Here is what the Army Marksmanship Unit Manual says about grip:
C. GRIP.
The proper grip is one which provides the shooter with the maximum control of the weapon. To maintain a natural sight alignment, he must hold the weapon firmly and be able to apply positive, straight to the rear pressure on the trigger that will not disturb sight alignment.
1. Uniformity: For maximum control, all of the requirements for a proper grip must be uniformly applied at all times.
2. Requirements: The proper grip on a pistol is one that meets the following requirements:
a. The grip should be such that the front and rear sights will stay in natural alignment without any extra effort to maintain the relationship. Without this feature, there will be a tendency for the front sight to move over to one side of the rear sight notch, or be moved above or below the horizontal surface of the rear sight. Sight alignment, quickly regained after recoil without the need for correction, speeds up recovery and improves timed and rapid fire control. Maintaining sight alignment should be an effortless action before the next shot. Positive trigger pressure can be applied if the sight alignment is being maintained without effort. Sight alignment is easier to maintain if no adjustments are necessary such as moving the wrist or head.
b. Grip the pistol firmly enough while firing a shot so that shifting or slipping of the grip will not cause loss of control of the pistol. Recovery from recoil for the next shot in sustained fire is seriously hampered by the loss of sight alignment. The trigger pressure under these conditions is usually reluctant and timid. Unless the proper grip can be renewed quickly, (next to impossible in the middle of a timed or rapid fire string) maintaining sight alignment during the application of positive trigger pressure is a difficult operation. The tighter the grip, short of setting up a tremble, the better the control. The degree of pressure that should be exerted in gripping the pistol is determined by the condition of the muscles that do the gripping. Frequent practice, experience and certain exercises promote a strong grip and have a bearing on when a tremble will begin.
c. There must be no change in the tightness of the grip because a variation of gripping pressure will adversely effect sight alignment. Any degree of tightening or loosening of the grip from an established grasp will cause the sights to move out of alignment. The pressure of the grip must remain constant. It cannot be increased or decreased as trigger pressure is being applied because sight alignment will be altered.
d. The trigger finger should apply positive pressure on the trigger as an independent action, completely free of the other muscles of the shooting hand. The trigger finger should not touch the stock or the frame of the pistol because of the added friction and drag on applying trigger pressure. Dry fire a few shots watching the front sight carefully. If the front sight moves at the instant the hammer falls, reposition the trigger finger to the left or right, up or down, on the face of the trigger. Repeat the dry firing and adjusting the position of trigger finger until the release of the hammer causes no movement of the front sight in the rear sight notch.
e. There can be no variation in the grip from one shot to the next, from one series of shots to the next, from one day's shooting to the next, ad infinitum. In the final analysis, there is only one correct grip for each shooter. Each type of pistol, caliber . 22, caliber . 38, caliber .45 has its peculiarities and the shooter must adapt to each. The proper grip can be discovered through trial and error, practice and analysis. It must become, by extensive use, a familiar operation that eventually can be assumed without much difficulty. When the experienced shooter checks his grip out before shooting, it seldom needs adjustment. One of the frequent variations of grip that plagues new shooters is the grasping of the pistol grip with the hand slightly displaced to the right or left from the normal. As a result the placement of the trigger finger on the trigger will be different, thereby jeopardizing the requirement that the trigger be pressed straight to the rear.
f. The grip must be as comfortable as possible. The muscles of the hand and lower arm, after sufficient time has passed for the hand to become accustomed to the added stress, should experience little discomfort from the way the pistol is placed in the hand. If the grip is awkward and possible cramping and the hand muscles continue to tire easily, look for another solution or use an exercise device to strengthen the hand. To avoid the formation of painful, blisters, calluses and cracked tissue, reduce the tendency of the skin to stretch. Tautly stretched skin may also pull or exert force on the pistol frame in such a way as to cause eight alignment deviation. An equalization of the stretching of the skin and muscles of the gripping hand is paramount. Straight-in contact should exist between the skin of the fingers and palm and the surfaces of the frame and grips when the gripping pressures are brought to bear; not a sideward, sliding or grazing pressure.
g. The force of recoil must be controlled by being transmitted straight to the rear into the shooting arm. Recoil against the base of the thumb, which causes the weapon to twist in the hand, will allow a shift or grip and/or a bending of the wrist. Either event jeopardizes quick recovery from recoil in timed and rapid fire. The pistol should be held by being gripped normally, not by a choking grasp that endeavors to press on the stock in an all enveloping grab. The best points of pressure to hold the sight in alignment are the semi-flat grips on each side of the frame. However, the gripping hand cannot exert equal pressure on each of these surfaces simultaneously and such pressure would not overcome the effect of recoil. Therefore, the obvious pressure points of the shooting hand that will channel the effect of recoil straight to the rear and allow relative ease in maintaining sight alignment are: the middle bones of the three lower fingers, the base of the thumb high on the stock, the depression on the center of the heel of the hand, and last, the base joints of the four fingers along the upper palm. The primary pressure points on the .45 caliber pistol are the front surface of the grip and the mainspring housing-grip safety surfaces. The secondary points are: high on the left side of the stock near the slide lock and the forward curve of the right grip, each of which have to have gripping pressure applied equally to prevent loosening of the over all grip, and to maintain sight alignment. h. Holding the grip too long without an occasional relaxation will result in early fatigue. Fatigue destroys control. Excessive force of gripping for control of the pistol assures that fatigue will exist if the gripping power of the hand is weak. Undue fatigue in the muscles of the hand and forearm will also cause erratic application of trigger pressure. The tremble level is lowered to a point where the shooter cannot hold the pistol still, even for a few seconds, while trigger pressure is being applied.
3. Method of getting the proper grip: The proper grip must conform to all of the foregoing requirements plus it must be a hard grip and it must be adapted to the hand of the individual shooter.
NOTE: FOR THIS INSTRUCTION IN OBTAINING THE PROPER GRIP, THE WEAPON IS THE .45 CALIBER SERVICE PISTOL. THE FOLLOWING STEP-BY-STEP SEQUENCE WILL PROVIDE THE PROPER GRIP:
a. With the non-shooting hand, pick up the pistol by the barrel and of the slide, being careful not to mar the blackened sight and keep the muzzle pointed down range.
b. Spread the index finger and thumb of the shooting hand apart to form a "V", with the thumb held slightly lower than the index finger.
c. Bend the wrist slightly downward to obtain proper angle of contact.
d. Fit the pistol into the "V" of the thumb and index fingers by seating the grip safety straight and firmly into the loose "web" of akin in the "V".
e. Press downward on the barrel to pivot and push the mainspring housing firmly against the inside of the bulge of flesh at the base of the thumb and into the depression in the approximate center of the heel of the palm.
f. Stretch the fingers forward, letting the trigger finger come to rest flat against the pistol frame just above the trigger guard. Safety dictates the trigger not be contacted at this time.
g. The lower three fingers should come to rest closely touching each other, with the center bone of each finger resting on the curved front surface or "front strap" of the receiver. Little or no pressure should be exerted on the finger tips extending around the front strap to the surface of the left handgrip. Pressure exerted on the front strap by the little finger should be lighter than that brought to bear by the middle and ring fingers. Too much pressure with the little finger may cause the muzzle to depress slightly, resulting in the front sight aligning low in the rear sight notch.
h. The thumb should be raised to a level higher than the index or trigger finger. Only the joint at the middle of the thumb is high against the stock in the vicinity of the slide safety. The end of the thumb is turned up and away from the stock as it has no function. Pressure exerted on the aide of the pistol by the end of the thumb has a tendency to disturb sight alignment. The thumb should not exert great pressure on the aide of the pistol as early fatigue will result. Only required substantial supporting force should be exerted to hold the weapon firmly in place in the shooting hand.
i. A controlling grip can be affected by the three lower fingers directing primary pressure on the front strap straight to the rear, pressing the mainspring housing and grip safety firmly against the side of the center depression and the heel of the palm at the base of the thumb, and the loose flesh in the "V" of the thumb and index finger, respectively. This can be compared to a vise with the inner surfaces of the palm as the stationary jaw of the vise and the three lower fingers pressing on the front strap of the pistol as the moving jaw.
j. The non-shooting hand should be used to adjust the "fit" of the pistol into the shooting hand. A slight rotation of the weapon in the gripping hand as it is alternately gripping and releasing will allow the equalizing of a forceful grasp. The gripping hand must reach around to the right far enough to allow the trigger finger to reach into the trigger guard and also to position itself on the trigger at the exact point at which the trigger pressure can be applied straight to the rear. According to the size of the hand, the trigger finger will apply pressure with the tip, ball of the first section or the crook of the first joint or elsewhere. The primary concern is not what portion or spot along the trigger finger is the standard point of contact, but at what spot on the finger you can bisect the trigger, press straight to the rear without disturbing sight alignment.
k. When the "fit" is correct, remove the trigger finger from the trigger, free the pistol from the non-shooting hand and tighten the grip with great force until a tremor is noticed. Release a small percentage of this gripping pressure immediately, enough so that the tremor disappears and leaves the shooter with a hard, solid grasp that will result in absolute control. The tighter the grip, the better the control. The shooter is now exerting correct pressure for maximum recoil control.
4. Checking For Proper Grip: The proper grip is a natural grip that will meet all the requirements in paragraph 2, above. To assure a proper grip, it should be checked against the requirements. A deciding factor in knowing whether your grip is proper is one of familiarity. By use of the proper grip innumerable times, a flaw is immediately sensed.
a. To assure the sights will stay in alignment, the following test is made: extend the shooting arm and observe the sight alignment. If the front and rear sights are out of alignment, grasp the barrel with the non-shooting hand, loosen the grip sufficiently to slide the pistol in the hand, rotating it slightly away from the direction of error in sight alignment. Re-grasp the pistol firmly and extend the arm. Check the alignment without an effort being made to align them by wrist or head movement. If the alignment is natural, you may check for maintenance of sight alignment. With the arm extended, close the eyes, raise and lower the arm and settle. Open the eyes and observe. If the alignment has deviated, reposition the pistol in the shooting hand and repeat the closed eye test until natural alignment of the front and rear sights is achieved and maintained. During shooting, a constant check should be conducted of the tendency of the sights to continue to align themselves. The grip obtained at the beginning of shooting will not necessarily remain correct because the jolting recoil and build-up of fatigue will require correction to the grip to maintain sight alignment.
b. To check for a grip firm enough to prevent shifting after making sure the pistol is unloaded, have the coach bump the pistol rather forcefully, up or to the aide with the heel of his hand. Also, have the coach grasp the pistol by the barrel and make an effort to tear it from your grasp.
c. To check for variations in tightness or correctness of grip, it is best to dry fire a few shots before live shooting starts and watch for slight variations in sight alignment.
d. Checking for independent trigger action should be accomplished before shooting by a visual check of the trigger finger clearance from the grip. Check by dry firing to detect any drag or undue friction noticed in the trigger. Also, check for a sympathetic tightening of the muscles of the hand as trigger pressure is applied. This can cause as much disturbance of sight alignment as the failure to press the trigger straight to the rear.
e. The rapid onset of fatigue and soreness of the shooting hand is usually the result of an incorrect grip.
f. Checking for straight to the rear recoil directly into the shooting arm and shoulder can best be done in practice with an unloaded pistol by having a coach or team mate stand in front of you and forcefully and abruptly push against the muzzle of your tightly gripped pistol driving it straight back toward your shoulder in simulation of recoil action.
5. Aids to Developing a Good Grip: The great pistol shooters have: strong hands and a hard grip; a method of gripping without change unless analysis dictates a change that will improve it; a different grip mastered for each shape of stock or different type of pistol; molded, shaped or custom grips, that fit perfectly; and if they use powdered rosin or a like substance, they use it every time the hand becomes moist before they grip the pistol.
a. The "top guns" have a grip like a vise. Exercise devices such as rubber balls, spring grip builders, etc. will develop a strong grip. Exercise devices require constant use. Another approach, to reduce reliance on artificial exercisers, is to engage in work or a sport that places demands on your manual strength and dexterity, for example, chopping wood, digging in the garden, using hand clippers on the hedge; playing tennis, baseball, ping-pong, etc. Use of the hands in meticulous work also develops an exacting touch and coordination that is valuable to the pistol shooter.
b. Never thoughtlessly change your grip. A correct grip is a precious commodity. It evolves from much hard work, thinking, and planning, plus painstaking analysis. Each satisfactory grip found among the better shooters comes from trial and error. The good grip that is the end product of much effort should not be changed except when sharply critical analysis dictates a change that will improve it. The shooter who is desperately changing his grip hoping that he will chance upon the right solution will generally lower his scores. In the event that a better score is fired under these conditions it comes on an occasional basis with no tangible reason for the improvement. Analysis and trial, in a never ending quest to improve your marksmanship, is the answer.
c. A modification of the shooter's proper grip is necessary on different types of pistols. The firmness of the grip remains the same for all calibers and types of pistols and revolvers, but nature of the grasp must correspond to the shape and size of the grips in meeting all the requirements of the proper grip. For example, the caliber .22 grip is sometimes found to be smaller in circumference than a caliber .45 pistol. In this instance, the reach of the lower three fingers may extend further around the stock, resulting in one of the primary pressure points (the middle bones of each of the three lower fingers) coming to rest beyond and partially around to the left side of the front strap. Pressure exerted would not be straight to the rear. As it is fully applied in the normal grip, it would no doubt effect the natural alignment of the sights. Also, shooters with small hands have trouble with stocks of varying sizes. One example is having to compromise, due to a short trigger finger which can reach the trigger only with the finger tip, between a straight to the rear trigger pressure and the best position of the pistol in the shooting hand that tends to give natural sight alignment.
d. Shaped, molded or tailored custom grips are required to fit perfectly. Fitted grips are primarily used to help the shooter who can't consistently duplicate the proper grip when using standard factory grips. The individual shooter must first decide what features and characteristics of a shaped grip suit his hand. Stocks can be made to fit exactly, but it is a difficult job. Only an experienced shooter is capable of knowing what he actually needs in a custom grip, because only he knows what his proper grip looks and feels like.
e. Powdered rosin dusted on the hand can help to maintain a solid, controlling grip but it is not absolutely necessary. Normally, a strong hand and the checkering and stippling on the stocks and metal surfaces is sufficient. In hot weather when the hand may perspire or a hand that becomes wet in the rain may cause slippage, powdered rosin or a like substance, that will temporarily dry the skin of the palm and fingers, is then justified.
In the final analysis, there is only one correct grip for you. It is one that is firm; affords the individual shooter the maximum degree of control over maintaining sight alignment and allows positive, straight to the rear pressure on the trigger without disturbing sight alignment.
