Terminus Helios

Building, Information

Since switching to an Accuracy International rifle I have developed a serious appreciation for 60 degree bolt lift actions. The actions that come to mind are the Sako TRG and Accuracy International. In the past if you wanted a 60 degree bolt lift you had to commit to a non-Remington 700 footprint platform. When Curtis Custom came out with the Axiom we saw the R700 footprint 60 degree bolt lift receiver gain market share in a significant way. The innovation that lead to this was the roller ball tip cocking piece. Inspired by the Sako M995 action Joel Russo formed Terminus and continued to refine his R700 drop-in footprint 3-lug design.

Terminus Helios with DLC finish and Trigger Tech 2-stage prototype trigger.

When I decided to build a Long Range Hunting rifle I knew I wanted an action that featured a 60 degree bolt lift but building off something like a Browning X-Bolt was not acceptable. The heart of my rifle is the Terminus Helios action with magnum bolt face. The features that set this action apart from other R700 footprint 60 degree bolt lift designs like the Ultimatum U300/Deadline & Curtis Custom are the proprietary threaded trigger pins and corrected bolt diameter (0.725″). The corrected bolt diameter maintains R700 footprint drop-in compatibility and avoids the need to trim the magazine latch for proper feeding with some chassis and AICS bottom metals. Other notable features are the one piece bolt, integral recoil lug and improved cantilever style bolt stop which doesn’t require a relief cut in the stock/chassis. Russo’s roller ball tipped cocking piece allows for a light bolt lift and the DLC coating helps the action run extremely smooth, in addition to offering corrosion protection. The threaded trigger pins made the install of the Trigger Tech 2-stage prototype trigger incredibly easy. I like that they avoided a trigger hanger. The Helios action also features a mini-M16 extractor and is AICS .338 LM CIP & Wyatt’s BDL extend box magazine compatible making it perfect for my 28 Nosler Long Range Hunting build.

Terminus proprietary threaded trigger pins.
Photo Credit: Terminus Actions

While using the Helios action I noticed the bolt has no visual indicator for when it’s cocked. I have grown used to having an indicator on my AIAT & Tikka T3. The lack of this feature is not a deal breaker for me but is worth mentioning. The Helios paired with a Proof Research carbon fiber wrapped barrel and CGS Group suppressor has displayed excellent accuracy using factory Hornady Precision Hunter 28 Nosler 162 grain ELD-X ammunition. After shooting five, three ground groups at 100 yards the average came out to 0.6 MOA. The best 3 round group was 0.3 MOA with a muzzle velocity of 3,044 fps. I also had positive results with Nosler Trophy Grade 175 grain AccuBond LR.

The rifle overall has exceeded my expectations. We did have to inlet the KRG chassis a little so the trigger’s safety selector would move freely, but now that the rifle is complete we are excited to put it to use on Dane’s late season cow elk hunt. We were not going to have enough time to develop a load for the rifle and will need to rely on factory ammunition from Hornady. The attention to detail and refinements of the Terminus Helios helped this build come together efficiently. The fit, finish & feel is excellent. I like the short lead in that makes the bolt want to slam shut. The fluting adds a nice aesthetic touch and the 60 degree lift keeps your hand clear of the scope, especially those of you running magnification switch levers.

I plan to hunt with this rifle for years to come in Nevada and neighboring states. I will continually share my experiences, feedback and images over time. I will also be sharing factory ammunition chronograph information and hand load information in “DMR Owners Club” on Facebook. I am excited to see future developments from Terminus and happy to see the 3-lug segment of the market grow. Please feel free to reach out to us anytime if you have questions by emailing dmillerrifles@gmail.com, or call us at (702) 420-9188 Monday through Friday 7 AM to 3 PM.

DMR Long Range Hunting rifle build specs:

  • Terminus Helios action (DLC treated)
  • Cerakote on external portion of receiver & barrel
  • 22″ Proof Research carbon fiber wrapped barrel
  • 7mm 1-8″ twist Sendero contour
  • Chambered in 28 Nosler (SAAMI)
  • 18x1mm muzzle threads (5/8″x24 tpi is standard)
  • CGS Group Hekate .338 LM suppressor (not included)
  • KRG Bravo chassis Cerakoted in Kuiu Vias (done in-house)
  • Trigger Tech 2-stage prototype trigger (Special is standard)
  • Leather Quick Sling from Competent Citizen (not included)
  • Harris bipod with ADM adapter (not included)
  • 5 round 3.715″ AICS magazine

DMR 22" 28 Nosler Long Range Hunting rifle