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NRA Probationary Course. Unit 8 The Rifle Sights. Compiled by Dave Burton. NRA Probationary Course. Unit 8 Introduces: Minutes of Angle Vernier Scales Elevation & Wind Settings Different types of sighting system. Elevation And Distance. When the rifle is close to the target
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NRA Probationary Course Unit 8 The Rifle Sights Compiled by Dave Burton
NRAProbationary Course Unit 8 Introduces: Minutes of Angle Vernier Scales Elevation & Wind Settings Different types of sighting system
Elevation And Distance When the rifle is close to the target the bullet hits the centre providing the sights are correctly set to the bore
Elevation And Distance But:- further away, the bullet drops due to gravity and air resistance
Elevation And Distance To hit the target the front of the barrel must be raised The longer the range, the more the barrel must be raised
x Firer Target Target ELEVATION • The further the distance from firer to target, the greater the angle ‘x’ has to be. trajectory • ‘x’ is the angle measured on the sight.
ELEVATION • Only a small change of angle is needed at the rifle end to make a big difference at the target end • The angle is measured in MINUTES of angle - (one minute is 1/60 of a degree) • At 100 yards, changing the sight by 1 minute, changes the fall of shot on the target by 1 inch
Minutes Of Angle The adjustment of the REARSIGHT that will cause the POINT OF IMPACT to move 1 Inch per 100 yards A minute of angle is:
ELEVATION • Therefore: Distance1 minute at the target is: 100yd 1” 200 yd 2” 300 yd 3” etc.
3 inches 2 inches 1 inch 100 yds 300 yds 200 yds ELEVATION 1 Minute
CHANGE RISE BETWEEN RANGES (yards) (minutes) 100 - 200 2.0 200 - 300 2.5 300 - 400 3.0 400 - 500 3.5 500 - 600 4.0 Approx elevation To Allow For Bullet Drop Over Set Distances
DISTANCE (yds) RISE (mins) 200 – 300 2.5 300 – 500 6.5 500 – 600 4.0 600 – 900 16.0 900 – 1000 7.0 Elevation This gives us the standard rises between ranges:
Elevation Vernier Settings 40 40 40 20 20 20 5 5 5 0 0 0 0 0 0 0 1 4
The Elevation Vernier Set at 6 minutes of elevation
The Elevation Vernier Set at 9 minutes of elevation
The Elevation Vernier Set at 13 minutes of elevation
The Elevation Vernier Set at 31 minutes of elevation
Target Target Still Air Still Air F P F P The Effects Of Wind On The Bullet
Light 2 mph Gentle 4 mph Moderate 8 mph Fresh 12 mph Strong 16 mph Very Strong 20 mph Range Flags/Wind Speeds
20 20 20 20 20 20 0 0 0 5 0 5 0 5 5 5 0 5 The Wind Scale 0 2 LEFT 3 RIGHT
The Wind Scale Set at 8 min left
Sight Systems Different target shooting disciplines may involve different types of sights eg. • Telescopic sights (F and Match class) • Leaf sights (Older military rifles) • Buckhorn sights (Gallery rifles)
“Service” Rifle Sights Note the different method of sight adjustment
Telescopic Sights Telescopic sight adjustment may be in the opposite direction to that of target sights
Leupold Sight Telescopic sight adjustment may be in the opposite direction to that of target sights
NRA Probationary Course Compiled by Dave Burton