How to Install Choke Tube

Despite the connotations and assumptions brought about by the likes of video games and movies, the humble shotgun is a highly versatile firearm that any hunter or sports shooter worth their salt should include in their arsenal.

Shotguns owe their versatility to chokes, tiny devices that can be attached to the front of the barrel to change the pattern of the shot when the gun is fired. Chokes can also increase the accuracy of the shot and the range of the shotgun itself. 

The variety of choke tubes allows hunters to specialize their shotgun according to the hunt. For instance, if a hunter is hunting turkey, the optimal range and shot pattern will need to be changed from the specifications they would use if they were hunting quail or dove.

Of course, there are several variations of choke tubes and each one is better suited to hunting one type of game over another. Installing these choke tubes will require a fair bit of elbow grease, but their versatility will be well worth the effort. So below, we are going to look at how to install choke tube units to on your shotgun. Without further ado, let’s get right into it!

What are the different kinds of choke tubes?

As mentioned, choke tubes come in various forms and each one excels at specific ranges where the others do not. So what are the different types of choke tubes? Take a look below.

Cylinder Choke

The cylinder choke is, perhaps, the most basic type of choke tube and, as such, is also the most commonly used. The cylinder choke is not restricted, which means that the flight patterns of shots are widespread – consequently, their viable range is much shorter. Still, they can completely devastate targets within 15 to 20 yards.

Improved Cylinder Choke

The improved cylinder choke is still most effective at close-range but it tightens the spread of each shot by around 10%. This slight decrease in spread could mean the difference between a miss and a hit. Because the choke is less constricted, it is effective within 20 to 30 yards.

Modified Choke

The go-to choice for experienced hunters, the modified choke is more constricted than any of the previous chokes, allowing each shot to travel farther before spreading. Naturally, a keen eye is required for this type of choke to be effective at shorter ranges, and it is most effective at mid-ranges within 30 to 40 yards.

Full Choke

Finally, following the modified choke is the full choke, which is almost wholly constricted, allowing each shot to travel much farther before spreading out. Generally, full chokes are never used at short ranges because of this. However, they are incredibly effective at ranges between 40 to 50 yards and beyond and are favored by sharp-eyed hunters who prefer to keep as much distance as possible.

In addition to these four basic types of choke tubes, several other modified chokes are used under specific circumstances, though the average hunter may never need to use them.

How do you install a choke tube?

Choke tube installation is usually completed by professional gunsmiths using a lathe. However, for this guide, we will show you how you can install a choke tube on your shotgun with an essential toolkit and without a lathe so that you can do it at home or in your workshop before you head out hunting.

Step One

First, make sure that your shotgun is unloaded, then remove the barrel and thoroughly clean the bore. Your first order of business will be to determine the bore diameter of your shotgun. Measure the length between the barrel’s forcing cone and the point where the choke begins. If your shotgun does not have a choke, simply measure the length between the forcing cone and the very end of the barrel.

Different gauges yield different standardized measurements. For example, a 12 gauge will have a bore diameter of 0.729 inches, while a 20 gauge will have a bore diameter of 0.617 inches. Of course, these measurements are standardized and some variations may exist between manufacturers. 

One will deduct the measurement of the choke you choose to apply from the bore diameter. This final measurement will determine whether or not one can safely fit your shotgun with a choke.

As a general rule, choke tubes cannot be installed into a barrel with an internal diameter more than: 0.781 inches for 10 gauge; 0.736 inches for 12 gauge; 0.668 inches for 16-gauge; 0.626 inches for 20 gauge; 0.560 inches for 28 gauge; and 0.416 inches for the .410 shotgun.

Step Two

Next, you will need to use your barrel seating spacer and your reamer. Begin by sliding the spacer over the reamer until it stops at the reamer’s most prominent area. 

Now, you will need to see whether or not your barrel has been chrome-lined. You will need to remove the chrome with some good old sanding paper if it is. Wrap some 220-240 grit emery cloth over a flat piece of board, then sand off the chrome.

Step Three

You will now need to remove any existing choke that the shotgun may be fitted with. To accomplish this, use one of the five steel pilots that your gun should have shipped with. You will need to choose one that can fit snugly into the bore while still permitting some wiggle room. 

Insert the pilot from the chamber end of the barrel, then maneuver it gently down the bore. It should come to a stop once it reaches the choke. 

Step Four

You will now need to do some cutting. To start, lock the barrel in a vise and apply some oil to the reamer and the inside of the bore. 

Now, insert the reamer into the bore while turning it clockwise 1/8th of an inch. Remove it, then clean out and re-lubricate the barrel, then make another 1/8 inch cut, clockwise. Continue this process until the barrel is rubbing against the seating spacer. 

Next, thread the barrel by hand after removing the spacer and installing the tap on the pilot. Apply some lube to the tap and slowly insert it into the bore. It should continue for about 17 full turns before it bottoms out. Once it does, carefully remove it and clean the bore.

Finally, you will also need to cut the choke seat. Do this by inserting the tooling assembly back into the bore. Lubricate the reamer and turn it clockwise. It should end up facing the end of the barrel. Finally, remove the reamer by turning it clockwise back out and cleaning out any chips.

Step Five

Now you can remove the barrel from the vise. Clean it thoroughly with a high-quality solvent, then apply some lubricant to an improved choke cylinder and install it. If you have completed everything properly up until this point, it should fit in smoothly and be flush with the muzzle.

Final Thoughts

And there you have it. Knowing how to install a choke tube is an important step in shotgun ownership. With this guide, you should be able to attach any improved choke tube to your shotgun of choice without the use of a lathe.

Still, if you have any doubts about your proficiency, it is always best to consult a professional gunsmith and let them complete the installation.