Do NOT Mount an Optic on Your Dagger Until You Read This

Mounting a red dot on a PSA Dagger Compact or Full Size (RMR cut) is not as simple as tightening two screws.

The screw depths on a Dagger slide are not symmetrical.

  • The right-side screw hole is shallow because it intersects the extractor plunger channel.
  • The left-side screw hole is deeper and allows a longer screw.

This means the screws are not interchangeable.

If the right screw is too long, it can interfere with the extractor assembly and cause cycling issues.
If either screw is too short, there will not be enough thread engagement to hold the optic under recoil.

Additionally, the optic must seat firmly against the front recoil lugs (bosses). Those lugs are designed to absorb recoil force. The screws are only meant to clamp the optic downward — not absorb recoil themselves.

When installed incorrectly, optics can:

  • Loosen under recoil
  • Shear screws
  • Strip slide threads
  • Lose zero
  • Damage the optic housing
  • Cause functional issues inside the slide

Follow the procedure precisely.

PSA Dagger Optic Mounting: Step-by-Step Guide

Step 1: Verify Correct Screw Length

Confirm you have the proper screws for your optic and your slide.

  • The right screw must be shorter.
  • The left screw must be longer.
  • Screws should not bottom out before clamping the optic.
  • The right screw must not protrude into the extractor plunger channel.

If unsure, test-fit carefully before applying threadlocker.

Step 2: Degrease Everything

Threadlocker will not bond to oil.

  • Clean both screw holes with alcohol (or acetone).
  • Clean both screws thoroughly.
  • Ensure the optic mounting surface is clean and dry.
  • Remove all oil, debris, and old threadlocker.

Everything must be completely dry before installation.

Step 3: Seat the Optic Properly

Place the optic into the slide cut.

Before tightening:

  • Push the optic fully forward against the front recoil lugs.
  • Ensure it sits flat with no rocking.
  • Maintain forward pressure while tightening.

The recoil lugs must carry the recoil load — not the screws.

Step 4: Apply Blue Threadlocker

Use medium-strength blue threadlocker (non-permanent).

  • Apply a small amount to the screw threads only.
  • Do not over-apply.
  • Do not use permanent (red) threadlocker.

Step 5: Alternate Tightening by Hand

Insert both screws and start them by hand.

As they begin to tighten:

  • Turn one screw about ¼ turn
  • Switch to the other screw for ¼ turn
  • Continue alternating

This ensures even clamping pressure and prevents one side from drawing down unevenly.

Step 6: Torque with a Proper Torque Driver

Use an inch-pound torque driver.

  • Continue alternating between screws as you increase torque.
  • Bring both screws up gradually.
  • Follow the optic manufacturer’s torque specification (commonly around 12–15 inch-pounds for many RMR-pattern optics).

Do not guess. Do not over-tighten.

Over-torquing can strip slide threads or damage the optic housing.

Step 7: Allow Threadlocker to Cure

Let the pistol sit undisturbed before shooting.

  • Allow proper cure time (typically 24 hours).
  • Do not rush this step.

Premature firing can break the bond before it sets.

Final Notes

On a PSA Dagger, mounting precision matters more than on many other slides because of the short-screw / long-screw configuration.

If installed correctly:

  • The optic will stay secure.
  • The slide will function normally.
  • Zero will remain consistent.
  • The recoil lugs will absorb the force — not the screws.

If installed incorrectly, failure is only a matter of time.