Threaded barrel question

Pahoo · March 8, 2016, 09:02 PM

Lately, I am seeing more "threaded barrels", on the market. To be more specific, these barrels are threaded at the muzzle end and covered by a cap or protector. My question is, are there any concerns/considerations physically? Regardless of the nut, the barrel is thinner and possibly weaker at the muzzle. I don't see the protector affording much strength and mostly there to protect the threads. I thank you for your time and replies. .....

Be Safe !!!

Roughedge · March 9, 2016, 04:20 PM

There's still enough meat on the barrel to hold up. The bigger the bullet the bigger the threads. most are 1/2x28 or 5/8x24. With suppressors being so popular they will be threading everything soon.

tobnpr · March 9, 2016, 05:43 PM

When threading, we consider the groove diameter of the barrel, and the minor diameter of the threads to determine the actual thickness of the barrel.

This is a frequent topic of discussion among those of us that do this, with no particular consensus or "rule of thumb" as to what minimum barrel wall thickness should be.

There was a post here recently somewhere about a rifle factory threaded 1/2" for .30 caliber. Major manufacturer, I'm sure they've done all the necessary calcs to know it's safe- but that's smaller than I'd ever go (9/16" for me).

There are many gunsmiths that feel even 9/16" is too small for .30 cal- but consider that the AK-47 is threaded 14 mm (roughly the same as 9/16") and the FAL is also threaded 9/16"...and I've not heard of barrels/muzzle devices failing on the millions of these in service.

When done by the manufacturer or competent machinist/gunsmith, no reason for concern.

ballardw · March 10, 2016, 02:32 AM

Swedish Model 96 Mausers had threaded muzzles for attaching a "blank firing" device that was basically a small cage to shred the wooden bullets used in their blanks.

I doubt that would have been done and used for as many years as these rifles were around if there had been an issue. The pressures involved with the live cartridges and the way soldiers tend to treat weapons would have revealed any inherit weaknesses in the threaded muzzle a long time ago.

Dixie Gunsmithing · March 12, 2016, 05:42 AM

I do not think the muzzle being threaded will hurt it any. The pressure at the muzzle is much lower than the chamber pressure, when the bullet reaches that point, and then, it suddenly drops to zero. The time that pressure is acting on the muzzle is down to nanoseconds, I would think.

March 8, 2016, 09:02 PM	#1
Pahoo Senior Member Join Date: February 16, 2006 Location: IOWA Posts: 8,783	Threaded barrel question Lately, I am seeing more "threaded barrels", on the market. To be more specific, these barrels are threaded at the muzzle end and covered by a cap or protector. My question is, are there any concerns/considerations physically? Regardless of the nut, the barrel is thinner and possibly weaker at the muzzle. I don't see the protector affording much strength and mostly there to protect the threads. I thank you for your time and replies. ..... Be Safe !!! __________________ 'Fundamental truths' are easy to recognize because they are verified daily through simple observation and thus, require no testing.

March 9, 2016, 04:20 PM	#2
Roughedge Senior Member Join Date: January 24, 2011 Location: Monroe,NC Posts: 669	There's still enough meat on the barrel to hold up. The bigger the bullet the bigger the threads. most are 1/2x28 or 5/8x24. With suppressors being so popular they will be threading everything soon. __________________ The man that die's with the most stuff win's!

March 9, 2016, 05:43 PM	#3
tobnpr Senior Member Join Date: August 1, 2010 Location: Tampa Bay Posts: 4,556	When threading, we consider the groove diameter of the barrel, and the minor diameter of the threads to determine the actual thickness of the barrel. This is a frequent topic of discussion among those of us that do this, with no particular consensus or "rule of thumb" as to what minimum barrel wall thickness should be. There was a post here recently somewhere about a rifle factory threaded 1/2" for .30 caliber. Major manufacturer, I'm sure they've done all the necessary calcs to know it's safe- but that's smaller than I'd ever go (9/16" for me). There are many gunsmiths that feel even 9/16" is too small for .30 cal- but consider that the AK-47 is threaded 14 mm (roughly the same as 9/16") and the FAL is also threaded 9/16"...and I've not heard of barrels/muzzle devices failing on the millions of these in service. When done by the manufacturer or competent machinist/gunsmith, no reason for concern. __________________ Remington 700/Savage Rebarreling /Action Blueprinting 07 FFL /Mosin-Nagant Custom Shop/Bent Bolts Genuine Cerakote Applicator www.biggorillagunworks.com

March 10, 2016, 02:32 AM	#4
ballardw Senior Member Join Date: September 19, 2008 Posts: 1,411	Swedish Model 96 Mausers had threaded muzzles for attaching a "blank firing" device that was basically a small cage to shred the wooden bullets used in their blanks. I doubt that would have been done and used for as many years as these rifles were around if there had been an issue. The pressures involved with the live cartridges and the way soldiers tend to treat weapons would have revealed any inherit weaknesses in the threaded muzzle a long time ago. __________________ -+-+-+-+-+-+-+-+-+-+-+-+-+-+ All data is flawed, some just less so.

March 12, 2016, 05:42 AM	#5
Dixie Gunsmithing Moderator Emeritus Join Date: April 27, 2013 Location: Ohio Posts: 1,923	I do not think the muzzle being threaded will hurt it any. The pressure at the muzzle is much lower than the chamber pressure, when the bullet reaches that point, and then, it suddenly drops to zero. The time that pressure is acting on the muzzle is down to nanoseconds, I would think.