Sig 365 Ammo, Should You Care?

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Sig 365 9mm Ammunition in 115gr FMJ and V-Crown JHP

I've long advocated the importance of understanding the compromise we make when we select a 9mm carry pistol with a barrel under 4" in length. Handguns are a compromise to begin with, giving up power (for lack of a better word) in the name of convenient transport. Because we are not at war, we carry firearms just in case. Just as we wear setbelts, not because we plan on a car wreck, but in case of one.

This Article is the result of an intent to test Sig 365 Ammunition. The test process included setting a base line for ammunition performance from a standard 4" barrel and a 3" barrel as commonly used in defensive handguns. We looked for consistency between range and defensive loads, as well as testing the ammunition from non-Sig firearms. Information about the firearms can be found beneath the ammunition data.

SAAMI, the Sporting Arms & Ammunition Manufacturing Institute was founded in 1926 to help standardize firearms and ammunition manufacturing. SAAMI is how we know exactly what a particular cartridge is, and manufacturing to their specifications is what helps protect us from a firearm exploding or failing when said cartridge is put into a firearm marked for that cartridge. In addition to sizes and pressure, one of the standards is a range of velocity as measured from a test barrel. The test barrel length for 9mm per SAAMI is 4" in length with 6 groove rifling and 1:10 right hand twist. You're welcome to see these specifications yourself on page 130 of SAAMI Z299.3 - 2022. In short, 9mm ammunition is generally loaded to perform to standard from a 4" barrel. When the barrel is shorter than 4" the projectile might not reach the inteded velocity and may not perform as intended. In the case of a hollow point that means not hitting the target fast enough, with enough energy for the hollow point to open.

Sig's 365 ammunition is labeled as optimized for performance in short barrels.

What about all the little guns? Fortunately, some ammunition manufacturers have gone to the trouble to either develop a projectile that can perform at lower speeds, or have adjusted the powder to give the projectile more speed from a shorter barrel. This is what made "+p" ammunition popular in the past as a means of compensating for shorter barrels. Yes, SAAMI has guidelines for +p ammunition also. You can find that information HERE.

To Demonstrate what kind of loss there can be found, two control loads were selected from our 23 Load 9mm 115gr Range Ammo Test. Since projectile weights are the same, powder burn rate and amount of powder would be the biggest variable so the second "hottest" and second "softest" loads were selected (I was out of the absolutes) and chronographed through a 4" and 3" barrel to serve as a control reference. Information about the firearms used can be found below the ammunition information in this article.

Control Test results using Winchester Active Duty, Fiocchi 9AP, and Sig 365 through 3" and 4" barrels. Velocity measured at target 7 yards from muzzle.

Energy and Velocity Loss for the 365 Ammunition is irrelevant as the ammunition is intended to perform from shorter barrels, but as you can see, we can conclude about a 10% loss in energy by stepping from a 4" barrel to a 3" barrel. Returning to our seat belt analogy would you be comfortable getting into a car crash if your seatbelt was only going to do 90% of it's job?

The energy is effectively how hard the projectile hits the target and is a vital part of ensuring a hollow point opens and does it's job. Testing Sig's 365 V-Crown Hollow points for performance in gel was time and resource prohibitive, and no matter how a gel test is done it's never a guarantee to represent real-world application as every defensive shooting scenario is different. What we could test fairly was the 365 FMJ against the 365 V-Crown JHP to see if they performed similarly enough to make training with the FMJ representative of the more expensive V-Crown JHP.

Sig 365 FMJ vs V-Crown JHP fired from a Sig 3" barrel and measured at 7 yards.

From this small sample size we can conclude that, in a rare instance, the defensive ammunition is slightly "softer" than the range ammunition. If true, I find this to be a good thing as it means the pistol will be more mangable during a stressful defensive situation than it is on the range in training. What we must assume is that Sig's V-Crown JHP is intended to open and perform properly from that lower speed. It is nice to see that the defensive ammunition was more consistent than the range ammunition. While shooting (as seen in the video) the V-Crown ammunition recoil impulse felt smoother to me.

Amunition Tested Pricing as of 17MAR24 (click link for current pricing)

Sig 365 115gr FMJ $22.99 / 50 direct from Sig

$28.03 /50 at Palmetto State Armory

$24.59 / 50 at Sportsman's Guide

Sig 365 V-Crown JHP $19.99 /20 direct from Sig

$15.99 / 20 at GrabaGun

Firearms used included the Ermox Defense X-Fire, a Custom Sig 365XL Build, Mossberg MC2SC, Custom 365 X-Macro Build, SCCY DVG-1, and Canik MC9

To Demonstrate fucntion and performance in other firearms a sampling was selected of appropriate barrel length. Note the differences in velocities, all 5-round samples pulled from the same box of ammunition. Differences in velocities can be the result of ammunition inconsistencies, but in this case is more likely the result of different barrel qualities. Chamber sizing, bore sizing, rifling, etc. Results were interesting indeed.

Control 4" Example: Ermox Defense X-Fire w/ Primary Arms Classic Series

Ermox Defense X-Fire with a Primary Arms Classic Series 24mm red dot. Series

This combination produced a metal-framed striker-fired pistol with mounted red dot for under $450! The Ermox Defense X-Fire provides excellent performance contrary to what the introductory pricing suggests. We met with Ermox at the IWA Outdoor Classics 2024 show and they have some other exciting products that will hopefully be on their way to the US soon. The Primary Arms Classic Series 24mm red dot is so basic that it doesn't even have a catchy product name, but for $149.99 it works.

Sig 365 FMJ Performance through the Ermox X-Fire

Control 3" Sig Barrel: Sig X-Macro Custom Build w/ Holosun 507K

Sig 365 X-Macro slide, Tyrant CNC Trigger, Sharp's Bros grip module, and Holosun 507K all to produce the same energy as a standard 3" Sig P365

This highly-modified-looking 365 setup used the slide and barrel from the Sig P365 X-Macro to give us regular P365 3" barrel energy. The Holosun 507K was purchased to find out what all the fuss was about and I'm not particularly impressed. The Sharps Bros grip module widens the grip to 1.3" for compact-gun comfort. This was my first range session with the new Intellifire trigger from Tyrant CNC which provides a safety dingus, but also shortens trigger travel.

Sig 365 FMJ performance fired from the X-Macro build.

Ultra-Affordable SCCY DVG-1 w/Riton Optic

SCCY DVG-1 with Riton Red Dot

The SCCY DVG-1 has a 3.1" barrel and represents an ultra-affordable way to get into the "micro compact" world even though SCCY was making pistols in this size group for years before it became a size group. The Riton optic is far from a personal favorite, but was included with the original offering of the DVG-1. Velocity differences between this pistol and the Sig barrel seen above may suggest a difference in barrel quality of construction technique though such a conclusion would be unfair with such a small sample size of data. A semi-scientific guess would be that the lower deviation but also lower speed might come from a tighter barrel; forcing more complete combustion but also robbing energy through friction.

Sig 365 Ammunition performance through the SCCY DVG-1

A little Longer: Mossberg MC2SC with Viridian Optics RFX15

Theoretically, if all other things are equal the 3.4" barrel of the Mossberg MC2SC should give it a velocity edge. This pistol has been a favorite of ours for its range handling characteristics. The addition of the Viridian Optics RFX15 made shooting extra enjoyable.

Sig 365 FMJ performance through the Mossberg MC2SC

Canik METE MC9 with Viridian Optics RFX11

Canik MC9 with a Viridian Optics RFX11

The Canik METE MC9 is a favorite of Teya's and she's been carrying this model for about a year now. The Viridian Optics RFX11 is Viridian's smallest optic and as such uses auto-adjust to omit buttons. The smaller window feels a bit tight, but the optic also sits nice and low on the Canik METE MC9. The Canik METE MC9 has a 3.18" barrel.

Sig 365 FMJ performance in the Canik METE MC9

Fancy Sig 365XL Build with Sig Romeo-X Compact Optic

This Sig P365XL Build uses a custom-shop slide, Zev barrel, Icarus Precision grip module and Sig's Romeo-X Compact dot.

With a 3.7" barrel the Sig P365XL offers handling closer to a compact handgun. This build uses the discontinued Zev 365XL barrel, a Sig Custom Shop Spectre slide, Icarus Precision grip module, and Sig's new Romeo-X Compact red dot which includes fiber-optic rear sights. We plan on a deeper dive on this new optic in the future. So far I like the dot's advanced feature set for such a small optic. Note that while there was not a velocity gain over the Canik, the standard deviation and extreme spread were smaller indicating more uniform performance.

Sig 365 Ammunition performance with a custom 365XL build.

The Process of this testing can be seen in the video below including how well the groups turned out.

Conclusion: While this test was imperfect, and there is no socially acceptable absolute way to test defensive round performance, we can still draw some valid conclusions from this test.

• It is important to understand the velocity cost of your barrel choice. This includes barrel length and quality.

• While a general rule can be drawn that longer barrels produce higher velocity (to an extent), differences between individual barrels mean that there is no absolute foot-per-second to barrel length rule.

• Different loads exhibit different velocity losses or gains with barrel length changes.

• Sig's 365 Ammunition matches energy and velocity fairly well between V-Crown JHPs and range FMJ.

• Graham does not enjoy math, but math is required for physics.