One of the top questions we get is what does EF stand for on a choke. EF is usually written on the outside walls of the choke tube and it can be confusing if you haven’t seen it before.
EF stands for EXTRA FULL. It designates the choke tube constriction size and in this case EF is between a Full and Turkey choke with regards to tightness. It measures 0.040” in diameter.
Extra full chokes are used for turkey hunting and they help provide tight patterns at distances of over 40 yards. If you see “EF” written on a choke tube, you can be sure it’s tighter than a full choke.
Related – Looking for a NEW choke tube? Check out the top picks here.
What does EF stand for on a choke tube?
Choke tube letters designate what diameter a choke tube is and EF is included in these designations. EF stands for Extra Full and is the second tightest choke other than those marked as turkey chokes.
Some chokes can be labeled as ER and this means Extended Range. This designation is brand specific and isn’t related to the standard naming scheme. Extra full will be listed as EF, Xtra, or Extra.
What is the diameter of extra full chokes?
Extra full diameters differ based on shotgun brand and choke system. Below is a chart showing the diameter of extra full choke by brand.
EF Choke Tube Chart
| Type | Diameter (EF) |
|---|---|
| Beretta/Benelli Mobil | 0.681 |
| Beretta Optima Plus | 0.687 |
| Benelli Crio | 0.682 |
| Benelli Super Sport | 0.682 |
| Beretta Optima | 0.687 |
| Bettinsoli | 0.684 |
| Blaser | 0.687 |
| Browning Invector | 0.682 |
| Invector Plus | 0.695 |
| Remington | 0.682 |
| Winchester Imvector | 0.690 |
What are EF choke tubes used for?
EF choke tubes pattern tightly and hold the pellets together at longer ranges. They are ideal for precise shots over 40 yards. Because of this, they make perfect turkey and predator choke options.
Are EF choke tubes the tightest chokes?
EF choke tubes are the second tightest choke tube. Only 0.665 “turkey” chokes are tighter. EF chokes are tighter than full chokes. Regardless, the differences are small between the three.
Extra full chokes excel with lead shot, especially smaller shot in #4 though #8. They also can be used with TSS shot which delivers devastating downrange patterns on turkeys.
Summary
EF stands for extra full. It will be written on the side of the choke tube. Extra full chokes perform in between that of a full choke and turkey choke.
Extra full chokes are great for turkey hunting and are capable of delivering tight patterns at over 40 yards with lead, hevishot, and TSS.
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