Is anyone building an FCU from parts? I would love to hear about your experiences. Which parts are available and which ones are hard to get?

quote:

Originally posted by fbmg:
Is anyone building an FCU from parts? I would love to hear about your experiences. Which parts are available and which ones are hard to get?

I've done 3 so far.
Not for the ham-handed folk, but not very difficult.

The parts stream is sketchy...the "hard-to-find" part varies from one time frame to another.
Right now it is the Takedown Safety Lever.
This is an internal part, not the external Takedown Lever.

The SIG Guy has by far, the best How-To SIG videos on the Web.
Many have tried, but SIG Guy has crushed them.
He is crystal-clear, patient and concise.
https://www.youtube.com/c/SigGuy/videos

Experiences ?

Trigger bar spring
Many get baffled by this and end up bending the spring.
If you find yourself wanting to reach for the pliers, STOP !
You're doing it wrong.
Watch the SIG Guy video for the Easy Way.

Pins
All P320 pins push in easily except for the Spirol (roll) pin that must be driven through the Sear Housing.
If you find yourself wanting to hammer on a pin other than the Sear Housing Pin STOP, something is misaligned.
Well, full disclosure, you can lightly tap on a stubborn pin....I sometimes use a rawhide craft hammer to "nudge" a pin.
The taps are extremely light.

The hardest thing I've done is to change out the Sear Springs with trigger, trigger bar and takedown safety lever still in place.
That's more difficult than assembly from a bare FCU chassis.

I have an Armory Craft fully adjustable trigger and didn't want to break the Loctite and remove the trigger.

There are two armorer's blocks available that are specific to P320.
The Sig Armorer's and Gray Guns.
The GG is superior for supporting the FCU to drive the Sear Housing Pin.
The SA is handy for all the things that it does.
I have both.

3mm and 4mm alignment tools.
SG has them as well as Squirrel Daddy.

A 90° pick is handy for manipulating the Takedown Safety Lever spring.
I use a re-purposed dental pick.

This message has been edited. Last edited by: DirectDrive,

DD hit the nail on the head... with everything. Takedown Lever was the hardest to find.
Luckily, I purchased 2 takedown safety levers (waited 3 weeks for delivery) when people were buying everything.


Also, SIG guy is my ideal go to video watch. Very detailed and easy to follow.

Thanks for all the feedback. Very helpful. I just found fully assembled complete P320 FCU's at I-5 Guns in Lacey WA.