the M16 as an impromptu Designated Marksman Rifle. As the M16A1 with it's 20" barrel is inherently more accurate than many weapons used by insurgents, such as the AK series, as well as the 5.56x45mm round's reasonable mid-range performance, multiple groups around the world have adopted M16 rifles as a solution to a lack of dedicated DMR platforms. This is particularly useful when operating in urban environments, such as encountered by ISEA in Marawi, or even close in environments, such as the the jungle, where the deficiencies of the smaller cartridge are not as apparent as when operating at range, where 7.62x51mm and larger is generally regarded as superior. In Urban environments, however, 5.56mm platforms are perfectly acceptable to target security forces.

Equipped with a medium range scope, the M16 (And occasionally it's Chinese clone, the CQ) are competent rifles in the improvised DMR role. In fact, this concept was taken up and extended by products such as the Mark 12 Mod 0/1 Special Purpose Rifle, used by US Special Forces. Another example, much closer to ISEA, is the Marine Scout Sniper Rifle (MSSR) of the Philippine Marine Corps Scout Snipers, which is an evolving programme of improvements on the basic M16A1 design (Using original M16A1 lower receivers), to create what is said to be a very well performing rifle up to 600m.

Individual militants can be seen with medium range scopes attached to original M16 rifles, sometimes with replacement upper receivers. There is also limited evidence (As can be seen above) that ISEA have also captured at least one original MSSR, although it isn't clear if precision 5.56mm ammunition was also captured, which offers much superior performance compared to SS109/M855 ball ammunition.

The M14 mentioned above has also been used as a designated marksman rifle, likely because of the superior performance of the round at longer ranges compared to 5.56mm. Again, it's unclear if ISEA has gained access to marksman ammunition for the M14, but available evidence indicates that it's unlikely.

Above can be observed two M14 rifles in the sniper role, although as stated previously, it's use case is likely to be closer to a designated marksman rifle. The scope mount on the second image appears to be identical to a CYMA/Matrix Airsoft scope mount, which is itself an altered copy of a Springfield Armoury scope mount for the civilian M1A rifle.

It's unclear how effective the airsoft scope mount will be with the real rifle, but it can be expected that the lesser quality and tolerances of the the airsoft mount will effect the ability of the scope to "hold zero"(Not requiring frequent adjustment in order to hit a target at a particular range with acceptable accuracy), and also will have greater likelyhood of breaking or falling apart. However, it would be essentially functional.

The fighters of ISEA and it's subgroups have also used limited amounts of bolt-action rifles. These range from typical hunting rifles, easily available in the area, to very uncommon M24 SWS rifles- the well known US army adaption of the Remington 700 platform to military use. This rifle is also in use with the Army and Marine Corps of the Philippines.

Light, Medium, & Heavy Machine Guns

Whilst the Islamic State in the Philipines is well armed with a variety of Cold War and Modern small arms for the individual fighter, the group has displayed a much smaller variety of machine guns. However, they do exist in reasonable quantities, with the average ISEA squad usually appearing to carry at least one machine gun, typically the 7.62x51mm M60 GPMG.  

M60 in ISEA hands appear to be primarily sourced from Armed Forces of the Philippines, either via corruption or capture, just like the M16s carried by ISEA. The M60E3 is the primary general purpose machine gun of the AFP, although it does possess some weapons upgraded to M60E4 standard. It appears that M60 has been supplied in large quantities to the AFP by the United States.

Although the M60 GPMG carried by ISEA are likely of 1960s-1980s vintage, and usually display high levels of wear, it appears that the group has long experience with the M60 and can operate and maintain the platform. The M60 takes the place of the "standard" machine gun that is usually taken up by the PK series of machine guns in the Middle East.

The Browning M1919 medium machine gun also features in the arsenal of ISEA. The .30-06 M1919 has been regulated to second-line and static use by the AFP, and is also rarely seen in use by ISEA, who appear to have limited access to the platform.

Whilst the M1919 is an older (WW2-Era) platform, with maintainence and a supply of .30-06 ammunition it would be perfectly servicable for ISEA fighters. Given the platforms's age and apparent lack of ammunition, it seems that it is used only rarely. It appears that the AFP GA (Government Arsenal) does not manufacture the ammunition required, unlike 5.56x45/7.62x51, and as a result only existing stocks of ammunition can be used up by the AFP, and by extension IS EA. However, M1919 may be used in greater quantities by government-aligned militias, who often use older/second-line equipment in larger amounts. (This also applies to the M1 Garand, which is chambered in .30-06 too and can also be found across the Philippines)

During the battle of Marawi, an M1919 could be spotted being wildly fired from the hip at AFP forces- it is difficult to imagine a scenario further from what the venerable machine gun was designed to do almost 100 years prior.

A close cousin of the M1919 is the .50 calibre M2HB heavy machine gun (Commonly known as the Browning .50 cal), which seen use by ISEA in limited quantities. However, it's employment is notable for it's rarity and very clear use case- the M2HB has essentially only ever appeared in significant numbers during the takeover of Marawi by ISEA, in which the HMG was used as the weapon component of ISIS Technicals (Pickup trucks), and during the intense urban fighting, both against personnel and aircraft.

The M2HB is extremely expensive on the black market, and offers an ability analoguous to the DShK 12.7x108mm HMG used so often by ISIS in the middle east. As part of the ISEA military buildup for the takeover of Marawi, it appears that the M2HB was procured in hitherto unseen quantities, along with plenty of new ammunition, presumably over extended periods of time. These were then mounted to vehicles. It appears that at least one AN/M2 (Fast-firing aircraft variant) HMG were also used by ISEA.

This would give the militants a long range and heavy hitting capability, one which is very useful in the swift style of fighting that ISEA attempted to emulate from the Middle East- the technical being a key part of that strategy. It is difficult to determine how many M2HB-equipped technicals were employed, but between 10-20 appears realistic, acompanied by larger quantites of M2HB dismounted from any vehicle. Quantities of M2HB were eventually recovered by AFP forces when the city was retaken.

Subsequent to the seige,  the Philippines military made a deliberate effort to reduce the threat of  .50cal weaponry. Started in late 2017, this multi-pronged approach involves: "premium pricing for M2s in buy-back programs, better security of M2s and 50BMG ammunition at military bases, and efforts by the Philippines navy  and customs to choke off black market importation". It would appear that the ability of ISEA-affiliated groups to obtain HMG and 12.7x99/.50BMG ammunition was clearly of enough concern to take decisive action. The M2HB does not appear to been used by ISEA since the battle of Marawi, but the group may retain a limited number stockpiled, or may have managed to purchase additional units.

ISEA has a varied and very interesting mix of weapons, as a result of the particular location of the group, and the long standing weapons flows in the areas in which it operates. Stay tuned for Part 2, which will include:

RPGs, Standalone Grenade Launchers, Recoilless Rifles & IEDs

Handguns

Ammo Sourcing

Foreign Sourced Weapons

Note: This article represents about 50% of a research and writing effort from early 2019-2021, and was very time consuming. If you enjoyed this Article, Please consider putting a few dollars, pounds or your local currency in my direction via ko-fi.com/CalibreObscura

This project would have been much harder without the assistance of @flava13_v7, who now sadly appears to be offline. Many unofficial images were gathered via his channels. My thanks also goes to Paweł Wójcik, who's work has been very helpful.