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Is Your Rifle More or Less Accurate with a Suppressor? by TOM MCHALE

Is a rifle more or less accurate with a suppressor? There's only one way to find out.

Is a rifle more or less accurate with a suppressor? There’s only one way to find out.

Would you rather be quiet or accurate? Do you have to choose between them or do this two concepts coexist like politicians and sex scandals?
Not so long ago, I competed in an F-Class match, shooting at a distance of 800 yards. One thing that stood out was the competitors’ finicky attention to muzzle devices, or more accurately, the lack thereof.
First, F-class allows none, so there’s that. Second, the chatter on the firing line was that muzzle devices like brakes, flash hiders, and suppressors only reduce the accuracy of a rifle. I have no reason to doubt that, but it did get me thinking.
Would my everyday rifle configurations be more or less accurate with a suppressor? These aren’t tweaked out F-Class race guns. I use them for plinking, less-rigid competition, home defense, and denting steel plates.
As an experiment, I decided to compare the accuracy of a couple of rifles outfitted with the standard muzzle device – a flash hider or brake – with the same rifles and ammo geared up with one of my suppressors.
Just to be clear, suppressors can help you shoot more accurately because they reduce the blast, noise, and smooth out recoil. That helps the shooter focus on breaking a perfect shot with less noise and distraction.
What I was looking for here was any “mechanical” impact on accuracy, not my ability to shoot better using a can.
To keep optical and wind error out of the picture, I shot a boatload of five-shot groups in each configuration at 100 yards. Yes, there might be some stabilization differences that show at longer distances, but then I would be adding more weight to other variables like wind and my eyes.
Again to try to minimize some variables, I aimed for “warm barrel” scenarios. After some sighters to get on paper, I alternated rifles to give each a chance to cool back down after each five-shot group. By resting the rifles and taking my time, I figured I would stay in the “warm” range and not run into accuracy issues from some groups coming from cold, warm, and smoking hot barrels.
Let’s take a look at some results.

Masterpiece Arms MPA BA Lite with SIG Sauer OTM Match Grade 6.5mm Creedmoor

OK, so maybe this isn’t an everyday rifle for plinking and home defense, but I like to shoot it. Don’t judge. On the other hand, it’s amazingly consistent. It’s also built from the ground up for pure accuracy. Potentially offsetting factors like weight and semi-automatic operation aren’t going to interfere with its accuracy mission. I had a hunch that this one might just shoot better out of the box before sticking a suppressor on the end but there was only one way to find out.
I used Sig Sauer’s brand new OTM Match Grade 6.5mm Creedmoor ammunition. Based on my previous experience with the accuracy of Sig’s match ammo, I had high expectations. This load with its 140-grain open-top boat tail projectile didn’t disappoint.

Sig Sauer's brand new 6.5mm Creedmoor OTM Match Grade ammo shot like a champ from the Masterpiece Arms MPA BE Lite rifle. This is a five-shot group from 100 yards.

Sig Sauer’s brand new 6.5mm Creedmoor OTM Match Grade ammo shot like a champ from the Masterpiece Arms MPA BE Lite rifle. This is a five-shot group from 100 yards.

I shot a bunch of five-shot groups from 100 yards with only the default muzzle brake in place. As you can see from the photo, this brake is a beast. It’s about the size and weight of a grenade and makes a similar concussion. The Range Officer was convinced I was shooting a .338 Lapua Magnum until I showed him the comparatively small 6.5mm Creedmoor cartridges.
I also shot a bunch of groups after removing Brake-Zilla and adding a SilencerCo Specwar 762 suppressor. Also a quality piece of gear, this can makes a great impact weapon in a pinch. Over the years I’ve had it, I’ve found it to be consistent regarding point of impact shift and consistency.
Here’s what I found.
Shooting in the factory configuration, my overall average group size came out to 0.63 inches with a best five-shot group of just .44 inches. That ain’t shabby, and I have to say I was pleased with the performance of the new Sig 6.5mm Creedmoor ammo. For factory ammunition not sized to a specific chamber, that’s pretty darn good.

The Masterpiece Arms rifle seemed to shoot better without a suppressor.

The Masterpiece Arms rifle seemed to shoot better without a suppressor.

After I added the suppressor, my group size actually increased as I suspected it might on this particular rifle. After all, it’s built just so for accuracy, and monkeying around with weight on the end of the barrel, as heavy as it is, probably isn’t going to help things. My overall average five-shot group size worked out to 0.90 inches with the smallest group of .80 and largest of 1.01 inches at 100 yards.

Perhaps the metric ton weight of Brake-Zilla kept the rifle stable...

Perhaps the metric ton weight of Brake-Zilla kept the rifle stable…

Smith & Wesson M&P 10 Performance Center 6.5mm Creedmoor with Sig Sauer OTM Match Grade

Next, I decided to move to a more “everyday” rifle configuration. In past tests, I’ve found this Smith & Wesson M&P 10 Performance Center model to be a consistent and accurate rifle. I repeated the process, keeping the rifle in the “warm” range while firing all of my five-shot groups from 100 yards.
Because tinkering is fun, I had added a Smith Enterprise Vortex Flash Eliminator to this rifle, so I elected to leave that as the “default” instead of the factory flash hider. My overall average group size with the flash hider installed was 0.98 inches with the smallest group being 0.75 inches and the largest 1.14 inches.
I added the same SilencerCo Specwar 762 can that I used on the Masterpiece Arms rifle and proceeded to burn more Sig Sauer ammo. The overall group size? It was 1.03 inches with a smallest of 0.97 inch and largest of 1.12 inches.
To properly use the words “statistically the same” I would have to burn a few thousand round of ammo, but indications were that this rifle really didn’t care between these two configurations with the Sig Sauer 6.5mm Creedmoor ammo.

Expanded Testing

Being curious, I decided to informally expand my testing a bit on this one. I shot some group using American Eagle’s 140-grain Open Tip Match ammo with and without a Gemtech Tracker suppressor. The Tracker is a lightweight model designed for low-volume hunting applications so I figured I might see some more variance with that. I did. My unsuppressed group average was 1.09 inches while the Tracker suppressed groups averaged out to 1.255 inches.
Hmmm. So this rifle wasn’t as happy with a lightweight can. That didn’t surprise me. Next, I decided to go back to my original “heavy suppressor” configuration and swap ammunition. I had worked up a batch of handloads using the Hornady 140-grain ELD bullets, so I tried those unsuppressed and with the Specwar 762. Unsuppressed, my average group size was 1.02 inches. When I added the suppressor, the average group shrank to .65 inches.

I alternated rifles to keep them all in a "warm barrel" state.

I alternated rifles to keep them all in a “warm barrel” state.

Summary

It seemed there were conflicting results depending on the combination of rifle, suppressor, and ammo. Here’s how it all netted out.

Rifle Ammunition Muzzle Configuration

Average Group Size

Masterpiece Arms MPA BA Lite Sig Sauer OTM Match Grade 6.5mm Creedmoor Factory Brake

.63”

Masterpiece Arms MPA BA Lite Sig Sauer OTM Match Grade 6.5mm Creedmoor SilencerCo Specwar 762

.90”

Smith & Wesson M&P 10 PC Sig Sauer OTM Match Grade 6.5mm Creedmoor Smith Enterprise Vortex Flash Eliminator

.98”

Smith & Wesson M&P 10 PC Sig Sauer OTM Match Grade 6.5mm Creedmoor SilencerCo Specwar 762

1.03”

Smith & Wesson M&P 10 PC American Eagle’s 140-grain Open Tip Match Factory Flash Hider

1.09”

Smith & Wesson M&P 10 PC American Eagle’s 140-grain Open Tip Match Gemtech Tracker

1.255”

Smith & Wesson M&P 10 PC Handload Hornady 140-grain ELD Factory Flash Hider

1.02”

Smith & Wesson M&P 10 PC Handload Hornady 140-grain ELD SilencerCo Specwar 762

.65”

VooDoo Review

So let’s boil this down into some probable explanations and learnings.
First of all, there’s clearly no universal takeaway from this limited experiment. Will your rifle be more accurate suppressed? Maybe. Or maybe not. It all depends on the combination of ammo, rifle, and suppressor.
The whole subject of barrel harmonics and what happens when you add objects of different weight to the fiery end is pure VooDoo. In theory, if the barrel moves in exactly the same way every time you pull the trigger, then precision should always correspond with the overall quality of the bore. Since the MPA BA Lite outperformed the suppressor configuration with its factory brake, I’d assume the smart folks at Masterpiece Arms designed the barrel brake to play nicely together. They certainly do. That might explain why I got larger groups by adding the SilencerCo Specwar with this rifle but smaller ones on a different rifle.
This is pure theory on my part, but I have to think that the suppressor mount will come into play. The SilencerCo Specwar 762 is a rock-solid system, but it uses a quick attach and detach mounting system. The suppressor threads onto the SilencerCo muzzle brake (or flash hider depending on what you choose) and then locks into place. Given that I got better accuracy results with the Silencer attached I have to assume that nothing is moving up front as the bullet travels down the barrel. However, I also have to conjecture that a rigid direct thread mount on a quality suppressor might perform even better. That might have to be a future project for a head to head quick attach versus direct thread comparison using the same suppressor, rifle, and ammo combination.
The Gemtech results have me a little stumped. The Tracker uses a direct thread attach, so it’s solid on the barrel once installed. I wasn’t surprised that it was less accurate. But only because of some general notion of “lighter and less expensive.” Why was it? Perhaps there’s some buffeting business going on as the bullet travels past the baffles. While that expanding gas cloud will be behind the bullet, the projectile is going to be pushing air on its own as it travels through the can. Is there a measurable accuracy impact from that compressed air hitting the suppressor interior? Does a less expensive can have more variance in the baffle construction that interferes with the compressed-air column? Got me. If you have thoughts on the matter, I’d love to hear them.

Lasting Impressions

While there’s not enough data here to prove the issue, I have to believe that quality and consistency of the suppressor itself will have a lot to do with the outcome. If there’s any merit to my buffeting theory, then the absolute consistency of the internal baffles would have an impact on precision shot to shot.
So, the answer is clear. Your rifle might be more accurate suppressed. Or it might not.
For more information about Smith & Wesson Performance Center, click here.

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