Blast Pack for Ruger® Mark IV and 22/45


(12 reviews) Write a Review
0.30 LBS

Out of stock


Blast Pack for Ruger® Mark IV™ and 22/45™ Instructions


The Blast Pack for Ruger® Mark IV™ and 22/45™ is a match set ONLY - DO NOT use any other brand of sear and hammer with the TANDEMKROSS “Blast Pack” for Ruger® Mark IV™ and 22/45™


At a glance:

  • Radiused sear and hammer interface for clean, crisp, and repeatable trigger pull. 
  • Approximately 2–2.5lb trigger pull (results may vary)
  • Neutrally balanced, drop-safe sear
  • Highly impact and wear resistant, heat treated, S7 hardened tool steel for long-lasting, optimal performance

The TANDEMKROSS “Blast Pack” is a serious upgrade for all Ruger® Mark IV™ and 22/45™ owners! 


Our innovative redesign of the fire control system safely reduces trigger pull weight for a performance boost and increased reliability! The lubricant coating on the hammer and sear provide a consistently smooth hammer-sear interface right out of the box. Our lightweight hammer also moves at a higher velocity leading to reduced lock time.


The Blast Shield Magazine Disconnect promotes proper magazine alignment for consistent and reliable feeding. It also protects the hammer and sear from debris and build up for easy maintenance.


Perfect for competition shooters, small game hunters, or any rimfire enthusiasts, the [TK] Blast Pack for Ruger® Mark IV™ and 22/45™ will bring your .22LR plinking to the next level!


This Kit Contains:


Thunder Hammer and Lightning Sear

  • Safely and reliably reduces trigger pull weight
  • Provides consistently clean and crisp trigger pull
  • American-made and guaranteed for life

Blast Shield Magazine Disconnect

  • Allows for safe removal of the magazine disconnect
  • Facilitates proper magazine alignment
  • Shields sear and hammer from debris

BLAST past the competition with the BEST fire control system on the market; the TANDEMKROSS “Blast Pack” for Ruger® Mark IV™ and 22/45™!


Support Models:

  • Ruger® MKIV™ Standard
  • Ruger® MKIV™ Hunter
  • Ruger® MKIV™ Target
  • Ruger® MKIV™ Competition
  • Ruger® MKIV™ 22/45™
  • Ruger® MKIV™ 22/45™ LITE
  • Ruger® MKIV™ Tactical
  • Ruger® MKIV™22/45™ Tactical 

Looking for the Ultimate fire control upgrade? Include the TANDEMKROSS Victory for unmatched performance! Find the full package in the Ultimate Trigger Kit for Ruger® Mark IV™ or Mark IV™ 22/45™

Don't forget, all TANDEMKROSS products are Made in the USA and come with a LIFETIME guarantee!

WARNING: This product can expose you to chemicals including chromium, which is known to the State of California to cause cancer. For more information go to

12 Reviews

  • 5
    TK trigger and blast pack

    Posted by Mike Kohler on 9th Sep 2023

    Nice kit(s), bought them separately. Trigger was about a 25% improvement over the Ruger factory trigger. The TK hammer and sear were huge. Nice light pull and NO creep. Utube videos were great for assembly. Great products.

  • 5
    Blast Pack

    Posted by Tink on 3rd Sep 2023

    Every MKIV needs this upgrade. Trigger is now very smooth and consistent. Accuracy improved dramatically.

  • 5

    Posted by Craig on 2nd Jul 2023

    Totally worth it. The blast pack along with the Victory trigger makes a good gun great.

  • 5
    Order # TK- 332470

    Posted by Solle on 9th Nov 2022

    Very good product, easy assembly thanks to the video on your website. very good result at the shooting range. Thanks

  • 5
    Great upgrade

    Posted by Peter Vernaglia on 5th Aug 2022

    The Blast Pack is a great upgrade for the Mark IV, I can really feel where the trigger is going to break now. So happy I did it.

  • 5
    Great upgrade

    Posted by AndyC on 14th Apr 2022

    Excellent upgrade. The steps were easy to follow on the Youtube video - but at first I thought I'd done something wrong as, once I'd finished, I couldn't cock the hammer. Stupid me - it turns out that the hammer takes a LOT of pressure to cock back (even on the little Ruger .22 pistol), so I hadn't done anything wrong - and the trigger is amazing! Well worth every cent and then some - thank you, guys.

  • 5
    Blast Pack

    Posted by Rob on 13th Feb 2022

    I love it. It’s easy to install with the aid of the install video (I am not the most mechanical guy). The trigger is now much lighter, consistent, and breaks cleanly. There is no more of the Ruger gritty feel. The parts are made of quality material and finished smooth. I have now ordered the Cornerstone extended safety, the Titan extended mag release, and the extended bolt stop.

  • 5
    Blast Pack

    Posted by Dan on 27th Jun 2021

    Purchased Blast Pack for my Ruger MKIV 22/45 Lite. I had already installed the Victory Trigger but still wanted a better trigger. Watched the video, fairly easy and straight forward installation. Trigger pull improved, down to 2# as per my Lyman digital tigger pull gauge. Beside the improved trigger pull it removed the mag disconnect which I really disliked. Over all great purchase and very satisfied.

  • 5
    Trigger System

    Posted by Doug H on 14th Jun 2021

    I already had the Victory Trigger on my Mark IV and decided the use this kit to further upgrade the trigger. I have other Mark IV pistols but I used Apex parts in those. The Tandemkross kit was fairly easy to install. In conjunction with the Victory Trigger, the kit produced a dramatically lighter trigger pull. I still like the Apex kit but this kit definitely produces a lighter pull. I am very pleased with it.