Rifle barrel length question

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macro
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Rifle barrel length question

Post by macro »

I was curious if, and how much, barrel length matters in decibel reduction?
A friend of mine was asking if chopping his barrel down from 26" to 20 or 22" would make a difference in the Db reduction of a .308 rifle?
He just ordered a .308 suppressor and has to get his rifle threaded but was thinking if there was no sound reduction benefit to keeping his barrel at 26" he was going to shorten to 20" or 22". He likes to shoot out to 1000 yards and likes the 26" barrel, but doesn't really want to be lugging around a 26" heavy barrel with a 10 inch suppressor on the front of it if it's not going to make a noticeable difference. I tried a search but couldn't find the answer to it. Any Help would be appreciated.
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yamatitan
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Re: Rifle barrel length question

Post by yamatitan »

It does make a difference but personally the shorter length outweighs the better suppression. Its really just a opinion and I would tell your friend to try and demo a shorter one of possible so he can make his own decision.
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JasonM
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Re: Rifle barrel length question

Post by JasonM »

With 5.56 as an example, I don't notice a huge difference until you get into SBR territory-
going from 20 to 16 isn't a big difference, but going from 16 to 11.5 is a noticeable change...

But like yam said, a supersonic rifle is going to be loud no matter what, so the shorter length, better balance, slightly lighter weight are worth the slight increase in sound.
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macro
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Re: Rifle barrel length question

Post by macro »

Thanks for the replies. Ill let him know.
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JohnInNH
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Re: Rifle barrel length question

Post by JohnInNH »

JasonM wrote:With 5.56 as an example, I don't notice a huge difference until you get into SBR territory-
going from 20 to 16 isn't a big difference, but going from 16 to 11.5 is a noticeable change...

But like yam said, a supersonic rifle is going to be loud no matter what, so the shorter length, better balance, slightly lighter weight are worth the slight increase in sound.

14" to 20" is a huge difference and that's why we have the entire 5.56 SNAFU with twist and bullet weight changes .. the SP1 worked and a chopped M4 does not. (at 55 gr)

Hence the need for the BLK or 6.5 MPC
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Stout
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Re: Rifle barrel length question

Post by Stout »

Actually, the barrel length can have a significant effect on noise. I've seen hunters shooting these Metrogun shotguns in the city limits and they don't make any noise. It's essentially a 36" barrel extension that allows all of the powder to burn in the barrel. Figure 28" factory barrel plus 36" extension for 64" of noiseless fun. Here's the link to website. They explain how it works.

http://www.metrogun.com/

Also, my kids and I shoot the 22 LR CB Caps in my back yard. These are the primer only 22 bullets. From a pistol they sound like a regular 22. From a 16" 10/22 they are noticeably less noisy but still go Bang. From a 26" bolt gun you have to look down the barrel to make sure they came out. And most of the time they do. But the difference is quite amazing.

I bit off the 308 topic but worth considering someday.
RyanB
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Re: Rifle barrel length question

Post by RyanB »

JohnInNH wrote:
JasonM wrote:With 5.56 as an example, I don't notice a huge difference until you get into SBR territory-
going from 20 to 16 isn't a big difference, but going from 16 to 11.5 is a noticeable change...

But like yam said, a supersonic rifle is going to be loud no matter what, so the shorter length, better balance, slightly lighter weight are worth the slight increase in sound.

14" to 20" is a huge difference and that's why we have the entire 5.56 SNAFU with twist and bullet weight changes .. the SP1 worked and a chopped M4 does not. (at 55 gr)

Hence the need for the BLK or 6.5 MPC
I asked some friends at the Ranger Batt and they told me up close they can't tell the difference between 7.62 and 5.56. Works for me.
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