Question 1

How do I get my barrel threaded?

Accepted Answer

Please visit our "Services" page and submit an order for muzzle threading. After placing an order you will receive an email containing shipping instructions.

Question 2

How are barrels threaded at Diamond C Precision?

Accepted Answer

How a barrel is indicated in the lathe is crucial to a quality thread job. There are many different methods of indicating barrels used by other gunsmiths such as using bushings, gauge pins, indicating rods, etc. These methods can all negatively affect your indicator reading because of stacked tolerances or improperly fitting bushings or gauge pins. Because of this, we indicate all of our barrels with special indicators that allow us to reach inside the bore and read directly off the lands and grooves of the barrel. This allows us to remove any variables other methods may have and indicate our barrels as close to zero runout as possible. Before threading, barrels are indicated to under .0002” TIR. For reference, that is approximately 1/10th the diameter of an average human hair (~.002”).

After indication, barrels are turned down to specified dimensions for the desired thread and single-point threaded to Class 3A specifications using high quality carbide tooling. We measure every single barrel with a thread pitch micrometer to ensure that our muzzle threads are properly sized and will be compatible with all muzzle devices.

Question 3

What thread size/pitch should I choose?

Accepted Answer

This is dependent on a number of factors. If you already have the muzzle device/suppressor you plan to use, check to see what thread spec it is compatible with. Typically, .22 and smaller caliber rifles are threaded 1/2"-28, and .243-.30 caliber rifles are threaded 5/8"-24; however, there are many exceptions. Please also reference our minimum barrel diameter table. If you need additional help, feel free to give us a call or send us an email.

Question 4

Is my barrel diameter large enough to thread?

Accepted Answer

The thread shoulder is an extremely important feature that your suppressor or muzzle device “squares” up against to provide concentricity with the bore. Because of this, when you are using a suppressor, you must allow at least .100” over the major diameter of the threads for the thread shoulder. This means that there are minimum muzzle diameters for threading as shown below.

1/2”-28:	.500”+.100”    =.600” Min. Barrel Diameter
9/16”-24:	.5625”+.100”  =.6625” Min. Barrel Diameter
5/8”-24:	.625”+.100”     =.725” Min. Barrel Diameter
3/4”-24:	.750”+.100”    =.850” Min. Barrel Diameter

If your barrel does not meet the minimum barrel dimensions above, there are other solutions as long as your barrel is at least .020” over the thread’s major diameter. One option is a threaded shoulder. We permanently install a threaded shoulder and machine to be perfectly concentric to the bore. This will allow your suppressor the required shoulder it needs to prevent concentricity issues.

If your barrel still does not meet the minimum diameter for your desired thread pattern, we can install a permanent thread adapter. This follows the same concept as the threaded shoulder, but will allow your barrel to be threaded 5/8”-24 or larger when your muzzle diameter is otherwise too small. There are many options on the market for thread adapters; however, if not machined properly, concentricity issues can arise due to excessive runout or tolerance stacking which can cause baffle strikes damaging your suppressor. Our permanently installed thread adapters are machined directly on your barrel after being indicated in a lathe. This means that the threads and added shoulder will be perfectly concentric to the bore. This process requires a minimum muzzle diameter of .520”.

Barrels that are contoured with a taper can also sometimes be shortened to a point where the muzzle diameter is large enough to provide the required shoulder.

Question 5

What is your lead time for Muzzle Threading?

Accepted Answer

Our current lead time is 5-10 days. This is subject to change.

Question 6

Do I need to disassemble my rifle for threading?

Accepted Answer

Most barrels longer than 18" can be threaded while still attached to the action; however, all other parts and accessories (Stock, scope rings/bases, trigger, magazines, etc.) must be removed prior to threading. Barrels that are shorter or that will be cut shorter than 18", must be removed from the action. Diamond C Precision can disassemble/reassemble your rifle for an additional fee. Please contact us for more details.

Question 7

What if a desired threading option is not available on your website?

Accepted Answer

Please contact us for any other services not listed on our site.

Question 8

Should I clean my barrel before I send it?

Accepted Answer

Yes. Our threading process requires us to indicate your barrel directly off its bore. A dirty barrel can cause inaccurate indicator readings. Extremely dirty barrels may be subject to additional charges.

Question 9

What should I include when I send my barrel for threading?

Accepted Answer

After placing an order, you will receive an order confirmation by email.   This will include your contact information, desired services, and return shipping address.   Print off the order confirmation page and enclose it in your shipment.   Failure to do so will result in a delay.

Question 10

How much is return shipping?

Accepted Answer

Return shipping is typically $10-30 depending on shipping weight/dimensions and the value for insurance.

FAQ