The M1919A5, Fixed, Caliber .30 air cooled Browning
machine gun, Major Item 51-114, was a special purpose design that was
intended to replace
the M1919A4 Fixed model in certain armored vehicle applications.
In the late 1930's and early 1940's the U.S. Army's
concept of armored warfare was not well aligned with reality.
Most U.S. armored tactics had evolved based on the
limited experience gained in WWI along with some theorizing about the use of
armored forces in the screening, scouting and raiding traditions of the Cavalry.
Light tanks like the various models of M2 and M3
Stewart with their 37mm main gun were to be employed as scouts and infantry
Medium tanks like the M4 Sherman with
its 75mm and later 76mm main gun were intended to be used as Infantry support.
To counter enemy armor "Tank Destroyer" units which
mounted various weapons up to 90 mm on tracked vehicles were supposed to be the answer.
The big problem with this concept was that the
German armored doctrine was not based on the U.S. theory of how they
were supposed to operate.
Light tanks while fast, were just too lightly armed
and armored to be effective and the medium tanks were not designed to go toe
to toe with German armor that accompanied either mechanized (Panzer) or
conventional infantry units.
Contrary to popular opinion about so called
"Blitzkrieg" warfare the WWII German ground
forces were only about 50% mechanized, many conventional infantry divisions
made extensive use of draft animals.
By contrast U.S. forces used few draft animals
except for unusual circumstances like mountainous regions of Italy and on
Pacific islands like New Guinea.
The biggest drawback to Tank Destroyer concept was they
were never where you needed them and because they had open top turrets the
crew was vulnerable to air burst artillery.
Eventually they were relegated to roles in the ETO as
self propelled direct fire artillery used for infantry support and capable
of engaging enemy armor if it happened to appear.
After 1943 the entire Tank Destroyer concept was
scrapped and units still undergoing training in the U.S. were converted to
Amphibious Tractor Battalions and mostly used for island invasions in the Pacific
In the mid and late 1930's when the M1919A4 design
was being readied for mass production it was decided to produce both a Fixed
and a Flexible model, and separate Major Item numbers were assigned to each
The M1919A4 Fixed model differed from the M1919A4 Flexible in only
one respect, it used a back plate with a vertical buffer tube lacking a
pistol grip that was adapted from the M1919 Browning Aircraft Machine Gun.
For a complete review of back plates please visit
the "Back Plates/Buffers" tab on the Home page.
The M1919A4 Fixed model was installed in the M1,
M2 and M3 tanks and other vehicles requiring a fixed style of mounting.
mount machine guns in several fashions.
Most of us are familiar with with the trainable
exterior mounting next to the hatch on the turret top. It has a nearly
360 degree field of fire and it is useful as an anti-aircraft and
The main drawback is that it requires the operator to be
exposed to enemy fire.
Ball mountings, where the operator, usually
the assistant driver or sometimes another crew member, operates this forward firing
and hand aimed gun protected from enemy fire by the hull armor and the ball mounting.
above is an Ordnance Department photo of the Assistant Drivers position on a
M4 (Sherman) medium tank from wwiivehicles.com. The weapon shown
appears to be a standard M1919A4 Flexible connected to the ball mount with a pin through the tripod mount adaptors.
The rectangular container just below the A4 is the
ammunition tray with the lid closed.
Most tanks also have a coaxial mounting where the
machine gun is attached to a combination mount and is trained and fired by
the gunner using the same training and elevation mechanism and aiming device
as the main gun.
In WWII this aiming device was an optical sight
either a telescope mounted with the main gun tube or a periscope mounted in
the turret roof. The main gun and coaxial machine gun were both bore
sighted, the center of the bore of each weapon was aligned with 0 defection
and 0 elevation marks (cross hairs) on the telescope.
This cut from TM 9-1078 M4A3 Medium Tank (1954)
courtesy of Tom Chial shows the view through the M70F Telescope used to bore
sight and "lay on" (aim) the weapons.
The range graduations, the short vertical dashes and spaces, are 200 yard
increments from 0 (point blank) to 4200 yards.
dashes and spaces left and right are 5 mil increments of deflection.
This telescope is graduated for the 75 mm M61 armor piercing round
as noted at the top of the lens.
This TM has detailed instructions for bore sighting
both weapons in the combination mount to both the M70F telescope and the
The coaxial machine gun on an M4 tank could be fired
manually or remotely by means of a solenoid.
Tank development included gun mount development and
in some instances, especially with the M2A4 and M3A1 Stewart light tanks using the newly
developed gun mounts, the mounts lacked clearance necessary for retracting the bolt or
even mounting the weapon.
At first M1919A4 fixed weapons were modified
to to work on those mounts lacking the required space.
After 3,000 or so weapons were modified Ordnance decided
to make it official by assigning a "Standard" designation to the modified
Some parts and the basic design used to modify the
M1919A4 and to build M1919A5 weapons from scratch were borrowed from the
M1918M1 Browning Aircraft Machine Guns.
These "borrowed" parts included the cocking stud
that replaced the A4 bolt handle, the bar guides, spacers and the plug,
spring and plunger detent system that held the retracting bar in the forward position
The M1919A5 back plate and horizontal buffer system
was a modified version of the M1918M1 back plate and buffer system.
The A4 top cover hold open feature using the spring,
fixed and movable plates was replaced by the "Cover Detent Assembly" mounted on the left side.
This gave additional right side clearance.
The first obvious mention of the M1919A5 are changes
to many of the part drawings common with the M1919A4 that add Major Item
51-114, the M1919A5, to the "Drawing Pertains To" block, the date of these
revisions varies from
5-15-42 to 5-28-42.
This item from Ordnance Committee Meeting minutes
explains why some M1919A5's encountered have a rear sight bracket and
are equipped with front sights and vertical buffers. They started life
as M1919A4 Fixed weapons and were converted before the M1919A5 designation
These 3,000 or so weapons were likely marked M1919A4 until
they went through a rebuilding process.
This is an Ordnance Department photo from wwiivehicles.com
showing what could be be one of the modified M1919A4's referred to in the
OCM Item 17705 mounted on what the photo caption
calls an "M44" combination gun
mount with the 37 mm main gun installed in a M3A1 Stewart light tank
This photo shows the machine gun equipped with the
vertical buffer back plate generally shown used on the M1919A4 Fixed weapon.
As of this writing I have not been able to locate any
documentation for an "M44" mount, but that does not mean it didn't exist.
The lack of right side clearance and the need for the rear operated
bolt handle are obvious. This weapon has no rear sight base making
it either a M1919A4 Fixed with the rear sight base removed conversion or possibly a purpose built A5.
The firing solenoid is visible just below the trigger.
This photo is from SNL A-55 Section 6 dated 9-42, courtesy
of the RIA Museum, Jodie Creen Wesemann, shows a right side view of what appears to be the same
mount shown in the previous picture identified as an "M44", but this mount is positively identified
as an M23.
This is a clear view of the method of mounting the machine
gun and the trigger solenoid along with the vertical buffer back plate which
was usually seen on the M1919A4 Fixed.
The weapon pictured has neither front or rear sight and
the original digital image did not show the rivet hole for the bolt latch
that would be present if this weapon was originally a M1919A4 Fixed.
It should be noted that any of the three styles of fixed
weapon back plates could be used on either the M1919A4 Fixed or the M1919A5
Fixed even though the A4 Fixed is usually pictured with the vertical buffer
style and the A5 Fixed with the horizontal design.
I have not been able to figure out why Ordnance bothered
to attach the "Fixed" identifier to the M1919A5 as it was not furnished in a
Flexible model like the M1919A4.
Seems a bit redundant.
Not all coaxial mounts required the extended bolt
retracting slide and left side cover detent assembly.
This photo from TM 9-7018 M4A3 (Sherman) Medium Tank dated 9-54
courtesy of Tom Chial shows a coaxial mount using a standard M1919A4
Flexible. The weapon is attached to the mount using the front
mount adapter and the T&E bracket.
The two pronged fork just to the rear of the "Locking Pin
Holes" is the support for the ammunition bag holder.
The first reference to the M1919A5 parts we have
encountered is the September, 1943 SNL A-6, likely the parts were mentioned
in the SNL A-6 dated September, 1942, however we have not been able to
locate a copy of that SNL. Both versions would list all of the parts
specific to the A5. However there is no illustrations of the parts
until the issuance of ORD 9 SNL A-6 in April of 1947.
This cut from the 1947 SNL shows all of the casing
parts and the handle assembly usually referred to as the retracting bar or
The caption on this photo dated February 9, 1942 plainly
states that this is a M1919A5. However, this date is only about two
weeks after the OCM Memo establishing the M1919A5 designation.
Here's a close-up of the side plate markings of the weapon
pictured above. Both pictures courtesy of the RIA Museum Jodie Creen
Wesemann show a M1919A5 fabricated from a New England Westinghouse Browning
Aircraft Machine Gun that was likely a VERY early conversion to a M1919A4.
The big question here is, is this weapon a M1919A4
converted for use in tanks as mentioned in the OCM Memo before the
establishment of the M1919A5 designation and RIA just remarked it A5 or is
it a "real" M1919A5?
My money is on the RIA just remarked so as to have an
"example" of the "new" M1919A5 theory.
Unfortunately, the exact model of Aircraft Gun has been
pretty well obliterated, but the picture it gives a good view of the
function of the stop pin and the plunger in the detent cut holding the
retracting handle in the forward position.
The handle assembly had two different styles of "knobs"
the early version had the familiar bell shaped handle
shown in the previous pictures of the "M44" and M23 combination mounts.
When the A4 bolt handle drawing changed to a
straight or rod style handle in February 1943 this "handle", called a knob
in the SNL, changed with it.
When the M1919A5 was introduced in May 1942 all air cooled
Caliber .30 Browning
machine guns were still required to be equipped with a bolt latch who's
primary purpose was to prevent
The A5 was no exception to the rule.
When the handle is pulled to the rear the front
rectangular cut on the bottom of the retracting bar will engage the bottom of
the rear guide and the spring loaded plunger in the rear guide that normally keeps the
retracting bar when fully forward from flopping around during firing exerts
enough downward pressure on the bar to hold the bolt to the rear.
When the retracting bar is fully forward against the stop
pin the plunger
engages the half round cut on the top rear of the retracting bar preventing
the bar from sliding to the rear from vibration and being jerked forward as
the cocking stud reciprocates with the bolt during the firing cycle.
This retracting bar or "Handle Assembly" does not
reciprocate like the A4 bolt handle when firing, rather, the cocking stud
installed in the bolt in lieu the bolt handle moves back and forth.
The handle assembly is only used to retract the bolt to
start the loading cycle or to clear a stoppage like the charging handle of the M16
rifle or the
To load the weapon the handle is pulled to the rear
and released for the "half load" and pulled and released a second time for
the "full load" just like the other M1919's being loaded with
the top cover closed.
This cut, also from the April 1947 SNL shows the
individual parts that make up the cover detent group. Like most
"exploded" drawings it is difficult to see exactly how the parts interact.
This drawing gives two views of the cover detent group
parts and their relationship with the casing and top cover. The bolt
head doesn't stick out much farther then the mount adaptor on the bottom of
The note at the bottom indicates that this drawing
superseded C74974 which is one of the drawings mentioned in the OCM Item
This is the original assembly drawing prepared by by RIA
showing the details of the retracting handle and the stop pin which allowed
the retracting bar to be properly positioned for the spring/plunger to hold
the handle and prevent the assembly from being pulled too far forward by the bolt returning to battery.
Note the date, May 14, 1941, a year before the M1919A5
became a Standard Item and the information in the "Drg. Pertains To" block
indicating that this part was originally intended for modifying M1919A4
Fixed weapons as mentioned in the OCM Item # 17705.
There are no authorizing signatures, and the assembly was
supposed to be piece marked B170985.
The vertical note on the right margin is interpreted to
mean that this assembly was intended to be used on Light Tank M2A4 & M3.
Revision 3 to drawing B170985 (2-25-43) changed the style
of the "knob" to the rod style note that imprinting the piece mark on the
retracting bar is no longer required.
The rod style "knob" and the bell style are nearly
identical to the standard A4 bolt handles except for the length of the
Drawing C90722 Revision 2 (1-27-43) is the M1919A5 right
side plate assembly drawing showing guides and spacers, note that there is
no provision for the rivet used to mount a bolt latch like the M1919A4 fixed model as the
retracting handle serves the same function.
The guides and spacers are riveted to the side plate,
later most M37's used bolts and safety wires to
attach the guides to the side plate.
This assembly drawing does not show the spring loaded
plunger that holds the slide in position.
This Draftsman's Work Order is what changed the design of
the knob from bell shaped to rod style. Note that there is no
reference to "O.O." letters of authorization for the change, just a
telephone conversion between two rather junior Ordnance officers, one in the
Chief of Ordnance's office and one at RIA.
This change in design was to be implemented at the
discretion of the manufacturer (along with the Ordnance District supervising
the contract) in a way that was to avoid increased cost to the government.
This wording or similar notations appear on many design
changes, which may explain why some changes were slow to be
The bolt handle of the M1919A4 was replaced by what was
originally called "Stud, bolt" and was used on the M1918M1 and M1919 Browning Aircraft
Machine Guns which had a similar bolt retracting design.
The original drawing, A20545, for the stud dates from
April 4, 1927 when the Class and Division drawing was converted to the new
letter prefix system.
This rather grainy reproduction of A20545 Revision 5 shows
the take down pin being added by revision 4 (2-19-43).
This Draftsman's Work Order gives some insight to how the
Ordnance Department operated.
There are two changes in play here directed by two
different "O.O." letters of authorization all rolled up into one revision.
The earliest change is dated 1-13-43 and it is merely an administrative
issue, removing two weapons, both obsolete aircraft machine guns, from the
list of weapons that the part depicted in this particular drawing pertains
The second, dated 2-8-43 authorized a design change to the
part to provide "a lock frame dissembling tool", the take down pin.
This change, Revision 4, resulted in a suffix change to the piece
mark, adding -4 to the original A20545 piece mark even though the part was
never actually imprinted with the piece mark at all.
Revision dates were specified by the authorizing letter
and usually differed from the actual dates when the drawings were revised.
Ordnance must have thought the take down pin was an
important improvement as they indicate that this change was mandatory and
was to be implemented ASAP without interfering with production schedules.
This would be another case where the Ordnance District
supervising the contract would negotiate with the manufacturer for the
timing of the change in part design.
Here's an actual picture of the A20545-4 Stud courtesy of
Goldsmith in Volume 1 of the The Browning Machine Gun,
which is a must have for the serious student of this weapon, indicates that
about 40,000 M1919A5's were produced.
According to Goldsmith's figures in Volume 1 RIA
manufactured about 14,300 A5's and likely converted the 3,000 A4's mentioned
in OCM Item 17705 the balance of the 40,000 could have been produced
by Saginaw Steering Gear or Buffalo Arms.
Production of the A5 at RIA ended in April of 1943 and the M3 light tanks were declared obsolete
in the fall of 1943.
By the end of the M3 light tank production in October 1943
about 13,900 had been produced not all of which required the A5 for coaxial
If the 40,000 figure is accurate, and there is no reason
to believe its not, the army ended up with quite a few A5's and A4 Fixed
models and nothing to use them on.
That's when the fun started.
The demand for A4 Flexible and the new M1919A6 provided the impetus for the
conversion of many A4 Fixed and A5 models to be converted into something
Since the basic mechanisms for the weapons were all the same, it
was a simple matter to convert weapons into a more desirable form.
Converting A4 Fixed to A4 Flexible was as simple as
changing out the back plate assembly, you didn't even have to remark the
side plates as the markings were the same.
M1919A5 to A4 or A6 only required removing the retracting
handle, guides, adding sights, switching out the back plate and providing a
bolt handle in lieu of the bolt stud and adding any model specific parts
required and remarking the side plate.
This picture is of a M1919A4/A5/A6 taken by the author at
through the courtesy of the RIA Museum.
The bolt handle is missing and the stock clamp is
positioned incorrectly but this picture shows the 4 holes formerly used to
rivet on the retracting bar guides, the EB inspectors mark, RIA rebuild
stamp which was not really required because the weapon was modified at the
same facility that originally built it, indicate a rebuild
that took place after Elmer Bjerke assumed his duties as Inspector of Small
Arms in January of 1947.
One interesting thing is that this particular serial
number 302743 should have been produced in 1941, however if it began life as
an A4 as the side plate markings suggest, there should be a rivet hole in
the right side plate for attachment of a bolt latch.
There are a couple of scenarios to explain the lack of the
One would be that the plates were not serialized or used
in numerical order and this plate did not get to the top of the pile until
after May 1943 when the bolt latch was eliminated.
Another would be this plate was an A4 converted into
an A5 before assembly to the casing being an A5 it would not need the rivet
hole because A5's were not equipped with bolt latches.
It is possible that this particular weapon never left RIA
and its entire service life was as a test bed for various designs.
The RIA Museum's collection contains many "one-of-a-kind"
odd ball weapons including a M1919 having bolt handle slots in both
side plates, an early attempt at dual feed capability.
The idea of utilizing whatever was at hand to produce the
weapons needed extended all the way to the April 1970 Depot Maintenance Work
Requirements document pictured below.
Paragraph 9 f contains the directive to use
various "assets" to produce needed weapons.
The M1919A5 story is, in my opinion, an interesting view
of how the Ordnance Department grappled with the need to produce weapons
under wartime conditions.
I hope you found reading this article as interesting as I
have had researching and writing it.
Its time to close this chapter in the history of the M1919
and thank all those who made this possible.
The Rock Island Arsenal Museum Staff
and in particular Jodie Creen Wesemann Museum Specialist-Registrar for
Without these dedicated people much of the history
of the M1919's would have disappeared into the mists of time. All of
the documents reproduced in this article not otherwise credited were
provided through the courtesy of the Rock Island Arsenal Museum.
Rollin Lofdahl who provided photos and real world
knowledge of M1919A5 parts.
Tom Chial who provided cuts from TM's and FM's that help
to give perspective to the subject.