You have a 56-degree wedge and you know you hit it "about 90 yards." On the course you have 87 yards, so you pull it and hit it 94. Or 81. Or a partial swing you're not sure about comes up twelve feet short and you make bogey from inside 100 yards.
The gap between how far you think you hit each wedge and how far you actually carry it is costing strokes every round. A gapping session closes that gap with real numbers you trust.
What you're mapping
Every club you use from 100 yards and in, at full swing and at two or three partial swing lengths. For most players that means pitching wedge, gap wedge, sand wedge, and lob wedge if you carry one, at full, three-quarter, and half swing. That's twelve to sixteen data points. An afternoon's work that pays back every round.
You want carry distance, not total. Carry is what you control. Roll varies based on firmness, slope, and pin location. Map the carry and let the course tell you about roll.
How to run the session
Warm up until you feel like yourself. Then start with your most lofted wedge at full swing. Hit five balls to a specific target you can see clearly. Throw out any flyer or obvious mishit. Average the rest. Write it down.
Move to the next club. Keep going through all clubs and all swing lengths, resting between sets so your speed stays consistent. Don't do this session when you're tired or after a long range session. Tired swings produce numbers that are low and wrong.
Map your partial swings
This is the part most golfers skip, and it's where gapping work pays off most directly on the course. Full shots from wedge range are relatively rare. Partial shots are everywhere.
A simple standard: full swing, hands to shoulder height on the backswing, hands to hip height. Three different swing lengths, three different distances, same club. You now know what each of those looks like in the air. This is what gets you from 73 yards without guessing.
The gaps you'll probably find
Most players have a hole somewhere between their full pitching wedge and their 9-iron, or between their gap wedge and their sand wedge at full swing. These holes are where you need a deliberate partial swing with one club that you practice until you trust it.
Once you've identified a gap, build a drill around the specific distance: ten balls at that yardage from 50 feet behind the flag line, score proximity, same swing every time. You're not just mapping. You're building the skill.
Using the map on the course
You have 93 yards to the flag. Your map says full sand wedge is 95, three-quarter gap wedge is 88. You pick the three-quarter gap wedge and commit to it. That's a decision based on data, not a guess.
Over time, real-world carries may drift slightly from range numbers based on elevation, temperature, and altitude. Update one window at a time when something feels off in play, rather than re-doing the whole session.
Offcourse stores your wedge distances and tracks your proximity to the hole from scoring range so you can see the gapping session paying off in your scoring stats over time.