Apex Tactical Mount Holoson 509T to SIG P320 with SIG-LOC Optic Cut
 
Details:
This Apex Optic Mount is designed to securely mount the Holosun 509T to the slide of the Sig Sauer P320 Legion, P320 M17/M18 and other models featuring the Sig-LOC optic cut. It is machined from a billet of steel and Black Oxide finished.
 
The fully integrated rear sight in front of the optic acts as a gas shield to keep your optic glass cleaner longer and saves labor from needing to install a rear sight.
 
The integrated rear sight is setup to co-witness in the bottom 25% of the optic window. Requires a tall front sight for co-witness(Included). Two different sight height packages available. Select option based on barrel length (see below). 
 
The rear sight behind/after optic versions include a blast deflector that is not visible through the optic.
If you’re looking for this optic mount without backup iron sights, you can find it here: Apex 112-018-PRO. 
 
Expected Results: 
Designed to fit the slide of the Sig Sauer P320 with a SIG-LOC optic cut.
Cleaner optic glass due to the sight/blast deflector between the optic and breech
Works with the M17/M18 models with the factory Loaded Chamber Indicator 
Securely mounts the Holosun 509T to the slide
Thread Locking Patch pre-applied to screws (torque to 20 in-lb) 
Sights regulated for POA=POI at 10 yds with 115 Gr. Ammunition
 
Key Feature:
Both optic mounts include a gas shield, intended to keep your optic Objective Lense cleaner than it would be without the deflector.
BUIS in front of the optic: The Base of the BUIS is used as the gas shield.
BUIS behind the opic: The block sticking up in front of the optic is the gas shield.
 
For Use In These Guns
Works on the Sig Sauer pistols with a SIG-LOC optic cut including the P320 XFIVE Legion, P320-M17, P320-M18, P320 XFULL, P320 XCARRY, P320 XCOMPACT, and P320 XVTAC 
BUIS in Front/Before Optic: 
- BUIS in front of Optic; Choose 112-013-RS-450 for 4.7” or shorter barrels, such as the “M17/M18” Series pistols
- BUIS in front of Optic; Choose 112-013-RS-434 for the 5.0” barrel lengths, such as the Legion 
BUIS Behind/After Optic: 
- BUIS Behind Optic; Choose 112-320-RS-450 for 4.7” or shorter barrels, such as the “M17/M18” Series pistols
- BUIS Behind Optic; Choose 112-320-RS-434 for the 5.0” barrel lengths, such as the Legion
Does Not Fit These Guns
P200 Series slides
RX Classic Cut slides
RX-Pro Cut Slides
 
What's Included:
Apex Optic Mounting Plate with BUIS in front of or behind the optic. (Choose your Rear sight location in the pull down menu)
Optic Mount Screws with Pre-Applied Thread Locker
Front sight regulated to your barrel length (Choose your sight height by selecting your barrel length)