Top Precision On Pneumatic Competition Pistols

Juan Moratto

Not always a pneumatic pistol brings all its potential, in spite that it could be of a brand of first, such as Steyr, Morini, Pardini, Hammerli, etc. if its propulsion velocity of the pellet isn´t correctly regulated.

From the factory, they are sent with a test target onto which is detailed the ammunition used (for example RWS) and the pellet diameter (4.50mm, 4.49mm) with which the best group was reached.

This test is done under ideal and foreign conditions, without taking into account the local climatic factors, such as the temperature or the atmospheric pressure. It is a test that guarantees a minimum group in a certain and specific moment. Moreover, the pistol is sold regulated such velocity, that assures an optimal grouping.

The pneumatic pistol shooter must take into account various factors that affect his groups:

1. The climate factors of the zone or region where he shoots, affects the output velocity of the pellet, independently of the factory adjustment.

2. The quality and quantity of use that the gun suffers affects this adjustment, for settling of the valve, the pre-chamber o´rings and the settling of the hammer and spring springs.

3. The pellets that you use, at least, must be identical to the ones used at the factory test (brand, model, diameter and preferible lot number), if not, they wouldn´t group in the same way as the test target.

Moreover:

Not always the pellet launch velocity is the ideal for the shooter to group optimum at the target, lot of times it is necessary to find a higher or lower velocity, according to the applied shooting technique of the shooter (slow and static or fast and dynamic, for example).

For all of these, it´s always necesary to make an adjustment in the pellet velocity, regulating and tuning adequately the amount of propellent (gas or air) that is freed from the cylinder (or pre-chamber) each time that a shot is done. The objective is that the obtained grouping never exceed the center diameter, or best, the diameter of the inner ring at the X-ring, in order to give more chances to the shooter in case of mistakes in the shooting procedure or execution.

With respect to the ideal output pellet velocity, if normally the competition pistols launch it in the 140-155 meters/second range (500 fps), independently of the air/gas charge pressure of the cylinder, generally comprised between 200 to 300 bars, it´s not a relevant data because the usefulness of a fast or slow gun depends on each shooter in particular.

As more slowly flies the pellet, less recoil is perceived by the shooter and, when more fast, bigger is the perceived recoil.

Because the main problem of the pneumatic shooting resides in the pellet relative slow velocity (with respect with the firearms or high power rifles, for example), which resides a very long time inside the barrel, affecting the accuracy, always was searched for pistols capable of giving an faster muzzle velocity.

When more fast gets the pellet out of the barrel, less possibilities to make a parallel error at the target (the angular error is the same). The recoil problem was solved adding compensators and ported barrels to the pistols, facilitating, in this way, using very fast pistols with near no perceived recoil (as the Steyr LP10 and the Feinwerkbau P34).

The procedure for correctly adjust a pneumatic pistol for obtaining its best possible performance is the following:

1. Select the best pellet that you could obtain and use for competition: the brands and ideal models for competition are: RWS Pistol Match, Lapua Pistol Match, H&N Finale Match or Pistol Match, Frankonia Sport, Varga Pistol Match, JSB Pistol Match, and between them, the models identified as "high-speed". Preferible they must be chosen into the diameter that was employed in the test target, or one sligtly small.

2. Go to the shooting range with a big white or yellow sheet of paper of good size, a screwdriver and the pistol instructions manual.

3. If the shooting range don´t have proof test instalations, a gun support, ramson rest or similiar for your gun, you must take with you any system (sand bags, gun craddle adequately protected for not ruining the pistol) that assures you that the gun will be quietly (really statically) IN ALL THE SERIES YOU´LL GO TO SHOOT.

4. A Scope for verifying the impacts.

This procedure is appliable to ANY pneumatic pistol, gas or air, for competition equipped with a screw for regulating the volume of propellent for pushing the pellet through the chamber and the barrel.

5. Fix the pistol to the craddle or support firmly, alinging it with the sheet of paper that must be fixed to the shooting distance: 10 meters.

6. Put all the tools and pellets over the table for avoiding any kind of alteration, movement or disturbing that could affect the gun. Of course, the shooting range must be covered and aislated from light (preferible artificial light) and wind, so to maintain always constant conditions.

7. Choose a kind of pellet and do 5 shoots very, really very carefully. Verify the group agains the competition target. Displace or move the paper and turn the propellent launch adjusting screw ONLY 1/12 th. in its circular movement (for example, if any point of the screws is oriented towards the 12 hour position, turn it clockwise till the our 1 in the clock, or five minutes, it´s the same).

8. Move the white or yellow sheet of paper and do, with the same pellet, 5 shots more, again very carefully. If the group is smaller, you could continue increasing the launching pellet velocity till the moment it start to get greater or more disperse, in this moment you MUST return to the last adjustment that gave the best possible group with the maximum possible velocity.

9. If the group got greater, you must displace the regulating screw anti-clockwise to its original position and, again, reduce it 5 minutes anti-clockwise, if the group becomes smaller, make another reduction in the velocity and verify again. It is not convenient to reduce de velocity any more because it will affect our precision at the moment of making the shot.

10. If, in spite of these adjustments, you couldn´t equal or surpass the factory group, you must opt for a differente brand and/or model of pellet.

So, the gun is now calibrated for the BRAND AND MODEL OF THE PELLET THAT YOU MUST USE FOR WINNING COMPETITIONS, the ones that you will use for training, probably cheaper, almost never could reach this grouping, but this is not a problem because you will use them for training and for correcting execution mistakes. Of course, what is something ideal, you could use the same pellet in both cases: for training and competition.

Once obtained the ideal adjustment, generally, you must repeat it once a year, because the settlement of the mechanisms.

The results will appear surprisingly in front of your eyes: at the moment of shooting with a more accurate gun and more fast, you will gain immediatly a lot of points, specially those points that were lost for parallel errors (a nine that in reality was seeing as a perfect center).

The competence or match day, the shooters are usually more nervous and with more tension, so they feel that they are more "moved" or not stable than usual, a faster muzzle velocity will give them more confidence for releasing the shoot in spite that the weapon stay moving. If all was well done, the shoot will be a center, a ten, without doubt.

Take into account that all international and olympic shooters, adjust their pistols in this way. Since that, we could think sometimes that their qualifications and scores are very difficult to reach in spite that we use the same equipment. Not always is in such way: an excellent and "top" pistol bad regulated or using bad quality pellets gives no advantage over a pistol of basic level or very less quality.