SIG Talk banner
Cancel
  • Notice image

    SigTalk is a forum community dedicated to SIG Sauer enthusiasts. Come join the discussion about Sig Sauer pistols and rifles, optics, hunting, gunsmithing, styles, reviews, accessories, classifieds, and more!

P320 FCU vs. Custom FCU

6220 Views 31 Replies 11 Participants Last post by  Gun1, 
Dholiday666
Sorry if this is covered somewhere else, but what's the difference between the standard M18/M17 P320 FCU (silver parts chasis) vs. the gold TIN Custom works FCU ? I know the trigger is "custom"...what else?
Reply
Save
Like
  • Like
Reactions: 2
1 - 20 of 32 Posts
M
Obviously no manual safety with the Custom Works FCU. Otherwise the only other real difference besides trigger is the TiN coating.
Reply
Save
Like
  • Like
Reactions: 4
billj47
MultiSync said:
Obviously no manual safety with the Custom Works FCU. Otherwise, the only other real difference besides trigger is the TiN coating.
Click to expand...
I agree, they are essentially the same except for paint and trigger. I have both the factory flat trigger and the Custome works and I can;t tell the difference shooting them.
Reply
Save
Like
  • Like
Reactions: 5
S
I have played with both and i can tell u that the coating on the custom fcu sucks for multiple reasons.
1. The coating comes off relatively easy in spots.
2. Makes the tolerances very tight! Even taking it in and out of the gun was a lot harder and had to put some effort into pushing it back in.
3. The coating felt rough to me so all the trigger bar surfaces were not rubbing on a smooth surface. I can polish up my regular fcu for a smoother pull but good luck on the custom.
4. The trigger that comes with the custom has what is to me a sharp edge thats not comfortable. Grayguns blows it away.
Reply
Save
Like
  • Like
Reactions: 2
Sig Bulldawg
the custom works trigger is lighter and better.
Reply
Save
Like
  • Like
Reactions: 4
Dholiday666
MultiSync said:
Obviously no manual safety with the Custom Works FCU. Otherwise the only other real difference besides trigger is the TiN coating.
Click to expand...
Thanks, I found a New take off FCU for a good price...at least to me, and I already have a Custom Works and with my new build it'll be a whole new gun no need to swap FCU's and then have my comp gun always setup.
Reply
Save
Like
  • Like
Reactions: 3
Dholiday666
I understand the coating and tolerances and agree, been there done that with triggers. On my current build I'll be using the Gray Guns Hybrid.
Reply
Save
Like
  • Like
Reactions: 2
S
Sig Bulldawg said:
the custom works trigger is lighter and better.
Click to expand...
Sorry but its not. Depends if its newer or older. I bought a brand new AXG Pro and it has as good if not better than the custom works. The takedown lever bar in fact has a better coating on it. Both my new trigger and the custom works one had reduced overtravel and better break than my old p320. I believe the rolling changes sig does has led to the current new fcus having better triggers. So its better to compare the newer fcus to the older ones. The custom works i believe is just a new fcu with a coating and different trigger shoe. If you have an old p320 you will notice the difference for sure so it seems more special.
Reply
Save
Like
  • Like
Reactions: 2
Dholiday666
Just snagged a FCU with parts for $200. I'll be selling the grip and magazines most likely
Pet supply Mesh Font Gas Parallel
See less See more
Reply
Save
Like
  • Like
Reactions: 2
T
TiN isnt an additive coating like paint, its a treatment applied to the surface molecular structure. It's measured in .0001's of an inch, parts are given a tolerance of +/- .015" normally. If the assembled clearances were tighter then that was the cause. Sounds like they took out the slop on that run of FCU's.

Firearms buyers prefer tightly fitted actions as they mistake it as a quality issue, the reality is a firearm requires clearances or it won't operate in extreme cold or dusty environments. A military gun will even rattle - yet still shoot better than most of the soldiers it's issued to.

TiN is harder to break in as the surface is hardened and will resist wear to a higher degree.That is why a lot of knives and drill bits have it. It can and still will smooth out rough edges over time and use. LIke installing a MS on the P300's, cycle it with a touch of oil 100 times while bearing down on the lever and it does slick up. Triggers, too. Cheaper than 100 rounds at the range.

For the most part the TiN on an FCU is cosmetic - there are very few actual rubbing surfaces that make contact. It just looks cool. I paid a lot of extra money one time for a high end barrel, bolt, and BCG treated that way - yet the gun sees less than 50 rounds a year. I'm not really getting my moneys worth out of it and could have saved $100's.
See less See more
Reply
Save
Like
  • Like
  • Helpful
Reactions: 4
S
Man, I don't know what to say about Sig's TiN....because other's seem to last and be great and all but sig's....seems to be garbage. Read on here about the barrels and fcus losing their coating super easy....my brother got one of their barrels and the coating wore off within 200 rds in a bunch of spots. Not what i think is supposed to happen with TiN?

I guess what I'm trying to say is I'm not impressed with sig's TiN coating and i dont feel like it adds to the fcu at all.
Reply
Save
Like
Sig Bulldawg
SpartanGoat said:
Man, I don't know what to say about Sig's TiN....because other's seem to last and be great and all but sig's....seems to be garbage. Read on here about the barrels and fcus losing their coating super easy....my brother got one of their barrels and the coating wore off within 200 rds in a bunch of spots. Not what i think is supposed to happen with TiN?

I guess what I'm trying to say is I'm not impressed with sig's TiN coating and i dont feel like it adds to the fcu at all.
Click to expand...
Then don’t get it, problem solved….Use a standard FCU and buy a trigger and trigger job.
Reply
Save
Like
S
That's my recommendation. Why pay extra for a downgrade? Just make sure its a newly made fcu....at least from Aug 2021 onwards because I can confirm that mine has that build date and has the reduced overtravel, etc.
Reply
Save
Like
Sig Bulldawg
SpartanGoat said:
That's my recommendation. Why pay extra for a downgrade? Just make sure its a newly made fcu....at least from Aug 2021 onwards because I can confirm that mine has that build date and has the reduced overtravel, etc.
Click to expand...
It’s probably going to be about the same price to make a standard FCU trigger as good as a Custom Works trigger. It’s not as simple as swapping the trigger itself, the custom triggers are quite a bit lighter. I do agree about the coating though!
Reply
Save
Like
S
Weird i havent heard they are any lighter and my two examples were the same weight.

Do you know what springs they are supposedly lightening? Haven't heard of different fcu springs.
Reply
Save
Like
Sig Bulldawg
SpartanGoat said:
Weird i havent heard they are any lighter and my two examples were the same weight.

Do you know what springs they are supposedly lightening? Haven't heard of different fcu springs.
Click to expand...
Hi mine is a good pound or so lighter, I will get out my trigger scale tomorrow and verify and take some readings and post them. That was with the stock FCU and the standard trigger. I just installed an Apex flat trigger though and it’s still feels noticeably heavier. I will post pics tomorrow. What’s also crazy is the new Custom Works FCU only had maybe 50 rounds through it compared to my standard that probably has 500 or so. I am thinking it may even lighten up a little after she smooths out…

Proof will be in the pudding once I put the scale on it tomorrow, it might be closer than I think..
Reply
Save
Like
S
Sig Bulldawg said:
Hi mine is a good pound or so lighter, I will get out my trigger scale tomorrow and verify and take some readings and post them. That was with the stock FCU and the standard trigger. I just installed an Apex flat trigger though and it’s still feels noticeably heavier. I will post pics tomorrow. What’s also crazy is the new Custom Works FCU only had maybe 50 rounds through it compared to my standard that probably has 500 or so. I am thinking it may even lighten up a little after she smooths out…

Proof will be in the pudding once I put the scale on it tomorrow, it might be closer than I think..
Click to expand...
Abd this is a new fcu right? Not an older one correct?
Reply
Save
Like
Sig Bulldawg
SpartanGoat said:
Abd this is a new fcu right? Not an older one correct?
Click to expand...
yes this is after the recall.
Reply
Save
Like
Sig Bulldawg
Here we go fresh on fresh off the trigger scale. The first picture is the standard FCU with Apex flat trigger. There are no changes to springs or anything on the FCU other than the APEX flat trigger. Note that I did my best to make sure I was as accurate as I could be on the scale placement of each trigger as well. These pictures are five pull averages. I will also say the standard FCU has about 500 rounds through it.

The second picture is from a new custom works trigger that has zero modifications and about 50 rounds through it. Am I saying this is conclusive evidence with every other FCU out there in the world? No, but it’s what I am seeing out of the several FCU’s I own. I only wanted to post this because I think some people are under the impression that there is no difference in FCU’s except the coating and flat trigger.

Sleeve Yellow Font Gadget Audio equipment

Gadget Font Audio equipment Personal protective equipment Measuring instrument
See less See more
2
Reply
Save
Like
Blazer
This in an email reply just yesterday from a Sig Custom Works Tech:

"Contrary to a lot of info that is out there, the FCU’s do not differ in function from model to model. It is the same operation in every 320 FCU out there. The only differences are in the trigger (standard curved, solid flat, or skeletonized flat), and color of the FCU. We use the Titanium Nitride gold finish for our FCU’s which makes it stand out more, is better for holding up to wear, and has better lubricity than our normal FCU’s which are bead blasted stainless steel."
Reply
Save
Like
  • Like
Reactions: 3
1 - 20 of 32 Posts
SIG Talk
A forum community dedicated to SIG Sauer Pistols and SIG Sauer Rifles owners and enthusiasts. Come join the discussion about optics, hunting, gunsmithing, styles, reviews, accessories, classifieds, and more!
Full Forum Listing
Explore Our Forums
SIG Sauer Pistols 🙋‍♂️ Member Introductions Guns P250, P320, P320 X-5, M17, & M18 Pistols P365
Top