Ballistic range compensation for projectile weapon aiming based on ammunition classification

15 Pages·2013·1.23 MB·English

US 20090199702A1
(19) United States
(12) Patent Application Publication (10) Pub. No.: US 2009/0199702 A1
Zaderey et al. (43) Pub. Date: Aug. 13, 2009
(54) BALLISTIC RANGE COMPENSATION FOR (60) Provisional application No. 60/518,377, ?led on Nov.
PROJECTILE WEAPON AIMING BASED ON 4, 2003.
AMMUNITION CLASSIFICATION
Publication Classi?cation
(75) Inventors: Serge Zaderey, Beaverton, OR
(US); Steven R. Timm, MilWaukie, (51) Int. Cl.
OR (US); Gary R. Williams, West F41G 1/00 (2006.01)
Linn, OR (US); Victoria J. Peters, F41G 1/38 (2006.01)
Vernonia, OR (US); Laura Peter,
Whites Creek, TN (US); Tim (52) U.S. Cl. ........................................ .. 89/41.17; 42/122
Lesser, Forest Grove, OR (US);
Tim L. O’Connor, Portland, OR (57) ABSTRACT
(Us)
A reticle of a projectile Weapon aiming system such as a
Correspondence Address: ri?escope includes a primary aiming mark adapted to be
sighted-in at a ?rst selected range and further includes a
STOEL RIVES LLP - PDX
plurality of secondary aiming marks spaced apart beloW the
900 SW FIFTH AVENUE, SUITE 2600
primary aiming mark. The secondary aiming marks are posi
PORTLAND, OR 97204-1268 (US)
tioned to compensate for ballistic drop at preselected incre
(73) Assignee: Leupold & Stevens, Inc., mental ranges beyond the ?rst selected range, for a selected
Beaverton, OR (US) group of ammunition having similar ballistic characteristics.
Angles subtended by adjacent aiming marks of the reticle can
(21) App1.No.: 12/163,333 be adjusted by changing the optical poWer of the ri?escope, to
thereby compensate for ballistic characteristics of different
(22) Filed: Jun. 27, 2008
ammunition. In some embodiments, the reticle includes a set
of Windage aiming marks spaced apart along at least one
Related U.S. Application Data
secondary horizontal axis intersecting a selected one of the
(62) Division of application No. 10/933,856, ?led on Sep. secondary aiming marks, to facilitate compensation for the
3, 2004. effect of crossWinds on the trajectory of the projectile.
Patent Application Publication Aug. 13, 2009 Sheet 1 0f 7 US 2009/0199702 A1
F|G|.110 50 34
K26
44
28 32 x
\ , 18 30 40 H-1
22 FIG. 2 26
Patent Application Publication Aug. 13, 2009 Sheet 2 0f 7 US 2009/0199702 A1
FIG. 4
40
62
62 A
52 94a
66 92a
94a 9J2a 720
W; \ i
84 8O
78
Patent Application Publication Aug. 13, 2009 Sheet 3 0f 7 US 2009/0199702 A1
FIG. 5
Patent Application Publication Aug. 13, 2009 Sheet 4 0f 7 US 2009/0199702 A1
FIG. 6
268a 286
288/2843 I 2845 \
286 268b 288
286
276
278/
Patent Application Publication Aug. 13, 2009 Sheet 5 0f 7 US 2009/0199702 A1
Patent Application Publication Aug. 13, 2009 Sheet 6 0f 7 US 2009/0199702 A1
FIG. 9
Patent Application Publication Aug. 13, 2009 Sheet 7 0f 7 US 2009/0199702 A1
US 2009/0199702 A1 Aug. 13, 2009
BALLISTIC RANGE COMPENSATION FOR in the ri?escope to compensate for bullet drop at different
PROJECTILE WEAPON AIMING BASED ON ranges. Exemplary ri?escopes are disclosed in US. Pat. Nos.
AMMUNITION CLASSIFICATION 3,190,003 of O’Brien; 1,190,121 of Critchett; 3,392,450 of
Herter et al.; 3,431,652 ofLeatherWood; 3,492,733 ofLeath
RELATED APPLICATIONS erWood; 6,032,374 ofSammut; and 6,591,537 ofSmith. Most
[0001] This application is a divisional application of US. of these patents propose ri?escopes providing a plurality of
patent application Ser. No. 10/933,856, ?led Sep. 3, 2004, range-related aiming marks accompanied With aiming mark
Which claims the bene?t of US. Provisional Patent Applica selection devices, the use of Which depends on relative height
tion No. 60/518,377, ?led Nov. 4, 2003, both of Which are of the image of a target of knoWn or estimable height com
incorporated herein by reference. This application is also pared to the height of a feature in the reticle.
related to US. design Pat. Nos. D506,520, D517,153, and [0006] Using modern laser range?nders and other ranging
D536,762 all titled “RETICLE FOR A GUNSIGHT OR techniques, it is noW possible to quickly determine a range to
OTHER PROJECTILE WEAPON AIMING DEVICE” and target more accurately than by using one of the range-?nding
?led Nov. 4, 2003. reticles described above.
[0007] US. Pat. No. 3,948,587 ofRubbert proposes a ri?e
TECHNICAL FIELD
scope With a reticle that includes vertically adjacent target
[0002] This application relates to projectile Weapon aiming spanning and aiming apertures dimensioned so that When a
systems such as ri?escopes, to reticle con?gurations for pro target of knoWn or estimable siZe is framed in one of the
jectile Weapon aiming systems, and to associated methods of apertures, the gun is thereby aimed for the correct range to the
compensating for ballistic characteristics. target. HoWever, Rubbert does not provide an aiming mark or
points of reference When the target is at a range such that it
BACKGROUND OF THE INVENTION does not ?t any of the apertures. The apparent spacing of the
target-spanning and aiming apertures can be changed by
[0003] Projectile Weapon aiming systems are discussed
varying the optical poWer of the ri?escope; hoWever, due to a
herein principally With reference to their use on ri?es and
limited amount of optical poWer adjustment available, the
embodied in telescopic sights commonly knoWn as ri?e
ri?escope of Rubbert is useful only for aiming at targets
scopes. It Will become apparent, hoWever, that projectile
Within a limited siZe range. For example, Rubbert describes a
Weapon aiming systems may include aiming devices other
ri?escope that can be adjusted for use in aiming at targets
than ri?escopes, and may be used on Weapons other than
siZed betWeen 14 and 40 inches in height. Attempting to ?t
ri?es, Which are capable of propelling projectiles along sub
smaller or larger targets in the apertures Would result in gross
stantially predeterminable trajectories, e.g., handguns, cross
aiming errors.
boWs, and artillery.
[0008] US. Pat. Nos. 6,032,374 of Sammut and 6,591,537
[0004] A factor that must be taken into account in long
of Smith propose reticles having a series of secondary aiming
range shooting is the curved trajectory traversed by a bullet or
marks spaced beloW a primary aiming mark at predetermined
other projectile as it falls from its initial trajectory While
intervals for compensating for bullet drop. After determining
traveling the distance from the gun to the target, i.e., “range.”
An aiming line of sight emanating from a reticle aiming mark or estimating an observed range, the shooter selects the sec
ondary aiming mark most closely corresponding to the
of a ri?escope rigidly af?xed to the gun is straight, and hence
observed range. The secondary aiming marks of Sammut are
the line of sight can intersect the curved trajectory only at a
evenly spaced, but a bullet’s trajectory is parabolic, so Sam
discrete range. At other ranges the projectile Will pass beloW
mut requires preliminary collection of ballistic data to deter
or above the aiming line of sight, necessitating the use of
mine the range corresponding to each secondary aiming
elevation adjustments for aiming. Elevation adjustments in
mark. The corresponding ranges determined by the collection
such ri?escopes are typically made by turning an adjustment
of ballistic data are applicable only for the ballistics of par
mechanism of the ri?escope to impart vertical movement of
ticular ammunition for Which data is collected. Furthermore,
optical elements (as described, for example, in US. Pat. No.
a shooter must either memoriZe the ranges that are empiri
3,297,389 of Gibson) or of the reticle (as described, for
cally determined or refer to a Worksheet Where the ballistic
example, in US. Pat. No. 3,058,391 of Leupold), so that the
data and corresponding ranges have been recorded.
aiming line of sight is accurately “sighted-in” at the range of
the target. To adjust for the effect of crossWinds, ri?escopes [0009] Smith purports to provide secondary aiming marks
also typically include a separate adjustment mechanism for for regular incremental ranges (typically 300, 400, 500, and
imparting horiZontal movement to the optical elements or 600 yards) in an attempt to eliminate the need, as With the
reticle. In yet other projectile Weapon aiming systems, the device of Sammut, to refer to ballistics data or to memorize
entire aiming device is adjusted relative to the Weapon via an the ranges corresponding to the secondary aiming marks.
adjustable sight mount. Adjustment of the elevation and HoWever, the ranges of the secondary aiming marks of Smith
Windage is time consuming and may require the shooter to are accurate only for a particular predetermined ri?e and
take his or her eyes off the target While manipulating the ammunition combination, referred to as the ballistic “factor.”
adjustment mechanisms. For ammunition having a ballistic factor different from the
[0005] There have been proposed numerous reticles and factor for Which the reticle is designed, Smith proposes to
ri?escopes designed to provide the shooter With a plurality of apply a decal to the stock of the ri?e or some other convenient
aiming marks for shooting at targets at various predetermined location for reference in determining the irregular ranges at
ranges, i.e., aiming marks producing line of sight/trajectory Which the secondary aiming marks can be used to aim the
intersections at various ranges. Some of these include devices ri?e.
for approximating the range to the target. These ri?escopes [0010] The present inventors have recogniZed a need for an
propose to eliminate the need to make elevation adjustments improved projectile Weapon aiming system for accurately
US 2009/0199702 A1 Aug. 13, 2009
compensating for ballistic drop and Windage for a variety of [0018] FIG. 3 is a vieW of a reticle in accordance With a
ammunition having different ballistic characteristics. preferred embodiment as vieWed through an ocular (eye
piece) of a ri?escope;
[0019] FIG. 4 is a vieW of the reticle of FIG. 3 including
SUMMARY OF THE INVENTION
dimension lines and reference numerals referred to in the
detailed description for describing the various features of the
[001 1] In accordance With preferred embodiments, a reticle
reticle;
for use in a projectile Weapon aiming system includes a pri
mary aiming mark adapted to be sighted-in at a ?rst selected [0020] FIG. 5 is a vieW of a reticle in accordance With a
second preferred embodiment, Which is adapted for big game
range and tWo or more secondary aiming marks spaced apart
hunting;
beloW the primary aiming mark along a vertical axis inter
secting the primary aiming mark. The secondary aiming [0021] FIG. 6 is a vieW of a reticle in accordance With a
third preferred embodiment, also adapted for big game hunt
marks are positioned to compensate for ballistic drop at pre
selected incremental ranges beyond the ?rst selected range mg;
[0022] FIG. 7 is an enlarged top vieW of the ri?escope of
for a selected group of ammunition having similar ballistic
characteristics. FIG. 1, shoWing detail of a poWer selector mechanism and
associated ?ducials used for varying the optical poWer setting
[0012] The reticle is preferably located proximate a rear
of the ri?escope to compensate for ballistic differences
focal plane of a ri?escope, betWeen a poWer-varying erector
betWeen tWo groups of ammunition; and further shoWing
lens assembly and an ocular of the ri?escope, so that angles
associated ranging ?ducials used, in cooperation With rang
subtended by adjacent aiming marks of the reticle can be
ing features of the reticle and the poWer selector mechanism,
adjusted by changing the optical poWer of the ri?escope, to
to estimate the range to a target of knoWn or estimable siZe;
thereby compensate for ballistic characteristics of different
[0023] FIG. 8 is a table listing ballistic drop data for a
ammunition and ?ring velocities. A set of ?ducial marks may
variety of ammunition at selected incremental ranges corre
be associated With a poWer selector mechanism of the ri?e
sponding to secondary aiming marks of the reticle of FIG. 5;
scope for prescribing at least tWo different optical poWer
the ammunition is grouped into tWo groups corresponding to
settings corresponding to at least tWo different groups of
tWo different optical poWer settings of the ri?escope of FIG.
ammunition. Each of the ?ducial marks indicates an optical
7, Which are selected to compensate for ballistic characteris
poWer setting at Which the secondary aiming marks accu
tics of the tWo groups of ammunition;
rately compensate for ballistic drop for a selected group of
[0024] FIG. 9 is a vieW of the reticle of FIG. 5 shoWing
ammunition at the preselected incremental ranges. Prefer
range-estimating features of the reticle being used to deter
ably, the groups of ammunition are chosenbased on empirical
mine an estimated range to a game animal of knoWn or esti
data, to group together ammunition having ballistic drop at
mated siZe; and
the incremental ranges of the secondary aiming marks that is
[0025] FIG. 10 is a vieW of the reticle of FIG. 3 shoWn
Within an acceptable error tolerance of a mean ballistic drop
aimed at a varmint at a knoWn or estimated range of 400 yards
of the group.
and compensating for a knoWn or estimated leftWard (right
[0013] In some embodiments, the reticle includes a set of
to-left) crossWind of 20 miles per hour.
Windage aiming marks spaced apart along at least one sec
ondary horiZontal axis intersecting a selected one of the sec
DETAILED DESCRIPTION OF PREFERRED
ondary aiming marks, to facilitate compensation in aiming for
EMBODIMENTS
the effect of crossWinds on the trajectory of the projectile.
[0026] Throughout the speci?cation, reference to “one
[0014] Methods of aiming are also disclosed, in Which the
optical poWer of the ri?escope is ?rst adjusted until it corre embodiment,” “an embodiment,” or “some embodiments”
sponds to the ballistic characteristics of the selected ammu means that a particular described feature, structure, or char
acteristic is included in at least one embodiment. Thus
nition. Thereafter, an ob served range to target is determined,
for example, by estimation or use of a range-?nding device, appearances of the phrases “in one embodiment,” “in an
before aiming With the secondary aiming mark that most embodiment,” or “in some embodiments” in various places
throughout this speci?cation are not necessarily all referring
closely corresponds to the observed range. In Windy condi
tions, one of the Windage aiming marks associated With the to the same embodiment. Furthermore, the described fea
selected secondary aiming mark can be chosen based on an tures, structures, or characteristics may be combined in any
observed crossWind velocity, to compensate for crossWind suitable manner in one or more embodiments.
effects at the observed range. [0027] Furthermore, the described features, structures,
characteristics, and methods may be combined in any suitable
[0015] Additional aspects and advantages of this invention
Will be apparent from the folloWing detailed description of manner in one or more embodiments. Those skilled in the art
Will recogniZe that the various embodiments can be practiced
preferred embodiments, Which proceeds With reference to the
accompanying draWings. Without one or more of the speci?c details or With other
methods, components, materials, etc. In other instances, Well
knoWn structures, materials, or operations are not shoWn or
BRIEF DESCRIPTION OF THE DRAWINGS not described in detail to avoid obscuring aspects of the
embodiments.
[0016] FIG. 1 is a side elevation vieW of a ri?escope [0028] FIG. 1 is a side elevation vieW of a ri?escope 10
mounted on a ri?e in accordance With a preferred embodi mounted to a ri?e 14 in accordance With a preferred embodi
ment; ment. FIG. 2 is a schematic diagram shoWing an arrangement
[0017] FIG. 2 is a schematic diagram shoWing optical ele of optical elements 16 of ri?escope 10, together With ray trace
ments of a ri?escope in accordance With a preferred embodi lines 18 indicating the path of light from an observed object
ment; (not shoWn) located to the left of the assembly of optical