Captain Monty Mendenhall
Tim Bixler is probably best known as the co-developer of the Boatman M21 ‘radio submachine gun. Only his closest friends are aware though, that ‘Bix’ also includes being a Chicago police officer and commercial diver in his resume. Moreover, he was one of the first people, perhaps the first person to buy a Gyrojet rocket launching pistol. It is probably a safe bet too that Bix is the only cop to have carried a Gyrojet.
often has a table at the Knob Creek Gun Show. In spite of being busy, he is very approachable and willing to share
his wealth of knowledge. ‘Bix’
gave the following interview and has kindly granted permission to publish it.
When did you first learn about the Gyrojet pistols?
In 1965. SHOTGUN NEWS was a monthly publication then. There was an ad
in it for Gyrojets, so I went down to the bank and cashed in my Christmas
Club. I ordered one and some
ammo. It came on September 9.
Packed with the Gyrojet pistol was a letter saying that they were
holding a Gyrojet carbine with a matching serial number, 67, for me if I
wanted the set. As I recall the
price was about $300 or $350. Anyway,
I went down to the bank and cashed in my other Christmas Club.
Everything considered, that was a smart investment.
Well nobody could have
guessed then. At that time I was
a city cop in Chicago and money was a little tight.
Bix, you said that you once met MBA’s President, Bob
Mainhardt, face to face.
That’s right Monty. Along
comes the SHOT Show. It was held
at McCormick place in Chicago then. I
bummed an entry badge from a friend of mine who ran the Chicago Ridge Gun
Chicago, if you are a police officer you are required to carry a firearm
twenty-four hours a day. On duty,
you were required to carry a blue S&W or Colt four inch revolver that was
capable of firing .38 Special ammo. I
carried a Colt Python but it was loaded with 200 grain 38 Special.
We didn’t have frangible ammo back then. If your supervisor caught you carrying it loaded with .357
Magnum ammo, you got three days off and that was a lot more serious than the
average civilian realizes.
city didn’t really care what you carried though when you were off duty, a
.22 derringer or a .44 magnum. In
that time frame there were no .50 caliber pistols.
I remember that one kid, back in The Chicago Police Academy, asked,
“What do you do if you go swimming”’
“The instructor replied put it in a plastic bag and stuff it up your
off I went to the SHOT Show with my Gyrojet tucked into a holster under my
sport coat. At the show, there
was a booth, in fact there was a room there, for MBA.
Bob Mainhardt, the president of MBA, was there and he was telling me
about the Gyrojet. I said,
“Yeah, I have a couple.” He
looked at my tag kind of quizzically and I said, “I’m Bix. Then he said “Oh, I didn’t recognize the name on the badge.”
said, “I just borrowed it from a friend ‘cause I’m really not supposed
to be here” and we talked Gyrojets for a while. I must have mentioned that I was a cop because Bob asked, “What do
Chicago cops carry?”
just opened my sport coat and the Gyrojet was there.
He about s***.
really blew his mind.
after that, we got to talking much more personally. He really thought it was
kick that a Chicago cop would carry one of his guns so early in the maturation
of his company.
asked Bob about other guns and he said “I’ve got a couple of the experimental,
but in reality, my number 67 gun was experimental. They just weren’t calling them that.
Anyway, all of the early Gyrojets were made from the experimental
castings. These castings were
inletted, ah well not inletted, but they had the provisions for the full auto
parts. I don’t know if they had
ever had the full auto parts in them or not though.
Bob said, “We’ve got two of the experimentals that are gold in color.
We have number seven and number 13.”
said, “I’d really like to have number seven,” and he said, “Well,
we’re holding number seven for the Hollywood people that are making THE MAN
WITH THE GOLDEN GUN. That’s why we anodized them gold, but you can have number
thirteen,” and so I said, “Ok.”
either gave him some more money or we made the deal and I sent him a check
later. I don’t remember. So
that’s how I got number 13. Later
I got number 5088, which was the snub nosed Gyrojet.
also had a survival gun there that shot a round that was probably twice as
long as a standard Gyrojet round. The
way it worked was that the firing pin was a screw.
You could fire regular Gyrojet ammo in semi auto and then unscrew the
firing pin about an inch, or an inch and a quarter. Then you could load a single round of the longer specialty ammo.
There were some flares and ‘sneaky Pete’ CIA stuff there for this
tried to buy one of those, but Bob said that they only had the one.
It would have been a neat gun to have had.
I got the number 13 and the snubby because of my talk with Mainhardt.
These were all 13mm guns (.51 caliber).
Did you find out anything else about Bob Mainhardt or MBA?
Bix After Bob
left, I talked with another MBA salesman and he said that Bob Mainhardt had
gotten the money to start MBA by winning a contest to build nuclear reactor
that could fit into an eighteen wheeler trailer. That was a pretty small reactor, especially for its day.
It was a $100,000 prize, which as you know was a lot more money then
than it is today. That was the
‘seed’ money for MBA.
also said that at one time Mainhardt had been the chief assistant to Werner
von Braun. I forgot to ask
though if that was in Germany or after von Braun came to America.
were also some deep scars on the back of Mainhardt’s neck. They disappeared
down below his collar. This would
lead you to believe that he was involved in some kind of a rocket accident. I never asked him about it. Its something I’ve never forgotten. It was bad.
You must have had some of the first Gyrojet ammo that was ever
All these rounds that I had, about a hundred, were handmade. They were
made of copper and you could see how they were spun in a lathe. There was a
silver tip in front that was made of a heavier metal. It might have been
stainless steel but I doubt it. It’s been a long time.
Tell me a little about your experiences while shooting
A friend and I went to El
Paso, Texas, and I took my Gyrojets along. We went out into the desert with the guy that I went there to visit. There was an old car out there and we shot it.
We were pretty impressed with the gun. It made big holes in the sheet metal, and as you know, cars were built
better back then.
a year or so later, I got on the Chicago Police Marine Unit that they had at
the time. They had six boats that
patrolled Lake Michigan and assisted the Coast Guard.
We did rescue stuff and sometimes recovered bodies and what-have-you in
the lake. It was kind of like a
summer vacation for a cop on the payroll.
I had a city credit card to buy gas for the boat. We’d just go out there and play. It was the neatest thing that I have ever done as far as working goes.
did do a lot of police work too, but there was a lot of leisure time in the
Marine Unit. When there was nothing going on, we’d take the boat out a
couple of miles and swim.
we’d take some machineguns out there that we weren’t supposed to have and
shot them out on the lake. Cops
have always kind of felt that they were immune to whatever laws they had to
enforce and that’s no major secret.
once took my Gyrojet out there, number 67, and the scuba gear. I jumped off of the police boat and went down about, I don’t know,
five or ten feet, and I shot the Gyrojet underwater.
It was really, really neat. The
bullet went out but it left a spiral trace of bubbles from the four rocket
nozzles. As the rounds got farther out, I imagine about five or ten feet, but
this has been a long time, the bubbles expanded.
When I looked where the round had been, and I have no idea how far it
went but probably not too far after the burn out, the bubbles kind of
expanded. It was kind of like
looking down the big end of a megaphone. That’s the best way I can describe it.
As they were expanding, they were also deforming. The bubbles were trying to float up.
I can’t describe it better than that, but boy was it neat.
shooting a few rounds like that, then, from about five feet under water, I
shot a couple up into the air. They
went to the surface but the bubbles didn’t deform the same way.
Since they were going up, the spirals stayed round.
You probably don’t care about all this but it was neat and I am
reliving all this in my mind as I tell it.
after I shot five or ten more rounds, I came up and my partner on the boat
said, “Man! What were you doing?” I
said I was just playing with this gun I got. He said, “Things were coming out of the water going ‘ phew’ up in
put me in mind of the atomic submarines launching missiles.
I know that’s an exaggeration but it was neat.
When I did my recent Gyrojet tests, I had a few failures to
ignite. Did you have any
problems? You were shooting
rockets that were almost new.
I shot a few rounds that
sizzled, not many though, two or three out of a hundred.
When the round went off, it didn’t go anywhere. It just sat there and
went ‘whoosh.’ After that you
had to dump it out of the gun and there was a lot of carbon residue that wiped
off rather easily.
Uh Monty, I had another interesting experience because of the Gyrojets. The ATU once came to my house when I was a cop. I had a Federal Firearms license then too. My mother came to the door and the agent said that he wanted to talk to Bix. She said, “He’s at work. You know he’s a city policeman.” The agent said, “No I didn’t. I’ll be back”
evening two agents showed up. They
said we are offering (and this was all b******** too) all policemen who have
FFLs an opportunity to surrender them before they cracked down on people who
have FFL’s but who are not truly in the firearms business.
We got to talking and they looked my record book and at the Gyrojets too and they said, “We don’t think that these are guns.” I said, “What are they?” He replied, “Well they are rocket launchers. It’s just like you had an Atlas rocket and a launching pad in your backyard. It wouldn’t be any of our business because it’s not a gun”
was before 1968 and the new Destructive Device rule. I also had two cannons out in my garage that were listed in my book, a
37mm and a 25mm. When they saw the cannons, the whole tone of the conversation
changed. It was like, “Ok,
we’re dealing with a kook.”
You haven’t been a Chicago Policeman for a long time. Is this why you quit?
No. Not long after getting
on the Marine Unit, I went to Florida to a diving school to learn to be a
diver for the Chicago Police Department. While I was in diving school, I decided to quit the force.
I never really liked being a cop. I was brought up in one of those neighborhoods where everybody was
either a cop or a crook or a priest. I
joined the police department on a lark just to see if I could. You see Monty, there was a rumor that unless you gave a certain person
$1500 you could not be hired. Well
I took the entrance exam just to see and I got on the force. I never gave
anybody a penny either, except for the registration fee, which was $3 or
something. I remember that 2500
people took the test for the job and I came out number 42 from the top. I’ve always been a little bit proud of that. I was tired of working in a machine shop so I went on and took the job
on the Police force but I never really felt comfortable being a cop so I quit.
diving school, I moved to Morgan City, Louisiana, which was the hub of
commercial diving in the US. That’s
where most of the diving jobs were then.
Bix, I know that you a few years ago helped the NRA’s Museum to
recover some Gyrojets that the BATF had confiscated from them. How about telling the readers about that?
It’s a long story, but I don’t mind telling.
I was in Morgan City in 1968 when the amnesty happened.
In fact a friend of mine told me about the amnesty and I said, “Aw
b******,” I didn’t believe him. When
I went to the Post Office though, I saw the poster and registered the
Your Gyrojets weren’t machine guns. I know why you had to register
your Gyrojets, but many of our readers may not.
Well, I had to register my Gyrojets, not because they were machine guns
but because the ATF had ruled that anything above fifty caliber was a
Destructive Device. The 13mm
Gyrojets were .51 caliber so I had to register them.
number 67 gun had been made so that a select fire mechanism could be
installed. On a lark, I decided to register it as a machine gun.
me make a little aside here about the installation and removal of full auto
parts. Before 1968 a Class Five
did what a Class Two does now. He
could remove the full auto parts from a machine gun, like an M2 Carbine and
tell the ATU (they were called the ATU then for Alcohol, Tobacco Unit), and
they would remove the M2 from the Federal registry and it could be sold like
any other semi auto gun. After
1968, the one way conversion ruling was adopted. This may be interesting to
you because you write about other stuff than Gyrojets. This ruling is why a
1927 Thompson can still be carried as a semi auto if it has not had any full
auto parts in it since 1968.
Thompson's were once full auto 1921s. John
Thompson didn’t design the Thompson submachine gun you know.
He was just the guy who had the foresight to see the need for a weapon
of this type. Well, he got some
investors and hired Oscar Payne and Theodore Eickoff.
These two are the real designers and
Warner-Swasey actually manufactured all of the prototype Thompson's.
after they got the prototype Thompson perfected, John Thompson paid Colt
Firearms to manufacture 15,000 Thompson Submachine Guns. By the time they were ready though, nobody really wanted them. The war
had been over for three years. Sales
were really slow. To try to get a
little more cash flow, they just converted some full auto 1921s to semi auto
and called them 1927 models. The
semi autos didn’t sell very well either.
any rate if you ever try to transfer a semi auto ’27, the ATF may try to
change the classification from a semi auto to a machine gun.
If you argue with them though, and especially if you talk to one of the
guys who have been there a while ‘cause they are very knowledgeable, you can
explain that this is a semi auto ’27 and that registering it as a full auto
lowers its value a lot. Somebody
who knows will listen and leave the registration as a short barreled rifle. That still has the same $200 tax as a machine gun though.
never were a lot of 1927 Thompson's anyway. Of those few, there aren’t many left that haven’t been reconverted
back to full auto or if they haven’t been, they are now registered as a full
have a ‘27A and when it came to me the ATF tried to change the paperwork and
I said, “I don’t want it changed.” So we went through this and we used the M2 Carbine story as the basis
for keeping it as a ‘short barreled carbine.’ And in truth it probably should be a $5 transfer tax item but I’m not
going to fight that. It’s my
prize possession, my 1927 Thompson.
back on the Gyrojet story. Where was I? The amnesty came along and I said well, “if I’m going to register
these things as DD’s, why not put the full auto parts into them and register
them as DD machine guns?”
What was involved in the full auto conversion Bix?
To answer your question, I don’t remember exactly what was required
to do that. I know that when I
looked at the receiver I could figure it out back then so I could figure it
out again today. I have no reason
to do that, but it could be done. So I registered all four of my Gyrojets and
the registrations came back on the three that I registered as full auto but
not on the snubby (s.n. B5088S). That
one came back stamped “REGISTRATION NOT REQUIRED.”
Here is a color copy of both sides of the form for you to keep.
This is the famous form from the NRA confiscation case.
Monty This is a good place to get back to the BATF and NRA Museum incident, as I recall, the BATF confiscated the museums 13mm Gyrojets because they were not registered as Destructive Devices. How did you get involved in helping the museum to get its Gyrojets back?
Bix You see Monty, the Mark I Gyrojet “A” frame series
guns had their castings inletted for the full auto parts. I registered all of my Mark I, “A” frame Gyrojets as
machine guns. There was my first pistol, a Mark I, serial number A067, the
carbine, serial number A0067 (MBA just added a ‘0’ to the serial number
for some reason) and the gold plated pistol, A013.
I tried to register my snubby Gyrojet (B5088S) as a destructive device,
but the ATU wouldn’t let me. That’s
the one that came back with the for stamp, REGISTRATION NOT REQUIRED, the one
that helped to recover the NRA’s 13mm Gyrojets
After the BATF confiscated the NRA Museum’s unregistered 13mm Gyrojets, somebody at the NRA learned about this 13mm Gyrojet registration form that I had that had came back stamped “REGISTRATION NOT REQUIRED.” The NRA wanted to see a copy of it, so I sent them copies of the BATF’s paperwork. The NRA got their Gyrojets back pretty soon after that.
You don’t still have these Gyrojets do you?
No. There came a time when I couldn’t get ammo anymore. The Gyrojet thing sort of petered out like the Dardick thing
did. I had one of those too.
I ran an ad in Shotgun News and nobody responded for a while but then I
got a telegram from Canada from Eric Davidson.
called him up and he wanted to buy my Gyrojets.
He flew down from Canada and bought the guns.
He had a permit to own pistols in Canada and so we did a test on the
paperwork. I did the
exportation paperwork as machine guns. I
did take the full auto parts out first though. I also wrote a letter to go along with the guns to the Canadian import
officials saying that these Gyrojets were registered as machine guns in the
US, but they aren’t really machine guns anymore because the full auto parts
have been removed. I exported
them through a freight forwarder after ATF approved the export paperwork.
They went through fine.
about all that there is to it except that I also sent Eric Davidson a book
that I had. It was called
“Gyrojet Rocket Technology.” Somebody
at MBA offered that to me at the same time that they sold the Gyrojets to me.
I thought, “What the heck, I might as well buy a book.”
It had a lot of Gyrojet theory in it.
I found out later that this book was not supposed to be released from
MBA. It was sold by the sales force to make an extra ten bucks,
but when the technical people found out, they had fit because it told all of
Thanks for your sharing your recollections Bix. They were very interesting.
I was not surprised to learn that you had ‘fizzles’ with new ammo. In the data that came from MBA, the book that was not supposed to be
released, they reported a success rate of 99% at best. In some places, the stated rate of failure was much worse.
|Gyrojet Reviews||Gyrojet Inaccuracy|