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Firearm Name and Sight List
Select or click on the Firearm Select button on the Data Entry page to open this Firearm and Sight module.
This database list is used to store individual firearm names and sight configurations that may be used in the ballistics and trajectory calculations.
After selecting a firearm sight configuration, the data may be entered into the appropriate configuration fields on the Data Entry page by clicking on the button.
To add a New Firearm Name to the database list, click the button. This will open the Add / Edit Names form.
Click the button to open a new, blank Firearm Name Record
Type in a unique descriptive name for the firearm and then press the key to fix the name into the entry field.
If the caliber name of the New Firearm is not in the Caliber Name List click the button and type in the correct caliber name. The Caliber Name should not be a decimal number such as is required for the various ballistic coefficient and trajectory calculations but should be a nominal description such as "30-06 Rem", "30-30 Win" or "357 Mag".
click the to fix the caliber name into the entry field.
Return to the Firearm and Sight Selection form and click on the button at the top of the page. This will open a new, blank record in the firearm database and open the drop-down list of firearm names where the New Firearm Name may be selected.
When the firearm name is selected the Caliber Name drop-down list will open and the caliber of the New Firearm may be selected.
Click the button to post the New Firearm Name and Caliber in the Arms Record Database.
After any load information has been entered for a firearm, do not edit or change the Firearm Name or Caliber Name as the software will not be able to locate and display any information associated with the firearm.
A Firearm may be removed from the database by clicking the button. This will delete the SELECTED FIREARM and all records associated with the Selected Firearm in all the Precision Records Databases.
Once the New Firearm Name and Caliber have been entered, go to the Sight Selection radio button panel and select the type of sight installed on the firearm. This will open the appropriate entry fields that are associated with the type of sight selected.
You may enter a brief name or description of the front and rear sights in the fields provided.
The next box opens if a telescope sight configuration has been selected . It is used to record the distance from the axis of the scope to the axis of the bore or "scope height in inches above the bore".
If a telescope sight configuration is selected, the amount of bullet strike movement per click must either be determined from the information supplied by the 'scope manufacturer or from actual experimentation and measurements and then manually entered into the value field. Usually the value is 1/4 inch, but not always, so care should be taken to arrive at the correct value.
An adjustable sight configuration causes the next three entry boxes to become visible.The first of which, is for the entry of the height, in inches, of the front sight above the axis of the bore.
The next adjustable sight configuration entry is the distance, in inches, from the rear face of the front sight to the rear face of the rear sight, whether it is a barrel sight, receiver sight, tang sight or vernier sight.
The "Graduations per inch" field requires some special consideration and is also essential for the accurate calculation of the sight adjustment tables. Some adjustable sights consist of a sliding ramp or bar and these adjustments or calibrations per inch are either printed, inscribed or can be measured with a micrometer gage.
Sights with a threaded screw adjustment may have the threads per inch measured and then multiply that number by the number of spaces formed by the markings on the screw head in order to determine the graduations per inch. For instance, a Thompson Center, Renegade Muzzle Loading Rifle adjustable rear sight uses an adjusting screw having 40 threads per inch with the screw head marked off into six evenly divided sectors, thus resulting in (6 X 40 = 240) 240 graduations per inch. This value of 240 graduations should be entered into the "Graduations per inch" field.
When this entry is made, an automatic calculation is performed, using the sight radius value and the graduations per inch value to calculate the movement of the bullet strike at 100 yards resulting from one graduation change of the adjustable sight. This calculated value is then auto-entered into the "bullet strike @ 100 yards" entry field.
If a Vernier type sight is used, the number of graduation marks per inch on the staff should be entered. The software will automatically calculated the further division of the graduation marks into points. (1/5 of each graduation mark) (20 graduations per inch on the staff results in 100 graduations per inch in the final Vernier Sight calculations) ( For Vernier Sights, the value in the field that displays the bullet strike @ 100 yards display may be divided by 5 to arrive at the amount of strike change per point adjustment)
When a Fixed Sight configuration is chosen, the only sight value required is the height of the front sight above the centerline of the bore. An accurate measurement can easily be made by using a caliper to measure the distance from the bottom of the barrel to the top of the sight and then subtracting one half of the diameter of the barrel where the sight is attached.
The Firearm Groove Diameter field records the distance value from the bottom of a rifling groove to the bottom of the opposite groove in the barrel. This is normally the diameter (in inches) of the bullet fired from the firearm. ie 30-06 = 0.308", 45 Cal = 0.452", etc. Slugging the firearm bore and measuring the slug will reveal the exact bore diameter.
After the entry fields all have the correct values, click the button. This will enter the name of the firearm and the correct sight configurations into a permanent record that may then be retrieved and sent to the Data Entry page to be used in the Ballistics and Trajectory calculations.
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