Is the Weaver stance dead, supplanted by the obviously superior Isosceles stance?
[What is the Weaver stance]
Shooting lore attributes the handgun stance known as "the Weaver stance" to Deputy Sherif Jack Weaver, who developed it in 1959 while competing in "Leatherstrap" quick draw shooting competitions. Competing against others using predominantly unsighted hip-shooting methods, he quickly dominated the competitions which lead to acceptance of and praise for his stance. The stance consists of a non-dominant side forward boxing style foot position coupled with a two-handed grip in which the dominant hand and arm push the handgun forward while the non-dominant hand and arm draw the handgun back. This helps to "lock" the handgun in place, creating a stable shooting platform.
While attributed to Weaver, it is important to note that all the elements of Weaver's stance were taught by certain WWII combat shooting experts. Nevertheless, at the time of Weaver's "innovation," most combat shooting experts, favored a one-hand handgun grip which was, in fact a fixture of both Military and LEO training, as well as competitive shooting.
[Elements of the Weaver stance]
The key element of note regarding the Weaver stance is competing "push-pull" forces lock the pistol into a very stable platform which helps to mitigate recoil and minimize Arc of Movement when sighting.
[What is the Isosceles stance]
The "Isosceles stance" is most often thought of as a modern shooting stance. It features a two-handed grip on the handgun with both feet and shoulders placed evenly forward, presenting the torso and body parallel to the target. Both arms extend evenly forward from the shoulders, gripping the gun, forming an isosceles triangle with the chest. Many Military and Law Enforcement shooting experts now promote this stance over all others and its promotion by successful competitive shooters such as Jerry Miculek (sometimes referred to as "The Greatest Shooter of all Time"), who strongly advocates for its use, has ensured the wide acceptance, even ascendancy, of this shooting stance.
The stance is natural and the two-handed grip helps minimize Arc of Movement.
While the Isosceles is considered a Modern innovation, it is actually quite old. At the very least it pre-dates WWI and was well known up to WWII. During these earlier time periods this two-handed grip was considered inappropriate for combat pistol applications because the squared off body position made a larger target for return fire and exposed more of the torso and vital organs. This two-handed stance was also illegal in competitive shooting, which specified a one-handed grip, apparently in an effort to mimic combat shooting and promote the stance seen as more applicable to that. By WWII, this two-handed stance, while still considered inappropriate for most pistol combat ranges, was considered acceptable for long range, deliberately sighted fire due to its greater stability.
[The A B C of Rifle, Revolver and Pistol Shooting by Ira L. Reeves, 1913]
[Kill or Get Killed by Major Rex Applegate, 1943]
[One-Handed or "Off Hand"]
The standard one-handed stance, sometimes called either "off hand" or "target style," is composed of the shooter turning his body and torso in a "bladed" position such that the heels of the feet are often in line with the gun hand, or sometimes slightly turned and scribing a shallow arc. The gun hand is extended along the line of the shoulders and aimed at the target. For centuries, this one-handed shooting stance was considered the appropriate shooting stance for combat and even dueling.
This stance only requires one functioning, uninjured hand and minimizes exposed body area to return fire.
[Proper Combat shooting stance - The A B C of Rifle, Revolver and Pistol Shooting by Ira L. Reeves, 1913]
[Multiple Olympic Pistol champion and NYC police instructor Alfred Lane demonstrates proper Combat shooting stance - How to Shoot by Alfred P. Lane, 1914]
[What are the advantages of the Isosceles]
The Isosceles stance is very natural. It closely mimics the "startle crouch" response from a "fight or flight" adrenalin dump which is facing the threat, squared up, in a slight crouch, with both hands up. This makes it a natural choice for new shooters who may have had no other training which would supersede their instinctual reactions. For Military and Law Enforcement, this stance places the ballistic body armor ("bullet proof vests") in the most advantageous position to stop return fire while minimizing exposure of less protected areas of the body.
[The "Combat Crouch" from Cold Steel by John Styers, 1952]
However the Landis-Hunt "startle" Crouch is not the only instinctive startle reaction. While the "combat crouch" is one of the more common reactions, some studies conclude that there may be as many as 30 different startle reflexes to various stimuli, including the well known "turn away," flinch, and flinging both hands across the face horizontally and parallel to the ground. Therefor, depending on the shooter, it may not always be the most logical foundation to build a default shooting stance upon. In some cases, it may even be impossible.
[What are the advantages of the Weaver]
As mentioned above, the Weaver stance push-pull mechanics create a very stable shooting platform which minimizes Arc of Movement while sighting and helps to control recoil. This is conceptually the same system used when shooting rifle with a sling. The sling, particularly in the Military Loop Sling the Hasty Sling pulls the rifle in, locking it against the shoulder, again, forming a stable, push-pull relationship. The foot position, body position, and non-dominant elbow position for the traditional standing rifle shooting position are also very similar to the Weaver stance.
[Hasty Sling with M1 Carbine - Kill or Get Killed by Major Rex Applegate, 1943]
[Proper position with Military Loop Sling - The A B C of Rifle, Revolver and Pistol Shooting by Ira L. Reeves, 1913]
Besides the advantages of controling recoil and minimizing Arc of Movement, the push-pull mechanics locks the wrists and virtually eliminates "limp wristing." Semiautomatic handguns depend upon the slide reciprocating with enough energy to load the next round. Some new shooters and people under stress will fail to "lock" their wrists, keeping the muscles of the wrists "loose" while shooting. This acts as a kind of shock absorber during recoil which bleeds away needed kinetic energy resulting in the slide not having enough energy imparted to it to reliably cycle the handgun, causing failure to feed errors; a dangerous condition during a gun fight. The act of engaging the opposing push-pull mechanics forces the shooter to lock his wrists, near eliminating the likelihood of "limp wristing."
Further, the Weaver stance is nearly identical to the automatic fighting stance of trained boxers and martial artists, including many weapons styles.
[Fighter's Stance from FM 21-250, 1992]
The similarities of the Weaver stance to that of the stance automatically assumed by trained martial artists, riflemen, and experienced hunters makes it a very good candidate for inclusion into an "integrated system" of training. As with the Isosceles stance, the prior experience and training might make the Weaver stance the obvious choice for some shooters.
Finally, it is true that the Weaver stance tends to partially expose a less protected area of a Ballistic Vest, that part under the arm of the non-dominant "pull" arm. However, that is only a concern if the shooter is wearing body armor. For the time being, body armor is uncommon daily wear for those who are not in the Military or Law Enforcement which would remove that as a point in favor of the Isosceles stance over other shooting positions.
[What are the advantages of Off Hand]
One-handed, or "Off Hand," pistol shooting, as described above has a noted advantage of minimizing the amount of body exposed to return fire. This advantage was considered so important that the one-handed shooting stance was the dominant combat handgun shooting position for, literally, centuries.
[The Aaron Burr - Alexander Hamilton Duel]
However, as with the Weaver, there may be prior experience or training which could make the off hand stance more attractive to a shooter. One possibility would be expertise in archery. The stance used by an Archer or Bow Hunter is very similar to the Off Hand or "target" stance. The dominant is switched of course, but the Archer may be more comfortable assuming a stance so similar to what he commonly uses.
[Standard Archery Position for a left-handed Archer]
Fencers and experts in certain knife fighting systems may also be more likely to automatically fall into an Off Hand stance.
[Cold Steel - A Practical Treatise on the Sabre, by Alfred Hutton, 1889]
[Cold Steel by John Styers]
But everything comes with a price. Using only one arm means quicker muscle fatigue in shooting and the Off Hand position does the least to minimize Arc of Movement. It is the least stable and the most likely to allow limp wristing.
There is no "one best" shooting stance and other stances, the Weaver in particular, offer a great many advantages, particularly to trained martial artists who are not Military or Law enforcement. Use what stance fits best with your existing training, natural responses, and gear or load-out requirements.