Testing a comp on a 9mm (data! science!)

[Jayne]

That small comp on the new sig p365x-whatever got me to wondering, just how effective is a little comp? I've seen how well they work on major power factor race guns running rounds with a lot of gas to play with.

I wanted to see what the impact would be with regular 9mm that doesn't have all that gas to play with.

The test mule was a poly80 with a PSA slide, chosen because I wanted to test it's function (100%, happy about that).

I tested 3 ways:

1. nothing added
2. a 2 chamber eBay special comp
3. a sig dot plate mounted on the rail

The 3rd test was to try to rule out just the weight of the comp on there helping. The comp weighs 27g, the optic mount weighs 26g so close enough.

Ammo was some standard velocity 9mm 115gr, and Silver Bear 115gr +P+. It's HOT, runs over 1300 fps out of my G34. If anything would have some gas, it would be that.



Drill was just 5 rounds fired an at USPSA target at 8 (or maybe 10, didn't measure) yards, requiring all A zone hits. Over the course of 12 runs I dropped 1 legit C and had one on the perf (there was no RO to make the call) but we're going to say that they're all good hits just to make it easy.

I ran two strings of each ammo with each device.

The draw/first shot has nothing to do with the device, so I just focused on the split times:



What's odd was the weight test runs. I kept saying the gun felt 'funny' when recoiling, and that made it a few ticks slower. Could have just been in my mind.

Watching the slow motion video, the comp does make the smoke cloud spread out and you can see the muzzle flash easier inside the comp vs. in the open air, so it is doing something, even if it's just making things look cool.

Anyway, I'll leave you to draw your own conclusions on how effective a mostly open comp would be on a 9mm using standard pressure ammo.

Unrelated, now I see how much my G34 is helping in SSP. My splits are clearly slower across the board with the poly80 G19 sized test mule.

 

[georgel]

The one issue I would have with your test, is that you selected an unknown eBay Special comp instead of a known and recommended comp. Like flash suppressors, they may look all look alike, but some may work better than others, based on chamber and port design.

Just sayin'...

 

[Get Off My Lawn]

Go back to square one, you need a brass compensator.

 

[Jayne]

Just sayin'...

Yep, it's not a best case sort of test at all. For my new sig wondering the G19 sized gun is too big/heavy and isn't a direct comparison and obviously the comp isn't the same.

It's why I left off any conclusions as to how effective any other comp might be along with the new sig 365 comp edition. It's smaller and more open than the one I picked, so maybe they're working some serious magic to make the physics work, or maybe they're working some serious marketing to make that irrelevant.

 

[georgel]

Also, I believe a tuned comp will utilize a change in recoil springs.

I'm curious about this one...
The Griffin Micro-Comp

Griffin Armament Micro Carry Compensator 9mm 1/2-28 Thread SS Nitride

The Micro Carry Comp was developed to provide concealed carry gun owners with enhanced recoil mitigation and muzzle control without unnecessary weight...

www.midwayusa.com

Special one for G43 and P365...

Griffin Armament Micro Carry Compensator Special Glock 42, 43, Sig

The Micro Carry Comp was developed to provide concealed carry gun owners with enhanced recoil mitigation and muzzle control without unnecessary weight...

www.midwayusa.com

 

[Jayne]

Also, I believe a tuned comp will utilize a change in recoil springs.

Saw some of that for sure.

Looking at test results like these:

Pistol Compensator: Clash of the Carry Comp

We expect to see a pistol compensator on the competition field, and when the Roland Special became popular, they breached into CCW handguns.

www.recoilweb.com

https://pistolwizard.com/guides/barrel/compensator

10 Best Pistol Compensators [Guide]

Want to reduce some recoil? How about tossing on a pistol compensator to your favorite handgun? We take a look at some options you might want to consider.

www.pewpewtactical.com

2018 King of Pistol Comps - Glock Compensator Review - Omaha Outdoors

I have until very recently avoided compensators on pistols. This was for a variety of reasons, most of which were based on my perception of them as being unnecessary for the way I intended to use handguns: as carry and defensive arms. I have for a long time perceived them as only useful on...

www.omahaoutdoors.com

I see lots of claims of "x% less recoil" and "y% less muzzle rise" and some (nice) high speed photography, but not a single bit of data on how it actually changes split times. Lots of "my shots felt faster" and "easier to get back on target" but not a single piece of actual data to back that up.

Where is that data? Where is a "put XYZ comp on and it reduced split times by 10%" result?

There would have to be different classes of shooter as well. As a B class maybe I can't take advantage of the rise reduction, I'm not fast enough to make it make a different. So have a C, A and GM class shooter in the test, maybe 10% rise reduction lets the GM go faster but does nothing for the C class guy.

 

[AR10ShooterinNC]

I see lots of claims of "x% less recoil" and "y% less muzzle rise" and some (nice) high speed photography, but not a single bit of data on how it actually changes split times. Lots of "my shots felt faster" and "easier to get back on target" but not a single piece of actual data to back that up.

As long as it "feels" faster, it's good to go...LOL

 

[georgel]

As long as it "feels" faster, it's good to go...LOL

No, it's got to look good too. What good is it if it doesn't look cool?

 

[LesBaer45]

I haven't seen the Sig 365XL macro comp in person yet. Is it just "comp" slots cut in the slide and the gas goes down / around the front of the frame on the polymer? Or is it a total metal 'comp' and I am just not seeing the front of the slide because it fits so tight into the comp section? Did they put some sort of metal under the front of the barrel/comp if it's not?

Barrel slots under the comp slots maybe?

Just trying to figure out where all of the hot gas is going. I'm not looking to get one but I do like the way they integrated it into the slide looks wise.

 

[JRV]

The Sig setup on the 365XL is the same thing as one of those old-school Wilson bushing comps.

I.e., there’s so much excess bore-through to fit the outer diameter of the barrel that it’s not a comp. There’s no expansion chamber forcing expanding gasses up or sideways, because there’s plenty of room around the bullet for gasses to expand forward.

Porting or a true comp (KKM, Parker Mountain) with a tight bore and expansion chambers is vastly more effective. You need substantially all the expanding gasses trapped behind the heel of bullet being forced somewhere other than “out and around the bullet” for a compensator to, well, compensate, prior to the heel of the bullet leaving the muzzle/last baffle.

The Sig “slide-comp” cannot trap gasses, so it’s somewhere between woefully-inefficient and non-functional. You’ll SEE smoke/flame going up through the ports in countless shill videos, but it’s not actually compensating because too much of the gas can go forward.

There’s a reason the KKM and PMM comps look the way they do—like slightly scaled-down versions of the comps on IPSC/USPSA race guns. If bushing comps and “micro comps” (chamberless single-port muzzle brakes on pistols) actually worked worth a hoot, they would have been implemented in competition at a high level decades ago.

If there is any “recoil reduction” in that Sig model, it’s from the round exiting a shorter barrel with less complete combustion but getting the full recoil-stroke and spring of the XL slide.

 

[11B CIB]

Also, I believe a tuned comp will utilize a change in recoil springs.

I'm curious about this one...
The Griffin Micro-Comp

Griffin Armament Micro Carry Compensator 9mm 1/2-28 Thread SS Nitride

The Micro Carry Comp was developed to provide concealed carry gun owners with enhanced recoil mitigation and muzzle control without unnecessary weight...

www.midwayusa.com

Special one for G43 and P365...

Griffin Armament Micro Carry Compensator Special Glock 42, 43, Sig

The Micro Carry Comp was developed to provide concealed carry gun owners with enhanced recoil mitigation and muzzle control without unnecessary weight...

www.midwayusa.com

I’ve got one of these, came with the griffin barrel I bought

I like it. Hard to quantify it in terms of split times but I shoot warmer hand loads in my matches along with using a slide that’s got weight reduction cuts along the front and it has helped the muzzle flip. Again can’t say it’s by 30% or brought my time down by a quarter second etc but it was enough influence on it that I could tell the comp was working

This was before I swapped the slide for the one with optic and lightening cuts

 

[georgel]

I’ve got one of these, came with the griffin barrel I bought

I like it. Hard to quantify it in terms of split times but I shoot warmer hand loads in my matches along with using a slide that’s got weight reduction cuts along the front and it has helped the muzzle flip. Again can’t say it’s by 30% or brought my time down by a quarter second etc but it was enough influence on it that I could tell the comp was working

This was before I swapped the slide for the one with optic and lightening cuts

Sold!

I like your ranger band. I have one just like it on a rifle grip.

 

[Jayne]

it has helped the muzzle flip. Again can’t say it’s by 30% or brought my time down by a quarter second etc but it was enough influence on it that I could tell the comp was working

So not to be an ass here, but how do you actually know it's helping with anything, flip or otherwise and what's that really doing for you performance wise on the clock? Or, what does "working" mean to you in a performance context?

While shooting yesterday the comp seemed to be doing something, it was making a larger cloud of gas and while writing down the times it was like "yea, that looks like something" but then when I got them all into the spreadsheet, it was a whole lot of nothing. if I had to put money on it before I ran the numbers I would have bet the wrong way.

 

[11B CIB]

So not to be an ass here, but how do you actually know it's helping with anything, flip or otherwise and what's that really doing for you performance wise on the clock? Or, what does "working" mean to you in a performance context?

While shooting yesterday the comp seemed to be doing something, it was making a larger cloud of gas and while writing down the times it was like "yea, that looks like something" but then when I got them all into the spreadsheet, it was a whole lot of nothing. if I had to put money on it before I ran the numbers I would have bet the wrong way.

Perceived recoil. In the way you can tell if you’re running white box or +P, you can physically tell a difference. Same with a rifle; you can tell recoil is reduced when you install a brake without having an actual quantitative percentage applied to it

I can set up a video and remove the comp, fire 5-10 rounds, reinstall, fire 5-10 rounds and see if there’s enough difference in muzzle rise to be visible

Edit: Recoil web already did the work. On a CZ P10C 9mm, average muzzle rise was reduced from 13.99 degrees to 8.3 degrees (which is excellent for basically a thread protector with ports) but noted blowback from the open ports when firing from close retention. A larger comp typically showed more reduction (KE Arms was 57% versus the Micro comp of 41%) but the drawback to the larger comps are clearly the size and need for perfect timing

 

[Cole_McD]

That Griffen micro comp is very interesting, especially if it works.

I have a Primary Machine comp on one of my handguns and it absolutely works, even with lightly loaded factory ammo like blazer brass... though it's more obvious with +P ammo. I do feel like this kind of thing is likely incredibly different to quantify. I'd think muzzle rise may be a better way to quantify the effectiveness as opposed to split times.

IME, split times on comped pistols vs non-comped pistols doesn't change much in a static environment, however the ease of performance on demand certainly does.

 

[NCFubar]

Where you getting all this 9mm ammo to conduct these experiments? Did you find a loaded down white van selling it buy the case dirt cheap in the RDU area?

… and I’m not a cop just wondering … 🤭

 

[Jayne]

Perceived recoil. In the way you can tell if you’re running white box or +P, you can physically tell a difference.

Agree with that, I can tell the standard vs. the +P+ stuff by feel. I also know the actual speed delta of the 5 round drill when shooting the standard and the +P+, it's quantifiable beyond feel.

Edit: Recoil web already did the work. On a CZ P10C 9mm, average muzzle rise was reduced from 13.99 degrees to 8.3 degrees (which is excellent for basically a thread protector with ports) but noted blowback from the open ports when firing from close retention.

I don't measure speed/accuracy by degrees of muzzle rise. They're providing exacting numbers on something that's related to performance but not actually performance.

Now it could be that non-GM level shooters can't take advantage of that lower climb. At a match I was listening to several GM types talk about oil viscosity and how XYZ slowed the slide down to where it was slowing their splits, they were waiting on the gun to cycle. I'm not good enough to take advantage of the extra time a higher velocity slide would provide, so to me changing oil viscosities would be measurable via some method, but provide no actual performance gains with me driving the gun. Obviously if I was getting paid to shoot and had products with my name on it, would be a different story.

 

[Jayne]

Where you getting all this 9mm ammo to conduct these experiments? Did you find a loaded down white van selling it buy the case dirt cheap in the RDU area?

… and I’m not a cop just wondering … 🤭

$100 a case for WWB seems reasonable so I bought a few from the guy. His van was pretty nice, I gotta say I'm a little jealous.

 

[11B CIB]

Agree with that, I can tell the standard vs. the +P+ stuff by feel. I also know the actual speed delta of the 5 round drill when shooting the standard and the +P+, it's quantifiable beyond feel.



I don't measure speed/accuracy by degrees of muzzle rise. They're providing exacting numbers on something that's related to performance but not actually performance.

Now it could be that non-GM level shooters can't take advantage of that lower climb. At a match I was listening to several GM types talk about oil viscosity and how XYZ slowed the slide down to where it was slowing their splits, they were waiting on the gun to cycle. I'm not good enough to take advantage of the extra time a higher velocity slide would provide, so to me changing oil viscosities would be measurable via some method, but provide no actual performance gains with me driving the gun. Obviously if I was getting paid to shoot and had products with my name on it, would be a different story.

You’ve got to use the percentage of muzzle rise reduced as a starting performance point because the seller can’t guarantee split time reductions or specific speed increases. Sort of like selling a suppressor: they can tell you how big it is and how many decibels it’ll reduce the shot by but they can’t 100% guarantee tighter groups or a tone that’s pleasing to everyone.

For example, It took me a long time to get used to a pistol red dot versus using competition irons, from drawing and acquiring the dot vs the sights, the same way it would take getting used to a pistol shooting a particular power factor to suddenly having half the muzzle rise it previously had. I would be overcompensating my push back to target as I manage the pistol through its recoil to reacquire my sight picture, as muscle memory from thousands upon thousands of identical uncompensated rounds dictate a certain response I now have to adapt.

Not being instantly better with one comp doesn’t really surprise me given the vast amount of them on the market and the variety of performance offered.

 

[Sleazy P. Martini]

In my experience, the Griffin comp is a glorified thread protector and I say that as someone with one on their carry gun. It protects my EZ-Lok threads though, so it makes it worth it.

I had a brief fascination with comps about two years ago. I bought a Zev Comp V2 and used it in conjunction with the old 3N38 147 gr. load. For the uninitiated, the 3N38 load is very hot and was recently removed from V-V's load data (thanks, in part, to yours truly). Anyways , the Zev Comp V2 and that 3N38 load was a work of art. It turned a handful of a 9x19 load into a very soft shooter. I would guess a 50% reduction in felt recoil. The only downside is it gave me a splitting headache after a magazine or so from the concussion.

There are certainly applications for comps, but I wouldn't want a *real* comp on a carry gun, but YMMV.