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Technical Information


The following topics will be covered in this page:

1. Blade Steel

2. The Hammerhead Lock (patent pending)

3. Removing and Installing the 1911 Grips

4. Installing the Pocket Clip (new & old)

5. Trouble Shooting




Ultimate Equipment has selected 2 types of premium stainless blade steel to make the M1911 Knives.  Here is a detailed comparison between the two steels:


CPM S35VN is a martensitic stainless steel designed to offer
improved toughness over CPM S30V. It is also easier to machine
and polish than CPM S30V. Its chemistry has been rebalanced
so that it forms some niobium carbides along with vanadium and
chromium carbides. Substituting niobium carbides for some of the
vanadium carbides makes CPM S35VN about 15-20% tougher
than CPM S30V without any loss of wear resistance. CPM S35VN’s
improved toughness gives it better resistance to edge chipping.
Because both vanadium and niobium carbides are harder and more
effective than chromium carbides in providing wear resistance,
the CPM stainless blade steels offer improved edge retention
over conventional high chromium steels such as 440C and D2.
The CPM process produces very homogeneous, high quality
steel characterized by superior dimensional stability, grindability,
and toughness compared to steels produced by conventional
melting practices.
Retention (CATRA Testing Relative to 440C)
Grade %
CPM S35VN 145*
CPM S30V 145
154CM 120
440C 100
The CATRA (Cutlery & Allied Trades Research Association) test
machine performs a standard cutting operation and measures the
number of silica impregnated cards which are cut. It is considered
a measure of relative wear resistance, reported in this table as
compared to a 440C standard.
*Estimate based upon market feedback
Long-Wearing Specialty Cutlery
Plastic Injection and Extrusion Feed Screws and Dies
Non-Return Valve Components
Pelletizing Equipment
Wear Components for Food and Chemical Processing
Note: These are some typical applications. Your specific application should
not be undertaken without independent study and evaluation for suitability.
Issue #1
Carbon 1.40%
Chromium 14.00%
Vanadium 3.00%
Molybdenum 2.00%
Niobium 0.50%
CPM Steel Conventional Steel
Elastic Modulus 32 X 106 psi (221 GPa)
Density 0.27 lbs./in3 (7.47 g/cm3)
Thermal Conductivity
BTU/hr-ft-°F W/m-°K cal/cm-s-°C
200°F 93°C 10 17.31 4.13 X 10-2
Coefficient of Thermal Expansion
°F °C in/in/°F mm/mm/°C
70 - 400 (20 - 200) 6.1 X10-6 (11.0 X10-6)
70 - 600 (20 - 315) 6.4 X10-6 (11.5 X10-6)
Tool Steel Comparagraph
Physical Properties
Mechanical Properties
Typical Applications
Carbide Type and Volume
Vanadium Niobium Chromium Total
CPM S35VN 3.0% 0.5% 10.5% 14.0%
CPM S30V 4.0% 10.5% 14.5%
440C 0% 12.0% 12.0%
154 CM 0% 17.5% 17.5%
CPM S90V 9.0% 11.0% 20.0%
Toughness (Transverse Charpy C-notch Testing)
Grade Impact Energy
CPM S35VN 12.0 ft. lbs.
CPM S30V 10.0 ft. lbs.
154CM 2.5 ft. lbs.
440C 2.5 ft. lbs.


440C 154 CM CPM S30V
*vs. Hg/HgO reference electrode


Forging: 2100°F (1150°C) Do not forge below 1750°F (950°C).
Annealing: Heat to 1650°F (900°C), hold 2 hours, slow cool no
faster than 25°F (15°C) per hour to 1100°F (595°C), then furnace
cool or cool in still air to room temperature.
Annealed Hardness: About BHN 255
Stress Relieving
Annealed Parts: Heat to 1100-1300°F (595-705°C), hold 2
hours, then furnace cool or cool in still air.
Hardened Parts: Heat to 25-50°F (15-30°C) below
original tempering temperature, hold 2 hours, then
furnace cool or cool in still air.
Straightening: Best done warm 400-800°F (200-425°C)
Preheat: Heat to 1550-1600°F (845-870°C) Equalize.
Austenitize: 1900-2000°F (1035-1095°C), hold time at temperature
15-30 minutes.
Quench: Air or positive pressure quench (2 bar minimum) to
below 125°F (50°C), or salt or interrupted oil quench to about
1000°F (540°C), then air cool to below 125°F (50°C).
Temper: Double temper at 400-750°F (200-400°C). Hold for
2 hours minimum each time. (See Table) A freezing treatment
may be used between the first and second tempers. Freezing
treatments help to attain maximum hardenability and must
always be followed by at least one temper.
NOTE: For optimum stress relieving, CPM S35VN may be tempered
at 1000-1025°F (540-550°C). Tempering in this range may
result in a slight decrease in corrosion resistance.
Size Change: +0.05 to +0.10% when fully martensitic. The
presence of retained austenite may reduce the net growth.
When tempering at 400-750°F (200-400°C), freezing treatments
may be necessary to minimize retained austenite.
Note: Properties shown throughout this data sheet are typical values.
Normal variations in chemistry, size and heat treat conditions may cause
deviations from these values.
Recommended Heat Treatment:
Austenitize 1950°F (1065°C). Quench to below 125°F (50°C).
Double temper at 600°F (315°C) 2 hrs. minimum each temper.
Cool to hand warm between tempers. A freezing treatment may
be added between tempers.
Aim hardness: 58-61 HRC.
Thermal Treatments
Tempering Temperature °F (°C)
Hardness (HRC)
Oil Quench + (200°C) (315°C) (540°C)
Freeze -112°F
Heat Treat Response - Hardness (HRC)
Austenitizing Temperature
1900°F 1950°F 2000°F
(1040°C) (1065°C) (1095°C)
Oil Oil + Oil Oil + Oil Oil +
Tempering Freeze Freeze Freeze
Temperature -112°F -112°F -112°F
As Quenched
400°F (200°C)
600°F (315°C)
1000°F (540°C)
Results may vary with hardening method and section size. Salt or oil quenching will give
maximum response. Vacuum or atmosphere cooling may result in up to 1-2 HRC points lower.
Minimum Time
at Aust. Temp. 30 min. 30 min. 15 min.
Minimum Number
of Tempers 2 2 2
Machinability and Grindability
In the annealed condition, CPM S35VN is much easier to
machine than CPM S90V and easier to machine than
CPM S30V. Similar grinding equipment and practices
used for high speed steels are recommended. “SG” type
alumina wheels or CBN wheels have generally given the
best performance with CPM steels.









* Information and comparagraph from Crucibles USA.



B. 440C Stainless Steel

440C is a tough and relatively corrosion resistant martensitic stainless steel that maintains a good edge. For many years, 440C was the benchmark cutlery steel, and even today, represents an excellent choice for knife making that would fit most people's requirements. Its characteristics in general however do make it inferior toCPM S30V in most ways including corrosion resistance, wear resistance, hardenability and edge holding.

The microstructure of 440C is not as fine and uniform as CPM S30V, which results it the steel not taking as fine an edge, and can cause some chipping as well. It is still used by many knife makers because it is easier to work with than CPM S30V or any of the other "super steels", and as some claim, can perform even better with a Cryo or Dry Ice Quench. 440C can be hardened to about HRC 60 in use.

Some makers using 440C extensively include Swiss company Klotzli and Canadian custom knife maker George Tichbourne. 440C belongs to the family of stainless steels that include 440A and 440B, the major differences being the variance in carbon content.

























Values are shown in percentages.


2. Hammerhead Lock (patent pending)

Ultimate Equipment's innovative Hammerhead Lock™ is a perfect example of the K.I.S.S. principle.

This truly ambidextrous design enables any user to open and close the knife with one hand - actually with only 2 fingers. When opening the knife, the blade snaps into locking position with authority. The fun part is when you are unlocking the knife and closing it - the only thing you need to do is to push the locking stud up with your thumb, and at the same time press the blade down with your index finger, without placing any of your fingers in the path of the closing blade.

Hammerhead 3  Hammerhead 2  Hammerhead 4  Hammerhead 1

Some other designs have to use omega springs to make this happen. Tiny springs will break sooner or later, and it is painful to replace them. Fortunately, the Hammerhead Lock does not use any tiny springs. Similar to a traditional lock-back, it gets the locking force from the heavy duty bar spring at the back, which will never break or wear out.

As a result, the Hammerhead is extremely durable, and also easy to clean due to its simplicity and fewer number of parts. When dirt and mud gets in the knife, just brush or blow them off, and keep on cutting.



Removing the grips from the knife is as simple as removing the grips from your 1911 pistol.  Use the enclosed hex key to lift the grip screws, and then the grips can be removed.

Sometimes the grips could be pretty tight on the grip bushings, due to shrinkage of wood.  Remove the one that comes off more easily first, open the blade, and knock on the back of the difficult one.  In this way you won't hurt your finger nails.

Try not to pry the grip panel off with a blade.  If both grips are tight and you have to pry to lift one of them, use a small screw driver and pry carefully from the clip slot at the butt.  Just pry a little so the grip is lifted.

And yes, all grip panels on the M1911 knives are standard sized pistol grips, and can be installed on any standard 1911 pistols.  And any standard 1911 grips can be installed on the knife, too.  This allows you to customize your knife or gun, or even making a matching gun-and-knife set!



The M1911 Folding Knife is designed to be tip-up carried. It enables a fast and natural draw and open motion.  We now have a new flat pocket clip, which is a solid improvement on the old wire pocket clips.  Here is an illustrated instruction on how to install the new flat pocket clip.

a. First, decide which side you want to have the clip installed. 

     For right-handers, it is usually on the right hand side.

b. Remove the grip on the OPPOSITE side of the handle.

     (If you want the clip on the right hand side, remove the grip on the left side.)

c. Remove the old clip screw, which is too big for the new clip.  The new clip comes with its own clip screw.

d. Take the clip screw off the new clip, and insert end into the slot between the grip and the butt of the knife. 

     This should be on the same side that you want the clip installed.

e. Put the new clip screw through the hole from the opposite side, and tighten it. 

     Make sure you align the clip correctly, and hold it firmly when you tighten.

     You may need to loosen and re-tighten it to adjust the clip's angle.

f. After this, the clip should stay firmly in place. Install the grip back onto the handle.


clip5  clip4  clip3


clip2  clip1  clip6




Here below are some possible issues some users could encounter.  Follow the tips here to try to solve the problems by yourself.  If you have other issues or something cannot be easily fixed, please contact Gunner Products by email ( 

The unlocking thumb stud seems to be stiff.  It is not easy to unlock the knife with one hand.

Locking mechanism of the knives were carefully precision cut to have a very tight fit, in order to ensure a rock-solid lock.  And I hardened the main spring for the same purpose.

Before we ship a knife out, we carefully inspect every single one, make sure the spring tension is right and one can open and close the knife easily with one hand.  So when you receive a new knife that feels stiff to you, do not throw it away.  Instead, use TWO thumbs to unlock the blade during the first 40 - 50 opening and closings.  At the same time, try placing your fingers on different spots and see which position provides the most control. 

Note: Give it some time.  Play with it.  It is a break-in process mainly for the user.  When you open and close the knife, you are learning how to place your fingers at the right place to control the blade close.  After you get used to closing the blade, the "stiff" lock will not feel stiff at all.