Let’s Take A First Look At Airgun Barrel Twist Rates

This is the second post in our series about airgun barrel twist rates.


Airgun Barrel Twist Rate Assumptions

First I’m going to start this discussion on airgun barrel twist rates with some guesses and assumptions. Are they right or wrong? Somebody will certainly tell me, or we will find out…

Assumption 1. Before we start looking to find data in confirmation, my guess is that one of the most common twist rates for .22 caliber airgun barrels is 1:16. We’ll find out if this is true in future.

Assumption 2. It seems that the “traditional” and most common twist rate for .22 Long Rifle firearms barrels is 1:16.

As .22 LR firearms were in existence well before mass-production airguns, my GUESS is that 1:16 became a common twist rate for .22 caliber airguns because the machinery and tooling already existed and worked well for .22 LR. After all, why mess with success?

 

So far as I am aware, the earliest Crosman airguns were in .22 caliber. There’s some evidence for my assumption!


Manufacturers Specifications For Airgun Barrel Twist Rates

OK, so what do manufacturers say about the twist rates in their airgun barrels?

First, let’s start with one of the most prestigious airgun barrel manufacturers in existence. Lothar Walther.

Lothar Walther publishes detailed specifications for its range of “non custom” airgun barrel blanks. Here’s the range:

.177 Caliber Lothar Walther Airgun Barrel Twist Rates

CaliberTwist RateGroovesNotes
.1771:1612
.1771:17.76Polygonal Rifling
.1771:2012
.1771:366

.20 Caliber Lothar Walter Airgun Barrel Twist Rates

CaliberTwist RateGroovesNotes
.201:17.712

.22 Caliber Lothar Walter Airgun Barrel Twist Rates

CaliberTwist RateGroovesNotes
.221:1612
.221:17.712
.221:2012
.221:3012

.25 Caliber Lothar Walter Airgun Barrel Twist Rates

CaliberTwist RateGroovesNotes
.251:17.76Polygonal Rifling
.251:17.710
.251:3010

.30 Caliber Lothar Walter Airgun Barrel Twist Rates

CaliberTwist RateGroovesNotes
.301:166

Now let’s look at the barrel twist rate specifications given by some of the airgun manufacturers at the 2024 IWA OutdoorClassics show.

ManufacturerCalibersTwist RateGrooves
AirMaks.177, .22, .251:17.7N/a
Epic (option 1).177, .22, .251:17.712
Epic (option 2).177, .22, .251:17.76
KalibrGun.177, .22, .25. 301:17.712
KalibrGun (Cricket II Smooth).301:29.912
Macavity.1771:17.712
Macavity.221:21.812
Macavity.251:23.410
Macavity.301:22.26
RTI.1771:17.7N/a
RTI.221:16N/a
RTI.251:20N/a
RTI.301:16N/a

Below we have the twist rates published by Karma Airguns. This applies to the Red Panda and other models.

CaliberTwist Rate - Pellet BarrelTwist Rate - Slug BarrelGrooves
.221:17.71:16N/a
.251:17.71:16N/a
.301:241:16N/a
.361:281:22N/a

Interesting, huh?

In the next part of this investigation, we’ll move-on to make some actual measurements of airgun barrel twist rates for air rifles available to the HAM Team. That will add some “real life” test data to the mix.