6.5 can for 223?

2aBaC̶a̶

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Whats your guys take on using a slightly larger caliber cans for 223/5.56 to reduce gas blowback at the sacrifice of a few db?

Because I cant afford a can for every gun Im thinking of getting a 6.5 can that I can use on my bolt guns but will mostly live on my 5.56.
 
It will be fine just so long as the construction permits the pressure. It will be a little louder but with 223 especially in an AR you will need hearing protection anyway.
 
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My 30 cal rugged razor has never been used on a 30 cal gun. It's very pleasant/low back pressure on an AR-10 in 6.5 and a stack of AR-15s in 223 though. Am I leaving some DB reduction in the table? Certainly. But it takes the edge off and makes shooting more enjoyable for me. I've got enough hearing problems as is, so I always wear ears anyway.
 
I rarely wear ear pro when I’m shooting suppressed or the guys I’m shooting with with are using cans too. That said, i have some hearing damage and tinnitus that i acquired before i started shooting as much as i do now.

Also, i used to run a Ultra 7 .30 on my 18” AR. I recently added a Ultra 7 .264 to the collection and now it gets used on the same AR instead of the .30… i have noticed no additional gas to the face but it is noticeably quieter than the .30 was.
 
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Cans like the Helios use a near 36 bore size as a back pressure mitigation technique, even on 223 specific designs.

Most the 6.5 cans on the market are specifically designed for bolt guns with no concern for back pressure.

My advice is to do your homework on pewscience.

There's plenty of 30 cal options that do it all pretty okay, but in the end a can per rifle is really sweet.
 
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I run my .30 cal SAS 9" on my 16" AR. But I treat the thing like a bolt gun and have only ever "mag dumped" once (to check for reliability :)). An SLR adjustable gas block is your friend and I suspect an 18" rifle gas barrel would make it even friendlier.
 
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If it's your first can and you're not sure you want to spend a ton, I'm very happy with my YHM Resonator for a bolt action in 6.5. You can swap the mount out later if you invest in another brands mounts as well.
 
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You can offset some backpressure/blowback with a suppressed carrier (Bootleg, GemTech) and properly tuned gas system.

I run my Omega on my DMR all the time and it runs great. No gas in the face.
 
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I’d go 30 cal can as well. Or something like a SilencerCo Omega 36M. You won’t notice the sound difference due to the gas exiting the receiver. You will however notice the lack of back pressure and tuning issues with a larger can
 
I have been using a Saker 7.62 on my 5.56 for a few years. You can put a 5.56 end cap on it, which will supposedly quiet it down even more. I have a 36M too that I use on my 338 but I’ll bet it would work fine on a 5.56. Silencerco has testing data on their website and all of their larger cans are tested on the 5.56. The main benefit to using a dedicated 5.56 can is the smaller size.
 
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Good to hear, thanks for all the replies.

I currently have a 30cal Rex Silentium thats been waiting since April. Im thinking it will mostly live on the 300PRC which got me thinking I should probably get another one started that can swap for the smaller calibers. 5.56s and 6.5s.