Creedmoor Sports Shoulder Datum Bar
The Shoulder Datum Bar is designed to allow you to use the Creedmoor Sports Shoulder Datum Tool with a dial indicator and a granite comparator stand. This provides a stable, quick, and accurate measurement of the shoulder. This kit is compatible with most dial indicators that have a removable foot that is internally threaded for 4-48 UNF.
Kit Contents:
- 3/32 Allen key
- 4-48 x ½ socketed cap screw
- Shoulder Datum Bar
You will need:
- Creedmoor Sports Shoulder Datum Tool
- Dial indicator with a stem threaded for 4-48
- A stand for the dial indicator and reference plate, such as the Creedmoor Sports Granite Comparator Stand
Setup:
- Remove the indicator foot. This should unscrew by hand but sometimes can be a little tight. If needed, wrap the foot in a cloth and use a pair of pliers to gently grab the foot and break it loose. Then unscrew by hand.
- Rotate the Shoulder Datum Tool so the appropriately sized hole is in the 6 o’clock position and install the bar at 12 o’clock. Use the two thumb screws provided with the Shoulder Datum Tool to clamp it onto the bar.
- Using the Allen key, install the socketed cap screw and thread it into the dial indicator stem.
- Rotate the Shoulder Datum Tool so that it faces you and tighten the screw. Be careful not to overtighten as that can damage the indicator.
- If the indicator was not mounted to the stand, go ahead and mount it to your stand following the manufacturer’s instructions. Use the bottom of the bullet comparator to square the dial indicator to the surface plate.
Use:
- Lift the stem of the indicator with the Shoulder Datum Tool attached.
- Place the case under the indicator and lower the stem so it sits on the case shoulder.
- Make any necessary adjustments to the dial indicator so that it reads zero.Place a second case under the indicator.
- The measurement difference between the first and the second case is your comparative measurement.
