Sig P365 Series Flat vs Curved Trigger

[Alllen Bundy]

As you can see by the photos, the only real difference between the curved trigger and the flat trigger is the shape.





The lever arm actuating the trigger linkage bar is the same length on both triggers. Both triggers are the same length. The amount of force required to be applied to the end of the trigger to actuate the sear is the same. So one trigger is not going to be appreciably safer than the other for concealed carry.

The only real difference between the P365 FCU and the P365XL FCU is the trigger shape. There is no difference between the break of the flat trigger vs the curved trigger, as all other parts in the FCUs are the same.

MGW: Sig Flat Trigger: $47.57

MGW: Sig Curved Trigger Kit with Trigger Spring and Pivot pin: $18.48

Both triggers use about the same amount of steel and are nearly the same shape. There is no real cost difference in manufacturing either of them. It's not a low volume aftermarket trigger. It's a production trigger still in use for the P365X and P365XL. So why does the flat trigger cost $29 more? It seems like Sig is price gouging to me.

Someone with a large diameter trigger finger is going to be contacting nearly the same point on either trigger, so there isn't going to be much, if any, difference in the trigger pull force required to actuate the sear. However, the point of contact on the flat trigger is about 1/8" further forward than that on the curved trigger, so it will feel somewhat different.

Pros of the flat trigger:

Someone with a smaller diameter trigger finger will be able to contact the trigger further outward on the flat trigger, which will increase their leverage and reduce the effective trigger pull force required to actuate the sear..

Cons of the flat trigger:

There is not as much room inside of the trigger guard for a gloved finger with the flat trigger. You might start to depress the trigger as you put your gloved finger inside of the trigger guard, and the glove may also affect the trigger reset. This could be a serious issue in a cold climate.

Your finger might not contact the trigger at the same point ever time, which might reduce your accuracy and/or repeatability of your point of impact.

Pros of the curved trigger:

There is more room inside of the trigger guard for a gloved finger with the curved trigger. This is important in cold climates. With the curved trigger I can wear a pair of deerskin work gloves and still fit my trigger finger inside the trigger guard without depressing the trigger, and I have extra large hands.

Your finger will contact the trigger at the same point ever time, which might improve your accuracy and/or repeatability of your point of impact.

The curved trigger is $29 cheaper than the flat trigger.

Cons of the curved trigger:

None that I can see.

I actually prefer the feel of the curved trigger. But living here in cold MinneSnowta winters, the main selling point of the curved trigger is that it allows more room inside of the trigger guard for a gloved finger. So even if I preferred the feel of the flat trigger, I would still use the curved trigger. As such, I have replaced the flat trigger in my P365XL with a curved trigger and I will probably sell the flat trigger, or trade it for a magazine, etc.

As I see it, this is mostly a matter of personal preference between trigger shapes and which trigger feels better to you. Unless of course you live in a cold climate and you need to wear gloves outside, in which case the curved trigger would be preferable, if not mandatory, for some people.

If you have a P365 with a curved trigger I'd recommend buying more ammunition to practice with rather than buying a $47 flat trigger as a so called "upgrade".

However, if you have more than one P365 series pistol, I'd recommended deciding upon which trigger shape you prefer and then outfitting all of your P365 series pistols with the same trigger shape so you have more consistency from pistol to pistol.

If you have a P365X or P365XL and live in a cold climate, you might seriously want to consider installing the curved trigger so that your gloved trigger finger can more easily fit inside the trigger guard without depressing the trigger or affecting the trigger reset.

If trigger feel is important to you, I would be more concerned with polishing the trigger linkage contact points and sear to obtain the smoothest trigger pull possible.

To put it into perspective, my new un-broken-in P365XL with it's flat trigger felt HORRIBLE compared to my P365 with it's polished trigger linkage points and it's curved trigger with extremely smooth trigger action.

If you are going to compare the flat trigger to the curved trigger, at least do so with a very well broken-in pistol, or better yet, with a pistol that has had all of trigger linkage contact points polished. Excess friction causes more of a difference in feel than trigger shape.

For those of you with P365 series pistols, do you prefer the flat trigger or the curved trigger and why?

Are there any aftermarket triggers that you believe are superior in performance to the Sig flat or curved trigger when used in a self defense concealed carry pistol?

 

[AlexanderA]

The difference in price reflects the fact that flat triggers seem to be all the rage. Personally, I'm a traditionalist when it comes to guns. The traditional aesthetic is that triggers must be curved.

On the other hand, if you go back far enough, there are other alternatives. Here's a Near Eastern miquelet lock gun with a ball trigger, and no trigger guard.

 

[bannockburn]

Allen Bundy

Have tried both triggers and I prefer the flat one over the curved version. I believe that the flat trigger is a better fit and feels more comfortable to use for my smaller size hand.

 

[JR24]

Allen Bundy

Have tried both triggers and I prefer the flat one over the curved version. I believe that the flat trigger is a better fit and feels more comfortable to use for my smaller size hand.

Same, and I don’t have any issues getting a light glove on the trigger, either with my 365 or 226.

Flat all the way for me.

 

[Tinman357]

Bundy: Very observant. I consider my P365 to be a direct replacement for my S&W 60. But with 8 more rounds (magguts), better trigger, better sights, flatter, smaller, lighter, easier to shoot well, faster reloads.

I've followed some of your recommendations on polishing and have proved them to be a noticeable improvement and the little thing has proved to be 100% reliable.

It rides in a coat pocket or even loose fit jeans. Whats not to like?

The lube I use is my own blend that has worked very, very well. Without starting another "best lube debate" its 3oz mobile1 synthetic 30wt oil blended with 30z SuperLube synthetic grease with 1oz of synthetic ATF. Makes a thick semi liquid that stays put. I have shot it dry and it leaves a film of teflon on all the mating surfaces. Slick stuff. Fouling wipes off easy.

I have a lot of experiance and much practice with lasers and find the CT lazerguard in green to be a noteworthy addition to round out this fine little pistol.

I also have the P365XL with the short module and straight trigger. Did the same polishing mods as the other. Huge difference in it afterwards.

The XL got the CT red dot optic, something else I have a lot of time with. I got in before the mag ban in WA and have a very nice supply of 10 and 12 rd mags fitted with the 12 and 14 rd upgrades. All mags will fit either of them as I prefer the short standard grip on them.

I do prefer a longer barrel on a belt carried pistol so I went with the Tru Precision extended and threaded barrel for the XL. I even tested the Micro Comp and it does noticebly reduce recoil. Another plus in my opinion.

I've been shooting for almost 5 decades and have learned to repair and tune my own sidearms to my liking. A 1911 is still my primary carry during the 9 months that I can wear a cover garment, but the XL does summer duty. The standard p365 rides along in the cooler months as well. It's fast out of the coat pocket, crazy fast.

Now that I'm retired, I can carry what I'm most proficient/comfortable with with no worries of an accidental flash of my sidearm. The 1911 and the P365's have become my top EDC.

Thank you for your input here.

 

[TrapK80]

Currently have three Sig 365's: P365, 365X and 365XL. The X and XL have the flat trigger and the P has the curved. Of the two I prefer the flat triggers on the X and XL. At the range I can barely tell the difference. I have a flat trigger in the parts bin but really not in any hurry to change out the curved trigger. As far as the price difference of the two triggers if I were switching out a curved trigger I would take a serious look at other after market flat triggers over the factory Sig flat trigger.

 

[halfmoonclip]

Somehow, have never gone down this rabbit hole, if for no reason other than esthetics. The straight triggers just look doofy.
Perhaps need to try one.
Moon
ETA- Alexander A, love the flintlock; thanks!
M

 

[JR24]

Somehow, have never gone down this rabbit hole, if for no reason other than esthetics. The straight triggers just look doofy.
Perhaps need to try one.
Moon
ETA- Alexander A, love the flintlock; thanks!
M

Though I have stated I do prefer the flat trigger feel on the Sigs (but not my 1911s), I don’t care enough to swap out any parts.

Typically I leave a gun’s trigger alone and just learn it through dry fire and range time. Do that enough and I’ve found I can shoot any gun or trigger style well, compared to when I was a trigger snob and basically could only shoot few of my guns well.

 

[JDeere]

I like the flat trigger just fine because that's what came on my two. I will not be swapping out curved triggers on other firearms just because. It does not matter to me as I can shoot either equally well and I don't ever wear gloves so that is not even an issue.

 

[JR24]

Just for fun, since I’m in the basement doing chores. I grabbed my dry fire guns and some gloves, because this is a topic I guess.

I grabbed my “good” gloves, the ones I almost never wear unless it’s -10 or colder and I have to be outside for a long time (snowmachine, or clearing the driveway). Pretty thick gloves. I also grabbed my typical snow blowing or winter gloves, medium weight. And finally my typical gloves, which are just lightweight work gloves o bought for $5.99 at Fleet.

Thoughts:

The thick gloves didn’t fit into any trigger guards, regardless of trigger style. Glock, 1911, HK, Sig (flat or curved). But with everything but Glocks I was able to get enough trigger finger in there to pop the snap cap. Glocks I couldn’t get my gloved finger on the little dongle so firing was problematic.

Now, with these gloves I would have more trouble getting to my gun and drawing it than anything with a trigger, and shucking the glove on my main hand would be movement #1 anyway (much like was the plan hunting caribou in the tundra at -35 or worse).

Typical gloves I use for snowblowing didn’t fit into any trigger guards either, curved, flat, Sig Glock or HK, but I was able to dry fire them all on the draw just fine. No difference.

Work gloves I always wear? No change on anything, they are thin enough that it doesn’t matter.

So, my conclusion vis a vis trigger shape and gloves is what I expected, nothing different.

Also, watch out for Glock trigger dongles in real thick gloves, which with GarandThumb’s freezing test leads me to believe that single piece or hinged triggers are just better for extreme cold use.

 

[WYO]

I find it annoying that Sig put curved triggers on the standard P365 and the P365-380 but put flat triggers on the ones with the XL grip modules. This led to some adjustment issues when switching from gun to gun. Because I was used to the curved trigger when I bought my XL, and because almost all of my other guns have curved triggers. I switched my XL to a curved trigger. All is well.

 

[Ethan Verity]

I have tried flat and curved triggers in my M&P series pistols, and an AR-15, and found that I go against the grain in preferring the feel of the curved trigger over the flat... I like how the finger sinks into the exact same location of the curve, it makes for a very consistent pull each and every time no matter where your finger initially touches the trigger. If there is an imperceptibly small reduction in pull weight with the flat trigger, it's lost on me... my trigger finger isn't so weak that I worry about every fraction of a pound difference.

 

[Alllen Bundy]

I was thinking more about why people might prefer the flat trigger, and it occurred to me that with the curved trigger the contact area on your finger is larger so there will be less pressure per square inch on your finger when you squeeze the trigger. With the flat trigger with a reduced contact area on your finger, there will be a greater range of pressure as you squeeze the trigger and some people may interpret that as better control. Just a thought.

....Because I was used to the curved trigger when I bought my XL, and because almost all of my other guns have curved triggers. I switched my XL to a curved trigger.....

I like how the finger sinks into the exact same location of the curve, it makes for a very consistent pull each and every time no matter where your finger initially touches the trigger. ....... my trigger finger isn't so weak that I worry about every fraction of a pound difference.

The more consistency the better. I wouldn't have an issue with the trigger pull force being greater as long as it's smooth and not erratic.

Also, watch out for Glock trigger dongles in real thick gloves, which with GarandThumb’s freezing test leads me to believe that single piece or hinged triggers are just better for extreme cold use.

The trigger dongle always seemed problematic to me. Likewise hammers also seemed problematic in a worst case situation. A big reason that I chose the Sig P365 for my first pistol was that it was striker fired and did NOT have a trigger dongle, AND it had an optional manual trigger safety. The high magazine capacity, for the time, was just the icing on the cake. The luminous sights were the scoop of ice cream along side the cake.

Some people want to dismiss Garand Thumb's freezing test because they live in a warm area. But life is stranger than fiction and you cannot predict the most unlikely possibility that actual comes true. You could be herded into a walk-in freezer by the bad guys and you see a frozen dead guy on a meathook. But low and behold the bad guys forgot to check and you find a backup pistol strapped to the ankle of the dead guy who turned out to be an undercover cop. And it's your good fortune that the pistol is striker fired with a one piece trigger that is hinged at the top so it will likely fire even in it's frozen condition.

Even if you don't live in a cold area, Garand Thumb's freezing test proved that hammers, trigger dongles, and triggers like the 1911's are susceptible to contamination.

 

[Old Dog]

Allen Bundy

Have tried both triggers and I prefer the flat one over the curved version. I believe that the flat trigger is a better fit and feels more comfortable to use for my smaller size hand.

I also prefer the flat trigger on my XL to the curved on our 365s.

 

[Alllen Bundy]

I decided to actually measure the trigger pull force between the curved trigger and the flat trigger to see if there was any difference. The problem is trying to measure in exactly the same place on the trigger every time. One person's force measurement will vary from another person's because of how they hold the spring force gauge and exactly where on the trigger they hold it. So I decided to measure from the actual tip of the trigger. Once you know that you can calculate how much force is needed to pull the trigger at any point along the trigger.

I forged a piece of aluminum to cup it so that it could capture just the tip of the trigger. I connected a piece of steel wire to it with teflon tubing over it for minimum friction. I hooked my force gauge at the other end.



With 10 pulls of each trigger, the curved trigger released the sear with with an average of 3.78 lbs and the flat trigger released with an average of 3.77 lbs. If you pull the trigger midway between the trigger pivot and the tip of the trigger it would require about 7.5 lbs of force.

I measured the trigger pull force with 5 different sear springs and there was less than 6% difference in force between them. The two year old sear spring had the highest spring force.

I measured the trigger pull force using 6 different trigger return springs. The minimum was 3.51 lbs with a 2 year old spring and 4.09 lbs with the strongest new spring. That is about a 16.5% difference. I don't know if the two year old trigger return spring was actually losing some of it's spring force or if it was lower in spring force from the factory. The new trigger springs only had a variation in spring force of about 3.5%.

Trigger return springs are cheap. If I need to replace one every year or two to maintain the trigger pull force, and they only require a few minutes to replace, so no big deal.

The striker safety spring also adds to the trigger pull force required, but it's such a small part of it that I didn't bother to measure differences in spring force between the 3 striker safety springs that I have.

 

[doubleh]

I had a flat trigger XL. My son-in-law has the curved trigger shorter fun. I liked the flat trigger better but it was probably because it was an all over better trigger than one the curved model.

 

[Reinz]

All I care about is if the trigger functions nice; crisp, light, short reset, trigger shape is inconsequential to me.

 

[CNobbe]

Thoughts:

The thick gloves didn’t fit into any trigger guards, regardless of trigger style. Glock, 1911, HK, Sig (flat or curved). But with everything but Glocks I was able to get enough trigger finger in there to pop the snap cap. Glocks I couldn’t get my gloved finger on the little dongle so firing was problematic.

I always knew there was a reason I kept my old USP full size and compact around.. When in cocked and locked configuration or SA mode, the trigger is moved further rearward to allow for more glove space - not to mention the generous size of the trigger guard.. The USP remains my favorite winter carry.

FWIW, I decided to compare your results with a Glock with my Shadow Systems MR920 and the dingus Shadow uses is much easier to operate, barely affected by a thick glove. Then I tried my little CZ P-10 S...same thing, easy to operate with the big glove and thanks to a generous trigger guard.

 

[JR24]

I always knew there was a reason I kept my old USP full size and compact around.. When in cocked and locked configuration or SA mode, the trigger is moved further rearward to allow for more glove space - not to mention the generous size of the trigger guard.. The USP remains my favorite winter carry.

FWIW, I decided to compare your results with a Glock with my Shadow Systems MR920 and the dingus Shadow uses is much easier to operate, barely affected by a thick glove. Then I tried my little CZ P-10 S...same thing, easy to operate with the big glove and thanks to a generous trigger guard.

Hmm, didn’t try the HK45c with the hammer back, I bet that would help some and yes, I recall my P07 having a quite generous trigger guard, and I think the P10 seemed pretty similar.

I do kinda miss that P07 a bit from time to time now that I actually know how to shoot a DA/SA half decent.

 

[Alllen Bundy]

The rough trigger linkage bar is the main reason for a gritty trigger on a new Sig P365 series pistol. Here are the photos of the trigger bar where it contacts the sear and the striker safety lever before and after being polished




I initially used a diamond whetstone to perform the hand grinding, and then I wet sanded with silicon carbide sandpaper to smooth out the grinding marks.

Can you say SMOOOOTH trigger? I thought you could.

 

[Alllen Bundy]

You can replace the trigger with no more fancy tools than a round toothpick with the pointy ends cut off and a paper clip with one end straightened if need be.

If you have a manual trigger safety, place your thumbnail over the detent stop so that the detent can just ride over your thumbnail over the detent stop as you rotate the manual safety lever on the left side clockwise. Rotate the lever further clockwise until you can pull the lever outward and then you can lift the safety lever out of the FCU. Set it aside and don't lose the detent and detent spring.

Use your thumbnail to hook underneath the trigger bar return spring. While holding the trigger forward, press the spring tang inward and out of the hole in the trigger linkage bar.

Now lift the end the trigger linkage bar out of position. You will not be able to remove it from the trigger yet.

Slide the disconnector out of the FCU.

Use a pushing device (toothpick, punch, wire) through the lower of the two holes that you exposed by removing the disconnector, push the striker safety lever pin outward just far enough to remove the takedown safety bar, while holding the pusher in place, and then push the striker safety lever pin back inward so that the striker safety lever does not fall out of position.

Rotate the takedown lever far enough clockwise until you can pull out the takedown lever.

Use a pushing device (thin punch, wire, needle) push out the trigger pivot pin. It's a very loose fit.

Lightly lift the trigger linkage bar outward as you pull the trigger and the trigger linkage bar will disconnect from the trigger.

Move the trigger forward and it will come out of the FCU.

Now is a great time to polish the trigger linkage bar where it contacts the sear and striker safety lever.

Clean all of the parts, lubricate, and reassemble in reverse order. When you get to the point where you are ready to reinstall the takedown safety bar, only push the safety lever pin outward just far enough to sneak the takedown safety bar back into position while keeping the pushing tool in place so that the striker safety lever does not fall out. Then push the striker safety lever pin back in place.

If you have any problems with reassembly see the Sig Guy's videos on YouTube.

SIG Sauer P365 COMPLETE disassembly. Part 1 of 2 - by Sig Guy - May 7, 2021


SIG Sauer P365 complete reassembly. Part 2 of 2 - by Sig Guy - May 7, 2021


You might also want to completely disassemble the FCU, clean and lubricate it. The only thing that is really tricky to reinstall in the FCU is the sear spring, and Sig Guy will show you how.