Welcome to the Configurator at riflespeed.com, an online calculator that makes it quick and easy to determine which model of RIFLESPEED Gas Control is right for your AR15- or AR10-style firearm. RIFLESPEED Gas Controls are currently available for barrels with a either 0.625" or 0.750" diameter gas journal. Gas Controls in either diameter are available in four lengths. The lengths are indicated by the last two digits of the model number. Choose an RS62 model for a .625" diameter journal or an RS75 model for a .750" diameter journal. Simply enter your firearm's details into the Configurator below. Based on your inputs, Gas Control models that DO fit your firearm will be highlighted in GREEN. Models that DO NOT fit your firearm will be highlighted in RED. If more than one model fits your carbine, we recommend selecting the shortest model in most cases.
An ideal fit places the Control Knob so that it protrudes between 0.5 inches and 2.0 inches beyond the front of your handguard. A minimum of 0.4 inches is required for sufficient access. The Configurator is set to allow a minimum of 0.4 inches of exposed Control Knob. If you have a muzzle device that extends behind the thread shoulder you’ll need to subtract the rearward extension length from your barrel length measurement.
Measure the distance from the front of your upper receiver to the end of your barrel, including the muzzle threads. Enter or select this number in the Barrel Length field in the Configurator.
To determine your Gas System, measure the distance from the front of your upper receiver to the back of your gas block or the shoulder against which your gas block will seat. This distance is represented by the green line in this picture:
The most common gas system lengths are:
- Pistol - 4.3 inches from receiver to gas block journal
- Carbine - 7.3 inches from receiver to gas block journal
- Midlength - 9.3 inches from receiver to gas block journal (shown in the image below)
- Rifle - 12.6 inches from receiver to gas block journal
Enter or select the appropriate Gas System Length in the Configurator. Also make note of this information to reference when purchasing the corresponding straight gas tube for your configuration.
Next, measure your handguard and enter or select that size in the Handguard Length box in the Configurator. You will now see color-coded fitment results. If all models are shown in red then your handguard is likely a bit too long. That's the most common issue that prevents successful fitment. Try reducing the measurement in the Handguard Length box until you get a green instead of a red on one of the four Gas Control models.
If your exact configuration is not listed in the configurator you can use the color-coded image below to determine which model of Gas Control fits your needs. The color-coded image overlays each Riflespeed Gas Control model over four upper assemblies with different gas systems. From Top to bottom these represent a Pistol-length gas system, Carbine-length gas system, Mid-length gas system, and Rifle-length gas system.
Using the color-coded image below and the example of an 11.5-inch barrel with a Carbine-length (7.3-inch) gas system, 0.750" journal diameter, and a 9.5-inch handguard we can determine that the correct model of Riflespeed Gas Control is the RS7533 represented in green.
There is a helpful article with information and pictures that cover in more detail how to get the right measurements of your firearm's components here:
Here's a quick video showing the process of determining your configuration:
Click this link once you've determined the correct size Gas Control for your carbine.
If there are no models that fit your configuration feel free to email [email protected] and we'll work to determine the best path forward. In some configurations there simply is no compatible Gas Control due to a lack of clearance in front of the handguard. If your configuration is not compatible we can suggest several options.