Shooting 6mm ARC through a 6.5mm or 6mm Suppressor?

phlukefenny

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Good day ladies and gents,

Background: I currently own a 6.5 Creedmoor bolt comp/precision rifle, i do not own a suppressor with it. I am looking to purchase a 6mm ARC precision based semi auto rifle. I would like to purchase a suppressor with it; I have been looking at the KGM R6, KGM R65K, and the KGM R65T. I am unsure if I want to buy a single 6.5mm for both rifles or get separate cans for each rifle. I am worried that purchasing a 6.5mm can is too much of a difference when it comes to precision base shooting compared to the 6mm can, i am also wondering if there may be gas issues between the two. (I am slightly new to suppressors)

Question: Is it worth/important getting the KGM R6 (6mm specific can) and purchase a separate can for my 6.5mm Creedmoor? Or is it best to just get either the KGM R65K or KGM R65T (6.5mm cans)?

I am NOT getting a 30 cal suppressor, although I do appreciate the lovely comments that tell me otherwise lol.

Thank you for all that help!
-Luke
 
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Thanks for the feedback @B Man and @M_R_Woodard . I decided that I will purchase the 6.5 suppressor first and get a 6 down the road.

If anyone has any more input on this, I think it would be very beneficial overall since there are not many conversations about this in the google search from what i can see. It seems that there is very little data that shows how much of a difference there is between an off sized suppressor and a specific suppressor.

Thank you again all for the feedback.
 
I have 22 LR cans and 30 cal cans. The 30 cal cans are for any center fire up to 300 WM, and the others for rimfire.

That way I never fugg up and shoot 6.5 through my 6mm can, or 308 through my 7mm can.

It’s a thing.

People will tell you that you need to have caliber specific cans, but that’s not my experience at all.

You’re overthinking this.

 
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Another option is to use a 556 can provided the bore size is large enough.

I shoot 6ARC through my RC3
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My. 30 cal cans have worked pretty great on .223, 6 ARC, 6 GT, 6.5 Grendel, 6.5 CM, .280 AI, 7 PRC, .308, .30-06 and .300 WSM. If you're new to suppressors and want caliber specific cans you should get them, it might be a learning experience on why you keep getting the lovely .30 cal recommendations though.

Why are you just looking at KGM cans?
 
You're focusing on the wrong thing. Bore size really doesn't matter as long as the bullet will fit. The ejection port noise on your 6ARC is going to make just about any suppressor sound loud to your ears. You should be more concerned with flow rate and back pressure for that gas gun. In fact shooting a .30 cal can on that 6 ARC would help the flow rate. I would think of it as buying a bolt gun can and a gas gun can. Not buying a 6.5mm can and 6mm can.

Suppressors like the CGS Hyperion K and Abel Co. Theorom have solid and vented end caps that help you adjust the flow rate so you can increase or decrease the back pressure. Guess what caliber they are...
 
Unpack this, if you can, using engineering and physics.

"I would look for a smaller volume oriented 300BO can for the ARC. The added size of the 308Win/CM can doesn't yield better suppression."

Silencer Central doesn't agree: "A longer suppressor with more internal volume capacity is going to lower the decibel levels heard by the shooter and those around them by a greater degree than a shorter suppressor with less internal volume capacity."

DOES YOUR SUPPRESSOR LENGTH MATTER? BEST SUPPRESSOR LENGTHS

Again, the reason for just buying a 308 can and stop overthinking this.
 
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Unpack this, if you can, using engineering and physics.

"I would look for a smaller volume oriented 300BO can for the ARC. The added size of the 308Win/CM can doesn't yield better suppression."

Silencer Central doesn't agree: "A longer suppressor with more internal volume capacity is going to lower the decibel levels heard by the shooter and those around them by a greater degree than a shorter suppressor with less internal volume capacity."

DOES YOUR SUPPRESSOR LENGTH MATTER? BEST SUPPRESSOR LENGTHS

Again, the reason for just buying a 308 can and stop overthinking this.
The only possible counter is that smaller cans will hold less pressure and create less noise at the ejection port than a longer, high back pressure can. Assuming we are talking about a gas gun…
 
Unpack this, if you can, using engineering and physics.

"I would look for a smaller volume oriented 300BO can for the ARC. The added size of the 308Win/CM can doesn't yield better suppression."

Silencer Central doesn't agree: "A longer suppressor with more internal volume capacity is going to lower the decibel levels heard by the shooter and those around them by a greater degree than a shorter suppressor with less internal volume capacity."

DOES YOUR SUPPRESSOR LENGTH MATTER? BEST SUPPRESSOR LENGTHS

Again, the reason for just buying a 308 can and stop overthinking this.

Silencer Central is not the authority I would hang my hat on. If I made junky inefficient large silencers I'd probably try to convince you that you needed a junky inefficient large silencer. There are diminishing returns with volume, not to mention efficiency.

You often hear on forums to just buy a universal .30 silencer. Unfortunately then you get to find out the hard way there's a reason 223 silencers exist. Less is sometimes more.
 
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I'll sit back and wait for you to post links arguing the contrary, based on empirical evidence or engineering calculations.

You were not arguing why there are 223 cans, you stated that more volume does not equal less noise, all things being equal.

More volume does equal less noise.

Again, using physics, please detail the basis in fact for this comment, "There are diminishing returns with volume, not to mention efficiency."

The only "diminishing return" might be larger volume is heavier and bigger in size. By efficiency do you mean greater DBs of noise reduction per unit volume? Per unit weight? Inquiring engineers want to know.
 
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Take two high back pressure suppressors of equivalent design, the difference bring overall length. The Q Thunder Chicken and Trash Panda would be emblematic. On a bolt gun, one would expect the higher volume can to be quieter at the muzzle and at the shooter’s ear.

But on a gas gun, it is possible that the shorter can will meter quieter at the shooter’s ear. This would be because the lower volume can will hold less gas pressure to be released through the ejection port as the gun unlocks.
 
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Take two high back pressure suppressors of equivalent design, the difference bring overall length. The Q Thunder Chicken and Trash Panda would be emblematic. On a bolt gun, one would expect the higher volume can to be quieter at the muzzle and at the shooter’s ear.

But on a gas gun, it is possible that the shorter can will meter quieter at the shooter’s ear. This would be because the lower volume can will hold less gas pressure to be released through the ejection port as the gun unlocks.
All things are not equal though. Of the two cartridges listed by the OP, one has 16 grains less propellent capacity. 300 Whisper/BO and 223 silencers are generally smaller than 308 Win for a reason. Yeah, you can buy 9" long silencers that sound awesome. They are also 9" long. When you start getting into the 7" lengths, purpose built caliber specific cans are generally smaller and sound better than the generic 308 Win can. Not to mention the smaller cans are just...smaller. The market is known anyone can freely look for themselves.

Not that any of this really matters, OP listed out what he's looking for in a way that suggests his mind is made up. 6mm is kind of niche outside of over bored 223.

You were not arguing why there are 223 cans, you stated that more volume does not equal less noise, all things being equal.
David, the only one arguing is you. If you don't like my post feel free to give your own opinion and move on. I never stated "all things being equal" either. My opinion does not involve all things being equal, quite the opposite.
 
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Unfortunately then you get to find out the hard way there's a reason 223 silencers exist. Less is sometimes more.
No less is never more. Bigger cans work better, going smaller is a trade. Larger bore cans are more versatile then smaller bore cans. Companies that make silencers would love for you to purchase a .22 caliber can, a 5.56 can, a 6mm can and a .30 caliber can. It is a money maker for them.
 
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I screwed my TBAC 338 Ultra on my 7.5" 300BO to wow myself with an extremely quiet subsonic 300BO PDW. I was definitely wow'd. It was barely any quieter than the Rex 8 baffle MG7(6.5" long). I thought it was going to be amazingly quieter. On my 16-in barrel 300 blackout it is. It's a huge difference between the 338 Ultra and an ultra 7. But on a gas gun I couldn't even barely tell the difference. If somebody made me a bet before I tried that about how quiet I thought it would be, I would have made that bet and lost a bunch of money. I am sure with some technical equipment the metrics would look impressively different between the two cans, But by ear it was barely noticeable. The ejection port noise masked everything
 
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I do not have a KGM can so my experience for this topic is limited (since the OP is being specific on brands). I haven't noticed my Polonium being quieter than my Nomad 30 on my one 6mm ARC being shot back to back. My shooting buddy said the tone is different and both are quiet (scientific it is not). For me behind the thing, they sound the same and naturally the Polonium likes to add some gas to the face even with some tuning but it's not unlivable. The Nomad 30 is easier to live with as far as gas in the face is concerned. No surprises there at all and everyone that has a 30 cal and 6mm cal (probably have to be larger bore 223) can knows.

I typed the above to state for the OP that a 30 caliber can is going to be the most versatile option. It seems his only option staying with the intent of his question is individual cans per rifle (or get the larger bore and roll on). That isn't a bad idea either.

Why KGM? You live next door, first cousin is the Manager, got a coupon, etc. Not bad mouthing them as I have zero experience there, but they are not usually mentioned when a comparison is conducted. I haven't searched their products so I am genuinely curious why someone would be adamant about wanting one.
 
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I do not have a KGM can so my experience for this topic is limited (since the OP is being specific on brands). I haven't noticed my Polonium being quieter than my Nomad 30 on my one 6mm ARC being shot back to back. My shooting buddy said the tone is different and both are quiet (scientific it is not). For me behind the thing, they sound the same and naturally the Polonium likes to add some gas to the face even with some tuning but it's not unlivable. The Nomad 30 is easier to live with as far as gas in the face is concerned. No surprises there at all and everyone that has a 30 cal and 6mm cal (probably have to be larger bore 223) can knows.

I typed the above to state for the OP that a 30 caliber can is going to be the most versatile option. It seems his only option staying with the intent of his question is individual cans per rifle (or get the larger bore and roll on). That isn't a bad idea either.

Why KGM? You live next door, first cousin is the Manager, got a coupon, etc. Not bad mouthing them as I have zero experience there, but they are not usually mentioned when a comparison is conducted. I haven't searched their products so I am genuinely curious why someone would be adamant about wanting one.
I haven’t seen much in the way of their objective suppression testing either.

I see people mention KGM a lot, I read they do primarily military runs and consumers get a lot less of their overall volume of product.

I’m naturally skeptical in any government procured product. It’s rarely a “best performance for the use case” as government procurement and bidding is very nuanced, and cost driven.

Outside of the Facebook 6 arc groups, it rarely gets mentioned.

Similar to Rex Sentilium stuff. Seems to work for many for the price, but rarely spoken of as “top performing”, and to be honest with you, there’s a lot of fanboy bias in this industry.

Most people don’t ever see enough suppressors, or try them first hand, to compare performance anyway.
 
I haven’t seen much in the way of their objective suppression testing either.

I see people mention KGM a lot, I read they do primarily military runs and consumers get a lot less of their overall volume of product.

I’m naturally skeptical in any government procured product. It’s rarely a “best performance for the use case” as government procurement and bidding is very nuanced, and cost driven.

Outside of the Facebook 6 arc groups, it rarely gets mentioned.

Similar to Rex Sentilium stuff. Seems to work for many for the price, but rarely spoken of as “top performing”, and to be honest with you, there’s a lot of fanboy bias in this industry.

Most people don’t ever see enough suppressors, or try them first hand, to compare performance anyway.
Well said! No doubt about the fan boy attitude too. I'm a fan boy of OCL, Diligent Defense, my Nomad 30, and eventually a lot more brands. Who knows, a KGM can may eventually make me spend another $200 and wait a while. I'm probaboy just a suppressor slut and don't realize it.

When I first read the thread and saw where specific suppressors were mentioned I kind of thought the OP had already answered any question he may have had. The only real question was "do I buy the blah blah 6.5 can or buy one of each caliber blah blah cans". The only answer is of course, to buy one of each caliber blah blah cans. Who wouldn't???
 
The 338 Ultra is why the best .223 can isn't a .223 can
For a fact, I have a older SRT Arms Hurricane TI I bought in 2012. It's 223 specific and for the time it was made pretty damn light.... it lives on a 17hmr and everything else wears some sort of hard use 30 cal can for the most part.

The car guys call it no replacement for displacement, cans are no different.
 
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For a fact, I have a older SRT Arms Hurricane TI I bought in 2012. It's 223 specific and for the time it was made pretty damn light.... it lives on a 17hmr and everything else wears some sort of hard use 30 cal can for the most part.

The car guys call it no replacement for displacement, cans are no different.
Forced Induction displaced that theory.
 
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I have a KGM R6 on my 6ARC and the only reason I have it is because it was stupid cheap and it was an extra can I had when I built my ARC. I would not buy a 6mm dedicated can again. 90% of my cans are .30 and I run them from 300PRC down to 22ARC. I hate having a couple .22Cal cans mixed in and I have to make sure I don’t put a .22 can on something bigger.
 
Forced induction solvent additive port? Noiceeee
I plan on adding a 3 port manifold with a magneto speed ratchet strap. One port to drive the rifle gas, one to make a little train smokestack go Tweeet! Tweeet!, and one for future expansion. Like maybe if a nearby shooter needs a gas source.
 
Sequential suppressors is what you are refering to. Question I have is do you attach more barrel to the front of the first smaller suppressor or just use a larger than bore diameter tube between the suppressors?

I believe the first suppressor will have to be small and gassy to help spool up the larger second suppressor. I suspect a set up like this would be a paradigm shift in noise reduction and if made as a unit would only require one $200 extortion. I bet the actual sound signature would be kind of like when you have diarrhea and you have all that gas before you blow out the plug. Guys on the line would look around wondering who just shit their pants. This thread has gone off topic and I was glad to help.
 
Sequential suppressors is what you are refering to. Question I have is do you attach more barrel to the front of the first smaller suppressor or just use a larger than bore diameter tube between the suppressors?

I believe the first suppressor will have to be small and gassy to help spool up the larger second suppressor. I suspect a set up like this would be a paradigm shift in noise reduction and if made as a unit would only require one $200 extortion. I bet the actual sound signature would be kind of like when you have diarrhea and you have all that gas before you blow out the plug. Guys on the line would look around wondering who just shit their pants. This thread has gone off topic and I was glad to help.
OP made his decision and abandoned this orphan thread a week or two ago. We are just having our way with someone's bastard right now.