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About the Ultradyne UD3 Chassis
There are three different models of the UD Chassis: the UD3, UD5, and UD7.
Our .308 Shorty was born in a Foundation Stock and designed to be compact and versatile. A UD3 chassis just made sense.
From Ultradyne USA:
The Ultradyne Chassis is crafted from a solid bar of 6061 T6 Aircraft Aluminum for exceptional strength and durability. The one-piece design weighs between 1.1 and 1.3 pounds, depending on the model. This makes it suitable for both hunting rifles that weigh as little as 6 pounds and long range target rifles that weigh up to 16 pounds. When paired with the Ultradyne Adjustable Butt Stock, it is lighter than most factory stocks yet has the ability to add up to 5 pounds with optional weights.
The Ultradyne Chassis is packed with features including an adjustable magazine release lever, compatibility with AICS magazines, ability to work with any Mil-Spec butt stock, a built-in Arca rail, M-LOK slots on three sides, and Dynalock technology to ensure a secure fit. The action is held in place with V-channel bedding that can accommodate free-floated barrels up to 1.35 inches in diameter.
- 6061 T6 Aluminum
- Cerakote Finish
- Butt stock Interface: Mil Spec
- Grip Interface: Mil Spec A2
- Magazine Interface: AICS
- 1.35” Max. Barrel Diameter
- 17 oz
- 15.3” Length, 4.2” Arca Length
- 8 M-LOK Slots
What’s in the Box
I received the UD3 backbone with three mounting slots in one box along with action screws, mag release, mag catch assembly, Allen keys, a sticker, and some printed materials. This chassis accepts any AR-style grip and buttstock, making this platform particularly affordable and customizable. It has M-Lok, ARCA, and Dynalock all integrated.
I paired the UD3 with an adjustable AR buttstock I had lying around along with a Hogue grip.
Lastly, I added a Magpul 10-round AICS magazine and MDT GRND-POD.
I paired this with .308 tracer and subsonic loads I loaded on the Dillon RL-550C after automated case prep with the Dillon CP2000 and DA3000. The combination of Berry’s 220 grain plated bullet, Trailboss, and the Backcountry yielded near silence with the subsonic rounds.
This formula is fantastic for a truck gun. One of the great things about the Ultradyne UD3 chassis is its versatility and affordability. You can get parts from Ultradyne or use AR parts you have lying around to combine a familiar platform with the advantages of a chassis.
Get the Gear
Order and customize your UD Chassis from UltradyneUSA.com.
The UD ARCA Dynalock Rail is available separately.
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