US Patent No 11,333,459

Tuner Instruction Guide




NOTE: If you install 3 set screws, the unit will be more likely to vibrate loose.  ONLY USE 1 SET SCREW! - One (1) spare set screw has been provided. 

Prior to installing the Adaptive Tuning System (ATS), please make sure that the external weight is sitting slightly behind the front face of the internal mount. The internal mount has both a threaded and smooth section. The smooth section is the surface you will want the set screws to tighten against. If you thread the tuner too far back, and tighten the set screws, you may damage the threads.

  1. Tighten 1 set screw down making sure that the set screw is not contacting the internal mount threads. 
  2. Install the tuner on backwards to make sure that it sits directly up against the shoulder of your rifle. If it does not sit flush with the shoulder, REMOVE AND CONTACT US, DO NOT SHOOT WITH THE TUNER INSTALLED. If it sits flush, remove and install correctly with the open end of the tuner “sleeving” over your barrel and continue with Step 3.
  3. Install the tuner on your rifle by hand and tighten down by hand. Do not attempt to over-tighten the tuner as you may strip the internally threaded mount threads. If the outer weight rotates during install you can tighten the set screw more or install another set screw during initial install. – Make sure the tuner is threaded completely on and against the shoulder!
  4. Install your muzzle brake, suppressor, or thread protector of choice which will secure the tuner in place. All tuners have been plug gauged to ensure proper fit. If it does not fit, then your muzzle threads are mostly likely oversized or have carbon buildup. This is not uncommon and if this happens, you can attempt to clean your threads or if the ATS does not fit, it is possible that your threads are oversized. The tuner is nitrided and if your fitment is tight, you can put a small amount of grease on the tuner threads and thread it on your muzzle. Since the tuner threads are harder than your muzzle threads in some cases it can “clean” them up if slightly oversized. If the fit is too tight, DO NOT force the tuner.
  5. You have been provided 1 additional set screws to retain as spares, KSS recommends only using 1 of the set screws during tuning and usage as this creates the most consistency in the tuning process as well as securing the external weight. KSS suggest checking the set screw periodically especially in a competition setting.  When tuning, tighten the set screw as if you were finished tuning and ready to go shoot a match - GO SHOOT.



The following can be used as general guidance, but each rifle will vary. The tuner set screw must be tightened before shooting! Initial groups may be worse than groups without the tuner however if you follow the process outlined below, KSS is confident the tuners performance can help enhance your groups and consistency.

  1. Start with the tuner weight slightly in front of the face of the mount if using a brake and slightly behind the face of the mount if using a suppressor. Confirm Zero on your rifle and record your tuner starting position and fire some confirmation shots. You should have a target that allows you to shoot multiple groups at different aim points. Below is a link to a printable target you can download here that is similar to a .1mil grid
  2. The numbers on the tuner are for reference during the tuning process and do not indicate any defined start/stop/default positions and you do not need to start with the tuner set at zero.
  3. Rotate the tuner between each grouping of shots and secure the set screw as you would if you were going to a match. You should be able to recognize fairly quickly if it looks like its grouping using 2 shots to help limit ammo usage during tuning. See Hash guidance below.
    1. ATS Competition Tuner (Centerfire Rifles) – Increase 2 reference marks per adjustment cycle and fine tune between for most rifles.
    2. ATS Competition Tuner (Rimfire) - Depending on your barrel length and contour we have seen adjustment cycles range from 1 hash per movement up to 1/3-1/2 rotation. We recommend starting with 1-2 hashes between movements and determine if you see a noticeable change in downrange performance. The heavier and shorter the barrel may result more movement required between shots for tuning.
    3. ATS XL - Increase 2-3 reference marks per adjustment cycle and fine tune between for most rifles
  4. Take note of the location and dispersion of your group relative to your point of aim. You will see your groups move around your aim point as well as get bigger or smaller at certain locations. Do not adjust your zero during this process. 
  5. When you start to see similar group size / POI location, you can then fine tune between tuner locations. 
  6. If you are traveling for the shooting sports, and your rifle/ammo combo does not perform the same once at your destination, you can use the tuner to quickly get the rifle shooting again. We have found that the group can usually be tuned back in within a few hash marks in either direction.
  7. Example groups/nodes to look for during the tuning process can be viewed in the gallery at

Examples of the patterns you will see during the tuning process. If you only find 1 node, you should check the corresponding settings 1 hash left and right of the node you found as you may have landed in the middle depending on where you started. The #s on the tuner are for reference and it doesnt matter what number you start on. When you find 2 nodes beside each other, we suggest you set the tuner setting to the middle between the 2 nodes.


At this time the Adaptive Tuning System (ATS) only supports muzzle brakes that tighten and shoulder against the normal muzzle shoulder. Examples of these are the self-tightening styles via the use of a reverse jam nut or similar. Example muzzle brakes include, Patriot Valley Arms, Masterpiece Arms, American Precision Arms, Area 419 etc. KSS will be releasing a version(s) at a later date that supports other brake styles.


The ATS is a precision machined device and proper care should be taken to protect the threaded surfaces. There is no need to separate the 2 pieces. DO NOT Cerakote any of the threaded surfaces or the internal mount as it may cause fit issues as well as prevent the tuning weight from being able to be secured as designed. Damages caused by over tightening the set screws is not covered under warranty.

Returns will be accepted only if the device has not been used, is undamaged, or if ordered in the wrong specification. Buyer will be responsible for return shipping and will be credited once item is received and determined to be in 100% original condition.



Due to the liability and complexity of consumer reloading and muzzle threads variations, returns will not be accepted unless it is determined that there is a defect with the original product.