Choke markings tell you how much the muzzle constricts the shot pattern. On imports, auction photos, and older fixed-choke guns, those codes are often the only way to know what you are buying — before you bid or file paperwork with MyGunImport.com.
Two of the most common systems look nothing alike: Beretta (and many Italian / European makers) stamp stars on the barrel near the muzzle, while Browning usually cuts notches into the rim of the choke tube. Confusing them is easy if you only count marks.
Beretta vs Browning at a glance
Where to look
Beretta. Fixed chokes: stamped stars on the barrel near the muzzle (often the underside). Screw-in Mobilchoke / Optima / Optima-HP tubes: letters or notches on the tube.
Browning. Almost always on the choke tube itself (Invector, Invector-Plus, or Invector-DS). Older fixed-choke Brownings may use letter stamps on the barrel.
Coding logic
Beretta. Stars work opposite of Browning notches: more stars = more open. One star is Full; five stars is Cylinder.
Browning. Rim notches: fewer notches = tighter. One notch is Full; five notches is Skeet; Cylinder often has no notches.
Do not mix tubes
Beretta. Mobilchoke, Optima, Optima-HP, and Steelium / Optima Bore HP geometries are not interchangeable across families.
Browning. Standard Invector, Invector-Plus, and Invector-DS are different thread/length systems — never mix them.
| Topic | Beretta | Browning |
|---|---|---|
| Where to look | Fixed chokes: stamped stars on the barrel near the muzzle (often the underside). Screw-in Mobilchoke / Optima / Optima-HP tubes: letters or notches on the tube. | Almost always on the choke tube itself (Invector, Invector-Plus, or Invector-DS). Older fixed-choke Brownings may use letter stamps on the barrel. |
| Coding logic | Stars work opposite of Browning notches: more stars = more open. One star is Full; five stars is Cylinder. | Rim notches: fewer notches = tighter. One notch is Full; five notches is Skeet; Cylinder often has no notches. |
| Do not mix tubes | Mobilchoke, Optima, Optima-HP, and Steelium / Optima Bore HP geometries are not interchangeable across families. | Standard Invector, Invector-Plus, and Invector-DS are different thread/length systems — never mix them. |
Beretta / Italian stars
More stars = more open
On many Beretta and other Italian / CIP fixed-choke barrels, choke is shown as a row of stars (asterisks) on the barrel wall near the muzzle — often on the side or underside a short distance behind the crown. Count them carefully: five stars is Cylinder (wide open); a single star is Full (tightest). That is the reverse of Browning’s notch logic.
| Marking | Constriction | Notes |
|---|---|---|
| ***** | Cylinder (C / CL) | No constriction — most open |
| **** | Improved Cylinder (IC) | Often marked ☆☆☆☆ |
| *** | Modified (M) | European “1/2” choke |
| ** | Improved Modified (IM) | European “3/4” choke |
| * | Full (F) | Tightest common fixed choke |
Screw-in Beretta systems (Mobilchoke, Optima, Optima-HP) often switch to letter stamps or rim notches on the tube instead of barrel stars. Tube families are not interchangeable.
Browning Invector notches
Fewer notches = tighter
Browning (and Miroku-built) guns with Invector, Invector-Plus, or Invector-DS tubes are usually identified by counting notches on the muzzle end of the tube — often while it is still installed. One notch is Full; more notches open the pattern toward Skeet and Cylinder. Always read the side stamp too: lead and steel ratings can differ on the same tube.
| Marking | Constriction | Notes |
|---|---|---|
| I (1 notch) | Full | — |
| II (2 notches) | Improved Modified | — |
| III (3 notches) | Modified | — |
| IIII (4 notches) | Improved Cylinder | — |
| IIIII (5 notches) | Skeet | — |
| No notches / hex | Cylinder | Some Cylinder tubes use a hex wrench flat instead of notches |
Confirm which Invector family the barrel is threaded for before ordering tubes. Standard Invector, Invector-Plus, and Invector-DS are not compatible.
Letter codes
Abbreviations on barrels and tubes
Many makers — including some Browning fixed-choke barrels and aftermarket tubes — stamp plain abbreviations on the side wall of the tube or on the barrel near the muzzle. Over-unders may show two codes (one per barrel).
| Marking | Constriction | Notes |
|---|---|---|
| C / CYL / CL | Cylinder | — |
| S / SK | Skeet | — |
| IC | Improved Cylinder | — |
| LM / 1/4 | Light Modified | — |
| M / MOD | Modified | — |
| IM | Improved Modified | — |
| F / FULL | Full | — |
| XF / XFULL | Extra Full | — |
