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Was: $34.99
Now: $21.99
(9 reviews) Write a Review
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After several requests for a better trigger from the Sphinx SDP Compact pistols from customers. We finally took action and created a kit that not only makes the Sphinx SDP Compact a better combat pistol but now a contender for competition shooting. Unlike other kits on the market which have poorly made springs to retain safe operation of the firing pin during a drop incident. Our kit redesigns the the springs inside the Sphinx Sub Compact to allow for a proper reduction of hammer spring pressure felt when you pull the trigger, without compromising the safety of the pistol. We recommend you test your ammo with the shim installed and not installed to understand the hardness of your primers. With the shim installed we have had 100% success in firing all rounds we tested including the hardest we have found. With shim removed hardest primers will have issues firing. Trigger pull will be significantly reduces in both SA and DA possible with our kit, finally making it ready for fast accurate shots on target.


**Beware of other companies who are trying to knock off our kit for a little less money and sell you a product that is not made to the same standards as our the original "Sphinx Enhanced Trigger Kit" or "B&T ENHANCED TRIGGER KIT" high quality standards. Our products are made to the same Sphinx standards and made in the USA - not China, Just because they look similar and use our product name - it is not the same ALL.**




WITH SHIM DA IS 8LB AND SA IS 4LB 2OZ (Measured on a stock SDP subcompact)

Kit includes:
Reduced firing pin spring
Reduced Hammer spring 
Spring seat shim

Ammo's tested and verified working:

Federal American eagle ball 115gr and 147gr
Tula (had issues with purple spring and some green)
Sig V Crown
Hornady Crit Def and Duty
For installation of this kit we have created a video to assist you here ->
*We are not liable for any use in ccw application.
***We recommend all trigger kits be installed by a gunsmith.
No shipping outside of the USA due to ITAR

Please note- DISCLAIMER: “Sphinx” may be a federally registered trademark of Kriss USA, Inc. Neither Modern Weapon Systems (MWS) nor this website are affiliated in any manner with, or otherwise endorsed by, Kriss USA, Inc. The use of “Sphinx” "SDP" "SUBCOMPACT" "COMPACT" "ALPHA" "DUTY" on this page is merely to advertise the sale of Sphinx pistol aftermarket parts, or accessories, manufactured by Modern Weapon Systems

9 Reviews Hide Reviews Show Reviews

  • 5
    Have not installed yet but looks great

    Posted by Curtis Edmondson on Oct 20th 2021

    Very good upgrade

  • 5
    Sphinx Subcompact Spring Kit

    Posted by Chris on Aug 26th 2021

    High quality and excellent service are the reasons I continue to purchase from Ian and his shop!

  • 5
    Hammer spring

    Posted by Terry on Oct 17th 2019

    What I was looking for. Not much out their for subcompact Sphinx 9mm. Happy to find them at your web! Thank you! Still looking for sighs for subcompact?

  • 5
    Sphinx SDP Subcompact Kit

    Posted by Chris on Jun 26th 2018

    Fantastic and simple spring kit that vastly improved the trigger on my daily carry without any reduction in reliability!

  • 5
    Subcompact Spring Kit

    Posted by Rob on Jan 2nd 2018

    I bought one of these kits with hopes of a little improvement in the Sphinx subcompact trigger. I was amazed at what a difference it made. Thanks for making a great and affordable upgrade.

  • 5
    Sphinx Subcompact trigger upgrade

    Posted by RP Ruggiero on Dec 27th 2017

    Video made the install a breeze! Trigger feels better, can't wait to test it out! thank you.

  • 5
    Sphinx Subcompact Trigger

    Posted by Bruce Y on Nov 25th 2017

    Reduced SA to 4.5 pounds and DA to 7.5. Excellent.

  • 5
    Spring Kit

    Posted by Chuck Emary on Nov 1st 2017

    The product arrived in a timely manner. I followed both videos and had only minor issues getting everything installed. The decrease in trigger pull for double action is amazing! So far no issues whatsoever. I would definitely recommend this kit.

  • 5
    Sphinx Subcompact spring kit and trigger release spring kit

    Posted by Pete Carroll on Sep 17th 2017

    Had both kits installed by MWS after purchasing Sphinx Subcompact from them. I already own a Sphinx compact (one of the finest pistols I have shot) and I am waiting to install the spring kit on the compact. Just waiting for Brownells for the correct punches. Excellent how to videos posted under the products. I am very excited to see what this company has for me in the future. Well done!

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