Choke Tubes

Posted On: 03-24-2022

The variety of choke tubes on the market is huge.  With exception of those guns that have fixed chokes every other gun has options.  The purpose of this coaches newsletter though is not to explore those brands, but to better understand what standards exist for choke tubes.  The question many might ask is, “Are all choke tubes alike?”  Of course the answer is not even close.  Here are the standards we typically see:

Choke                          Constriction                Diameter

Cylinder                      .000                             .730

Improved Cylinder     .010                             .720

Skeet                           .005                             .725

Modified                     .020                             .710

Full                              .035                             .695

So you should begin to see a pattern here in that each choke starting with Cylinder Bore constricts the barrel by about .005”.  Those middle chokes of light modified, improved modified, and light full all separate themselves by .005” within the normal list of chokes. 

Now across brands, the above specifications may and do vary.  I wrote and article for Guns America in early November of 2021 specifically discussing the variations in choke tubes.  Here is a link to that article.  Without repeating the article I ask that you read the article, and notice how I show the variability in choke tubes.  Honestly, the only way to know exactly what you have, is measure it with a micrometer.  I argue that it is possible tubes vary by so much that one could purchase something like a light modified choke (.715) but when they measure the tube it is really .720 or .710 or in effect not a light modified but rather an improved cylinder or modified choke.  Here is a link for coaches to purchase a digital micrometer to make sure your kids are shooting what they think they are shooting. These are around $25.  

When measuring your choke, use a micrometer to know for sure what you are shooting.  Not a bad time to take one to the range and have all your youth shooters take the measurement so they really know what they have.  I also recommend you measure the tube at 90 degree angles across the diameter.  I say that because it is very possible to shoot the pattern board and see a point of impact (POI) high and then rotate the tube 180 degrees and see a POI that is low.  Obviously until you measure and shoot the pattern board you will never know.  Aside from ever doing either keep your tube tight.  Let me know if you have any questions and from MYSSA was wish you the best this spring and summer. 

David R. Vaught

Executive Director