Suppressors Barrel length for hunting rifle - can I go too short?

drew_235

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May 22, 2019
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I have a Tikka T3x Lite in 6.5 CM that I am going to have threaded for my suppressor(s) and the current barrel length is ~24". I've done a bit of reading and there doesn't seem to be too much down side to bullet velocity loss if I go all the way down to 18". My question, however, is if I shoot it unsuppressed, is there going to be an appreciable noise/blast difference between an 18" or 20" barrel? I ask because I have read some posts about guys shooting Ruger Ranch rifles with their 16.2" barrels and remarking that the muzzle blast was a bit surprising (maybe they've never fired an AR?). It's quite possible that I'm totally overthinking this since it's a hunting rifle and not a range toy.
 
What muzzle attachment are you using? If I think theres a chance I'll ever shoot a particular rifle without the can I go with a flash hider vs a brake attach. I will say that a 16-18" 308 with a brake is obnoxious. Given equal muzzle devices, I don't think you are going to notice much difference between 18 and 20". Both are going to make your ears ring without a can. I would go as short as you reasonably think you can get away with. Look at the ballistics out to your max range (personally about 500 yards for me, ethics wise) and you'll see theres not much gained by adding 2" of barrel. You WILL notice the extra barrel length 99% of the time you use the rifle, which is when you aren't shooting it.
 
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Direct threads.
I have only ever shot prairie dogs "at distance" (450 yards). The furthest deer I've ever shot was at 75 yards, but elk hunting is on the calendar for next fall. I know this may be blasphemy, but I really can't see myself shooting at large game more than 300 yards away. Maybe I'll feel differently in the future, but that is my theoretical limit for now that I have pulled out of my a$$.
 
Nothing wrong with setting a 300 yard personal limit, more people probably should. Use a quality bullet and ram it into the lungs . Elk are tough but they're not bullet proof. Using a ballistic calculator figure out what remaining velocity you'll have at 300 yards and chop the barrel according the results . For elk I'd recommend bullet impact speed of 1800+ FPS for conventional bullets and 2000+ FPS if using copper bullets.
 
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Just plugging some very generic numbers into the calculator a 143 ELDX only needs a MV of around 2400 to keep necessary velocity for expansion at 300 yards. It would still be going about 2000 fps, which allows for a pretty good margin of error. Even a 16" barrel should easily achieve that. Just some info to digest.
 
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Just plugging some very generic numbers into the calculator a 143 ELDX only needs a MV of around 2400 to keep necessary velocity for expansion at 300 yards. It would still be going about 2000 fps, which allows for a pretty good margin of error. Even a 16" barrel should easily achieve that. Just some info to digest.

I did a bit more research, and even with full copper bullets, it seems like there would be little to lose by having the barrel cut down to 16.25" or 16.5" and there would still be plenty of margin to 2000fps.
 
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Very few off hand shots hunting but we all hunt with 18" + suppressor now. I have 2 at 16.5" and might do another. I have longer guns that I can use elsewhere but at our property with the woods its 200 yards and less. My son just took a nice buck with a 18" 6.5 Grendel. I have taken 3 doe this year with the same.
 
WDM Bell and Ernest Hemingway used 6.5s to great effect despite ballistics similar to the modern 6.5 Grendel. Don’t worry about the short barrel.

I love 6.5's, but WDM Bell predominately used a .275 Rigby and 450/400 NE and Hemingway a Griffin and Howe Springfield .30-06. What they both would say however, is that shot placement is everything. Bell once said that he wired the triggers of his 450/400 double gun together so both would go off when the rear trigger was pulled and that he saw no difference between the 200gr delivered by his .275 and the 800gr delivered by the NE. He said that if the shot was placed will it would die quickly if not, death would not ensue. I digress however as this had nothing to do with the OP's question.

I and my brother have both used 6.5 Grendels on white tail from 12"-18" with no appreciably difference. The 12" 6.5 Grendel with 129 ABLR has an effective expansion range of roughly 700 yards and still carrying ~500 ft. lbs. of energy. I seriously doubt you'll have any issues with the 6.5cm regarding velocity and terminal effect.

Muzzle blast both suppressed and unsuppressed will most assuredly be increased by shortening the barrel. This is simply physics, the "uncorking" pressure will increase and the related sound pressure level as well.

If you have a suppressor how often do you really believe you will be hunting without it? Do you typically hunt in states where suppressors are not legal for hunting or otherwise? I have never been in a tree stand or the brush and wished I had a longer rifle.
 
Probably lose about 25fps per inch. The real answer is that it's easier and more convenient with a shorter stick, but that extra velocity is welcomed when you pull the trigger at any sort of range.

The other part is, once you buy a can, you almost never shoot without it. (except for your carry gun).

I have brakes on almost all my long guns, and move cans over to them when I shoot.
 
Muzzle blast both suppressed and unsuppressed will most assuredly be increased by shortening the barrel. This is simply physics, the "uncorking" pressure will increase and the related sound pressure level as well.

And that is really the meat of my question - would a 16" or 18" barrel get to a point where it is absolutely unpleasant unsuppressed.

If you have a suppressor how often do you really believe you will be hunting without it? Do you typically hunt in states where suppressors are not legal for hunting or otherwise? I have never been in a tree stand or the brush and wished I had a longer rifle.

I was going to say Montana because I thought they were suppressor legal only for varmints, but I looked it up again and I had some bum dope. The short answer is no, I don't think I'll ever get to a point where I'm not using this rifle with a suppressor.
 
And that is really the meat of my question - would a 16" or 18" barrel get to a point where it is absolutely unpleasant unsuppressed.



I was going to say Montana because I thought they were suppressor legal only for varmints, but I looked it up again and I had some bum dope. The short answer is no, I don't think I'll ever get to a point where I'm not using this rifle with a suppressor.

The it sounds like you answered your own question lol. Go as short as you want (legally) it will never be unpleasantly loud suppressed.
 
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The it sounds like you answered your own question lol. Go as short as you want (legally) it will never be unpleasantly loud suppressed.

In my original post, I did remark that I might be overthinking this. The thread did offer up some great data and real world experiences, all of which are pointing me towards a 16.5" barrel. Thank you all for another great discussion. :)
 
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Rem 700 .308 Win 16.5” with a Leupold VX3i 2.5-8 is perfect for a WV woods rifle. Shots rarely extend beyond 200 yards unless you’re on a power line right-of-way or a long field. Typical shots are within bow range. I have killed 3 whitetails beyond 100 yards in my lifetime, and the furthest was 200 yards.

Build the rifle to where you hunt.
547C4415-9CCC-4BB6-BB60-AEFFFBF0C740.jpeg
 
i have :
308 ruger american cut down to 16"
223 ruger american 16" barrel
308 Remington 700 cut down to 16"
6XC deviance cut down to 16"

they have all killed deer, most even just with match bullets.
Except for the 223 i wouldnt hessitate a moment to shoot a deer at 300yards..

i like shorties soooo much, right now im starting a Remington 700 stricktly for hunting, it will have a 10 or 11inch barrel ( yes SBR )
caliber will be 6xc or 6 creedmoor and the plan is to shoot it inside of 200 yards

all rifles are suppressed, and even a 16" barrel with suppressor can get long...
 
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My main hunting rifles are a 20" 6.5 CM and an 18.5" .30-06, both chopped and threaded for suppressed use.

IMG_20181031_061751128.jpg


If the 6.5 were a few inches shorter, it certainly wouldn't have cost me any animals. I have a self imposed 400yd limit though, and the furthest I have taken animals was at 320 yds with last year's cow, and 375 yds with this year's cow:

IMG_20181111_144515197.jpg


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I'm often hunting pretty open areas, but every other animal I've shot has been at less than 300 yds. At those ranges, maximizing muzzle velocity and even BC isn't terribly critical.

I would suggest being picky about what 6.5mm bullets you use on elk though. I know people that have killed elk with 6.5mm Berger's, ELDxs, etc. I'd use those on deer and antelope, but personally I want something of heavier construction for larger game. I've used the 127gr LRX and 140gr Accubonds on the two elk I've taken with my 6.5. The Accubond is probably my favorite all around hunting bullet, lots of damage and good penetration with high SD versions. The higher SDs regular 6.5mm bullets boast tend to help with penetration, I haven't caught any 6.5mm bullets, but I did catch two 180gr .308 Accubonds last year (to be fair, after they went through lots of meat and bone).

I'd probably go with an 18" barrel personally, but I doubt going 16" instead would cost you anything you'd really miss. Bare muzzle, 16", 18" and 20" are all going to be really loud in full power rifle cartridges, I don't worry much about the difference, but suppressors are kosher everywhere I'm going to hunt.
 
16" 6.5 CM with a direct thread can attached (30P1) is perfect for my needs. I greatly prefer the maneuverability over the MV loss. Planning on taking on an elk hunt some day, but for now use it to kill lots of pigs and a few deer/varmints. Wasn't horrible the one time I shot it without a can on it, but I try to avoid that. Not as loud as an unsuppressed 5.56 MCX Virtus pistol....
 
Direct threads.
I have only ever shot prairie dogs "at distance" (450 yards). The furthest deer I've ever shot was at 75 yards, but elk hunting is on the calendar for next fall. I know this may be blasphemy, but I really can't see myself shooting at large game more than 300 yards away. Maybe I'll feel differently in the future, but that is my theoretical limit for now that I have pulled out of my a$$.
Yep, that's blasphemy
 
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I dropped my barrel off for threading yesterday with instructions to cut and crown it at 16.5" and thread appropriately. Thank you again for all of the great input and discussion on this thread.

I have the same rifle. Had it cut to 18” and threaded. I’ve only ever shot it supppressed.
the Hornady Precision Hunter 143 ELDX load chrono’d at avg velocity of 2450 with a Magnetospeed V2.
 
I find 18-20”s is my sweet spot on barrels lengths for suppressed hunting. Have some longer, mostly match or varmint type rigs...
18-20”s have been:
6 CM
22 CM
7/08
223
308
6.5 CM
260
7 WSM
6.5 PRC
6.5 SAUM