The F3 features two original Briley screw-in chokes in your choice of flush to muzzle as a standard. Unlimited steel proofing up to half a choke. Original Briley "spectrum" extended screw-in chokes as an option.

Choke/lead choke	Ristriction	Notches	Corresp. steel shot
Cylinder*	0,000 mm	none	Skeet
Skeet	0,125 mm	none	1/4 Choke (improved cylinder)
1/4 Choke (improved cylinder)	0,250 mm	I	1/2 Choke (modified)
1/4 - 1/2 Choke** (light modified)	0,380 mm	-	3/4 Choke (improved modified)
1/2 Choke (modified)	0,500 mm	II	1/1 Choke (full)
3/4 Choke (improved modified)	0,625 mm	III	no steel
3/4 - 1/1 Choke** (light full)	0,750 mm	-	no steel
1/1 Choke (full)	0,850 mm	IIII	no steel
5/4 Choke** (extra full)	1,050 mm	-	no steel

*   only available with chokes flush to muzzle     
** only available as elongated version (Spectrum choke)
     Titanium chokes optionally available
     ( approximately 50 % lighter, not for use of steel shot!)
     in extended version only

Changeable chokes for lead shot, German version	Changeable chokes for lead shot, English version	Marking on the muzzle
Cylinder	Cylinder (cy)	none
Skeet (sk)	Skeet (sk)	none
1/4	improved cylinder (ic)	1 notch
1/2	modified (m)	2 notches
3/4	improved modified (im)	3 notches
1/1 or full	full (f)	4 notches
5/4 or extra full	extra full (ef)	5 notches

Note:
Steel shot causes a significantly lower shot string than lead shot.

Effect of the changeable chokes when using
steel or lead shots: 

• Skeet (SK) with lead shot corresponds with 1/4 (IC) with steel shot.
• 1/4 (IC) with lead shot corresponds with 1/2 (M) with steel shot.
• 1/2 (M) with lead shot corresponds with 3/4 (IM) with steel shot.