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Reviews & Ratings for TANDEMKROSS Tandemized Ruger Mark IV and Mark IV 22/45 Cthulhu Lower — 11 reviews

(11 reviews)
TANDEMKROSS Tandemized Ruger Mark IV and Mark IV 22/45 Cthulhu Lower
TANDEMKROSS Tandemized Ruger Mark IV and Mark IV 22/45 Cthulhu Lower
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Most Helpful Positive Review Ruger 22/45 Lower in Aluminum is the way to go
Built my own 22/45 using this lower and a Volquartsen upper. The TandemKross Cthulhu lower is simply incredible. Firstly, it's machined aluminum, not polymer, so tolerances and fitment are far superior and it feels great in the hand. Comes fully assembled with ALL of the TandemKross bits and pieces to make it great. Victory trigger, extended mag release, larger slide stop/release, thumbrest safety and a thumbrest for your offhand too, made by Strickland, plus TandemKross's hive grip, which feels great. Also worth noting is the slide stop pin that sticks up in the back is fully aluminum and no...
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22/45 race gun lower

by ELEMENT 3 GUNWERKS, Verified Owner from AZ, United States Written on January 3, 2026
Best pound for pound knock out when it comes to anything with the 22/45 this paired with the volquartsen mamba barrel is a same hole race gun on the market tandem Kross didn’t this all the way right
Pros:
  • None
Cons:
  • NONE !
Would recommend: Yes
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Custom Build Bonus

by Aaron., Verified Owner from OH, United States Written on June 1, 2025
I bought this for a custom mk4 build and like the other tandemkross items I have bought before this did not disappoint. Fit and finish are excellent and it has all of the improved parts installed with no assembly required. Fit up to a Tac Sol upper is flawless and all around could not be happier. The price is high but if you were to piece out each part this frame does save you some money.

Word of warning, this frame does not have the quick detach takedown button and instead ops for an allen head set screw to secure the upper and lower.
Pros:
  • Fit & finish
  • Conformable
  • Build / Quility
Cons:
  • Price (a little steep!)
Best Used for:
  • Target & Competition Shooting
Would recommend: Yes
Was it helpful to you? Yes | No
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Tandemkross 22/45 complete lower.

by Rick, from TX, United States Written on May 24, 2025
Beautifully machined. Works great. Fits like a glove and operates flawlessly.
Pros:
  • quality machined part
Cons:
  • None
Would recommend: Yes
Was it helpful to you? Yes | No
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Tandemkross 22/45 complete lower

by Rick, from TX, United States Written on May 17, 2025
Excellent. Crisp trigger. Nicely finished. Very pressed with my purchase.
Would recommend: Yes
Was it helpful to you? Yes | No
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Best mark iv lower

by Jm, Verified Owner from WA, United States Written on December 8, 2024
Super comfortable. Grip and thumb ledges are awesome. Trigger is crisp and light. Everything you would want to do to a mark iv.
Would recommend: Yes
1 of 1 found the following review helpful.
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All the bells and whistles

by Tony, Verified Owner from AR, United States Written on November 27, 2024
Take your .22 to a whole new level! Awesome design, feel, and function. Great customization options.
Pros:
  • all of them
Cons:
  • None
Would recommend: Yes
Was it helpful to you? Yes | No
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Tandemkross Cthulhu

by Ben, Verified Owner from NC, United States Written on November 27, 2024
The fit and finish is great on the lower. Locks up tight with my upper and the trigger feels great.
Would recommend: Yes
Was it helpful to you? Yes | No
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Ruger mark iv

by MK3and4, Verified Owner from NC, United States Written on November 18, 2024
This is a fantastic product. built right out of the box…just add your favorite barrel (volquartsen) And you’re done. FYI, You do lose the quick takedown button. You use a Allen key with locking screw instead to engage the hook . to me, I don’t care if it takes a little longer to field strip . I’m used to the mark 3 anyway. It’s about the same amount of time to takedown. think i like the volquartsen trigger (hammer and sear) better. but i’ll give it some time to break in first.
Pros:
  • Built
Cons:
  • no quick release
Best Used for:
  • Mark IV
Would recommend: Yes
1 of 1 found the following review helpful.
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Tandemkross Cthulhu lower for Ruger mk4 lower

by Camp, Verified Owner from AR, United States Written on October 1, 2024
Fit and finish is awesome. Fits upper with no wiggle or gaps.
Pros:
  • None
Cons:
  • Price but definitely worth it
Would recommend: Yes
Was it helpful to you? Yes | No
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Love the trigger on this

by PAnewbie, Verified Owner from PA, United States Written on September 17, 2024
This upgraded base is amazing, and would highly recommend it
Would recommend: Yes
Was it helpful to you? Yes | No
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