I shot in a high power rifle match today and saw someone using an AR with a non-threaded barrel.  It appeared to be a 16" carbine length.  It sounded like a cannon going off and belched a fireball with every shot which was visible in broad daylight.  What made it look badass was the shooter had a cigar in his mouth while shooting.   The shooters next to him were well aware of the concussion from each shot.

Later after the match, I came up with two questions: 

1. Is there an advantage to a non-threaded barrel, other than the fact that you do not need to ruin a good barrel by pinning or welding a muzzle device to it to satisfy a stupid PRNJ law?

2.  Does a 20" or 24" non-threaded barrel allow the gases to burn more completely, thus eliminating the fireball and/or reducing the concussion? 

The advantages to a non-threaded barrel are that there's no muzzle device, you have more options as to how to crown the barrel, you can't screw up the barrel's accuracy during threading, and it's easy to inspect and clean your crown. 

I'm sure eventually a long enough barrel with quiet it and reduce muzzle flash, but 20" isn't it and neither is 24". 

 

 

Maybe it sounded loud because other shooters had longer barrels, but apples to apples with barrel length, the nude muzzle is the quietest usually.  Compared against a braked 16" barrel, I bet it would sound a lot quieter 

I have no muzzle devices on any of my ARs.  Yes a compensator or muzzle brake will allow you to recover faster between shots.  However, there are few people that shoot that good it's going to make a difference.

Thanks for the replies.  It did dawn on me that follow up shots could be slower without a muzzle device but I forgot to mention it in my original thread.  

I didn't realize the non-threaded barrels were as common as they are.  I did some searching online and they are not difficult to come by.

I think most people have a brake or compensator for looks.  They feel they have to have something on the muzzle because they can't have a flash surpressor.

I do see more muzzle flash from crowned barrels... and more overall noise, however brakes tend to add to the CONCUSSION... like, the chest thumpiness.  

Keep in mind a flash surpressor is designed to minimize the flash to the shooter so as not to affect night vision. There is plenty of muzzle flash to the sides and front of a rifle equipped with a flash surpressor.  You are never going to surpress the flash enough so it's not visible down range.

The original CAR-15 or XM177 in the 60s was a short barrel (12" IIRC) M16 with a standard flash surpressor. They found muzzle flash to be quite excessive and eventually adopted a flash surpressor that was over 4" long.  Kind of defeated the purpose of trying to make the rifle shorter.

The way to really surpress muzzle flash is with a longer barrel which allows for more complete burning of the powder.

Although not seen with flash surpressors shotguns with a 14" barrel have much more muzzle flash than an 18" barrel.  Use a 26" barrel and the flash is minimal.  If you can get in the right lighting conditions compare the muzzle flash of  a Shockwave or TAC14 to a 26" barrel.

 

The best way to reduce overall muzzle flash is to buy ammo designed to reduce the flash.

Ammo design has more to do with reduction of flash than any muzzle device.

Some sanctioned competitions/matches require that the rifle have no muzzle device so as to reduce discomfort to fellow shooters. 

I can tell you that if the guys next to me on the line with their F-Open 284 Shehane had a brake that I wouldn’t be able to shoot as they’re annoyingly loud un-braked. 

On 8/14/2018 at 10:10 PM, GRIZ said:

I think most people have a brake or compensator for looks.  They feel they have to have something on the muzzle because they can't have a flash surpressor.

Or to get to 16”

2 hours ago, Zeke said:

Or to get to 16”

True but there are 16"barrels out there too.

10 minutes ago, GRIZ said:

True but there are 16"barrels out there too.

Pax

What type ammo is designed to increase the flash?

5 minutes ago, SJG said:

What type ammo is designed to increase the flash?

Cheap stuff, Blaster ammo.  Doesn't burn as fast or completely...

12 hours ago, SJG said:

What type ammo is designed to increase the flash?

None. But slower burnign powders may not burn completely before the bullet exists, which increases flash. Some powders have a flash suppressant added, but that costs more, and not all powders have it. 

Muzzle flash and surpressing it are concerns if your fighting at night (think home defense).  You'll lose your night vision with the first round.  So will your opponent if he sees it.

All ammo gives some muzzle flash.  You generally get a large muzzle flash in handgun ammo from +P and +P+. You'll get one in a lot of standard velocity ammo too.  Smallest muzzle flash I've ever seen in 9mm is from WW 115gr Silvertip.  Just a small blue flame from a 3 1/2" barrel. That was before flash surpressants were in wide use.

Could be the powder he is using,  .... When I used H335 powder, it produced a 3 foot fireball out of the muzzle...  I switched over to W748 and have only a 6 inch flame....  I do not have a muzzle break or god forbid, a flash hider,  just a plain Jersey legal target crown.