AR Workbench...
..

..
Mil Spec Carry Handle  
Sight Tower Guide Pin... 
..
The above tower guide pin  
is made from a suitable size 
machine screw or a partially
threaded machine screw. Guide 
pin requires a new access for 
the elevation wheel spring and
bearing. How to pictured below.
..
Wearing eye protection remove 
the screw head. Use a drill, file
etc. to remove threads until pin 
fits the sight tower bore. The 
guide pin should have a squared
shoulder between the ground
portion and threaded portion.
..
Note: Tap should be metric if 
a screw with SAE threads is
used and vise versa. An 
interference fit is needed 
to stabilize the pin.
..
To thread the handle bore use 
a drill press, manually turn the 
chuck while feeding the tap.
 ..
Pin threads must not protrude
above or below the threaded 
bore. Pin length should not
interfere with the flip sights.
Use a suitable size tap to 
achieve a snug thread fit i.e.
metric tap, US pin threads.
..

..
Check elevation operation for 
pin interference. Next apply 
Red Loctite to pin threads. 
Check elevation operation
again before the Loctite sets,
elevation wheel should click 
and park on the 3/6 notch.
 ..
Guide pin above, elevation 
wheel spring/bearing mod 
below takes time and involves 
small parts and springs. Best 
to have some experience  
working on carry handles.
....

.
 More Carry Handle Help...
..

..
To install the spring and bearing 
easily in a Mil Spec Carry Handle 
drill the spring bore to a set-depth 
leaving ample material for the
bearing. Thread the bore to fit a 
M4mm x 3mm set screw with a 
2mm hex drive. Spring length 
may need to be shortened,
adjust tension with set screw.
.

.
Removing Side Play...
..
To remedy receiver side play
spot flare the inside edges of 
both lugs as shown. Example:
Measure upper takedown pin 
lug width at point to be flared. 
Next measure opening between
 lower receiver at the takedown 
pin. Subtracting measurements 
determines play. Divide play in 
half and add to upper lug width.
..
Next spot flare one side of the 
lug. File flare until close to lug 
width plus the half play measure.
Flare the opposite side and file
until the measurement between 
flares is close to lug width plus
 the total play measurement.
Touchup with Aluminum Black. 
..

.

.
Easy Does It...
..
To avoid breaking a receiver 
ear when installing the roll pin 
first measure pin diameter and 
pin bores, a .005" interference 
fit between the two is plenty. 
Size pin by file, squeezing, etc.
..
Next install the trigger guard, 
insert a snug fitting automotive 
feeler gauge between the guard 
and receiver ear as shown. Lube 
bores, position on wood block, 
align bores and tap the pin short 
of gauge contact. Move gauge 
enough to expose bore and 
complete the installation.


.

.....
Bending legs on a stiff hammer 
spring using a punch or other 
tool that fits coils as shown.
..

.

.

....
Below: A slightly loose fitting barrel 
can fit snug using high heat spray
paint applied sparingly to the 
barrel extension. Mask 
 shoulder/pin area, let dry,
lube barrel/receiver.
...

...
Thanks for visiting 
www.wheeldiamond.com
www.AR15AccuShim.com
   www.NationalMatchShim.com  
.
18" Budget Build
.
Budget Builds
.
Installation Basics
 .
National Match Shim
.
AR15AccuShim.
.
Feedback
.
Questions
..
U-Tube Customer Video
.
 WD Home

...