How to choose a choke tube for Hunting

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My dear hunter friends… are you looking for the proper choke tubes for your hunting activities? This article shall allow you to quickly and easily understand which choke tube (and which constriction size) is best suited to your type of hunting. We shall not consider the type of animal you are used to aiming at, because we know that some wild ones get hit from different distances (hunting at dawn, when the birds come out of the shelters where they spent the night to look for food; still-hunting, the hunters move stealthily, they often linger in order to catch the birds off guard while they are flying from one tree to another to find a food source; hunting at evening, when the birds come back to the shelter to spend the night; stalking, hunting while moving without hiding in a blind). For this reason we shall start from essentially examining the shooting distance, falling into three categories: short, medium and long shooting distance.

Short distance shooting (within 20 metres).

Given that in order to shoot within a 20 metres distance it is better to use a short-barreled firearm, we recommend for extremely close shots, as for example in case of woodcock-hunting in the weald, the Dispersant choke tube (D), or, alternatively, an SK2 or C constriction size (*****).

For such shooting category the elongated barrel is not necessary, hence we suggest you use Flush choke tubes (internal) or:

  • for an improved performance, Extended +20 mm choke tubes;
  • for an improved performance and recoil reduction, Ported +20 mm choke tubes.

In the event that your shotgun is equipped with two barrels, we recommend for the second one a C constriction size (*****) or, alternatively, an SK1 or IC (****) one, with the same type of choke tubes.

It is absolutely not recommended to use long-barreled shotguns for close distance shooting, for this reason, we also advise against the purchase of extensions or choke tubes lengthening the barrel, since they would not render your shot more effective.

Medium range shooting (20/35 metres).

If you are rather used to shooting distances between 20 and 35 metres, the recommended constriction size is definitely the M one (***), the so-called " all-round hunting ". Alternatively, we suggest using an IC constriction size (****).

If the barrel of your shotgun is short, namely between 60 and 70 centimetres, as a priority choice for medium distance shooting we recommend an In/Out +50 mm choke tube. The latter shall allow you to improve the shooting performance without inevitably purchasing a longer barrelled shotgun. Either way you can use Flush (internal), Extended +20 mm and Ported +20 mm choke tubes.

If you own a shotgun whose barrel is between 70 and 80 cm, you may opt for Flush (internal), Extended +20 mm or Ported +20 mm choke tubes.

Whereas your shotgun is provided with two barrels, we suggest an M (***) or, as an alternative an IM (**) constriction size on the second barrel, with the same aforementioned choke tube type (depending on the length of the barrels).

Long range shooting (35/50 metres).

As for long distance shooting, which sometimes are unattainable, we can solely choose an F (*) tight constriction size or even an extremely tight one such as XF, XXF (Extra Full, Extra-Extra Full) otherwise, if shots are not so unachievable, we do confidently recommend an IM (**) constriction size.

If the barrel of your shotgun is short, the only possible choice is an In / Out +100 mm choke tube. If you want to use a Flush (internal), Extended +20 mm or Ported +20 mm choke tube, it is necessary to use an Extension +100 mm. The latter can equally be used with the choke tubes originally supplied with your shotgun.

If the shotgun barrel length is between 70 and 75 cm, an In / Out +50 mm choke tube is sufficient.

Whereas your shotgun is more than 75 cm long, it is advisable to rather opt for Flush (internal), Extended +20 mm or Ported +20 mm choke tubes.

In case your shotgun is equipped with two barrels, we recommend you use an IM (**) or F (*) constriction size on the first barrel while an F (*), XF or XXF on the second one. As for the choke tube type refer to the above (depending on the length of the barrels).

Warning: the extensions, depending on the thickness of the rib, can seldom be used on 2-barreled shotguns since the outer diameter, which is larger, prevents their simultaneous mounting.

In addition remember that, considering the fast burning rate powders currently marketed for cartridges loading, you do not need to extend the barrel of your shotgun over 80 cm

For any hunting type, the suited choke tubes.

To further simplify the explanation and guide you correctly for the best choice, we have drawn the table below showing the shooting distances and the relevant choke patterns, so as to specifically identify the two, three models best suited to your needs.

Short barrel
60-70 cm
Medium barrel
70-75 cm
ong barrel
over 75 cm
Constriction size
Short distance shootingSemi-automatic Flush, Extended, Ported Flush, Extended, Ported not recommended D, SK2, C
First barrel Flush, Extended, Ported Flush, Extended, Ported not recommended D, SK2, C
Second barrel Flush, Extended, Ported Flush, Extended, Ported not recommended C, SK1, IC
Medium distance shootingSemi-automatic In/Out +50 Flush, Extended, Ported Flush, Extended, Ported IC, M
First barrel In/Out +50 Flush, Extended, Ported Flush, Extended, Ported IC, M
Second barrel In/Out +50 Flush, Extended, Ported Flush, Extended, Ported M, IM
Long distance shootingSemi-automatic In/Out +100, Extension con Flush, Extended, Ported In/Out +50 Flush, Extended, Ported F, XF, XXF
First barrel In/Out +50, In/Out +100 (#) In/Out +50 Flush, Extended, Ported IM, F
Second barrel In/Out +50, In/Out +100 (#) In/Out +50 Flush, Extended, Ported F, XF, XXF

# the convergence of the tubes has to be assessed

With the help of several hunters, friends of “Gemini”, we have drawn up a series of ad hoc articles concerning the wildfowl species most sought after by enthusiasts. From wildfowl like ducks and pheasants also encompassing hares: find out in the section dedicated to Hunting what are the best suited chokes for… it’s up to you!

What about hunting in wetlands?

Before concluding, let us spend a few words on this particular situation. If you are used to hunting in wet areas you certainly know that the legislation provides for the use of lead-free ammunition only. The latter are suitable to all of Gemini choke tubes bearing the words Steel Shot or the lily drawing (they are obviously usable also with lead ammunition).

Extended +20 mm, In/Out +50 and +100 mm choke tubes provided with such engraving are available from the largest constriction size up to the F (*), while Flush (Internal) and Ported +20 mm choke tubes, due to ballistic specific reasons, are featured with the largest constriction size exclusively up to the M (***) one . Whereas the choke tube DOES NOT bear the indication Steel Shoot (or the lily drawing) unleaded ammunition cannot be used, therefore the relevant mounting is impossible in wetlands.

Letters, stars and values.

To understand the correspondence among the different systems for indicating the constriction sizes value (letters, *, decimals) refer to the table below.

Flush (internal)
with 7 constriction sizes
Flush (internal)
with 14 constriction sizes
Ported and
In/Out +50
In/Out +100
XXFExtra Extra Full- - - 1,14 -
XFExtra Full- 1,20 1,10 1,02/1,20* 1,20
FFull* 1,00 1,00 0,89/1,00* 1,00
--- - 0,90 - -
--- - 0,80 - -
LFLight Full- - - 0,76 -
IMImproved Modified** 0,75 0,70 0,63/0,75* 0,75
--- - 0,60 - -
MModified*** 0,50 0,50 0,50 0,50
--- - 0,40 - -
LMLight Modified- - - 0,38 -
ICImproved Cylinder**** 0,25 0,30 0,25 0,25
--- - 0,20 - -
--- - 0,10 - -
SK1Skeet 1- - - 0,15/0,13* -
CCilinder***** 0,10 0,00 0,00/0,10* -
--- - -0,10 - -
SK2Skeet 2- -0,30 -0,30 -0,30 -

* the constriction size may vary depending on the model range, consult the catalogue for more details