SPR Build: FMJ 5.56 out to 700 yards

Published on March 22, 2022
Duration: 20:23

This guide details the construction of an 18-inch Special Purpose Rifle (SPR) chambered in 5.56 NATO, designed for consistent accuracy out to 700 yards. It emphasizes component selection for weight, performance, and versatility in varied shooting conditions, drawing on the practical experience of the instructor.

Quick Summary

An 18-inch SPR build in 5.56 NATO, featuring components like a Geissele SSA-E trigger and Nightforce 2.5-10x optic, is designed for consistent accuracy up to 700 yards. It balances weight and performance, achieving sub-MOA with match ammo, and utilizes a pencil barrel profile for manageability.

Chapters

  1. 00:00Introduction to the 18-inch SPR Build
  2. 01:10Sling Choice: V-TAC
  3. 01:53Defining the SPR Philosophy
  4. 03:37Stock and Receiver Group
  5. 04:45Two-Stage Trigger Benefits
  6. 06:01Grip and Magazine Selection
  7. 06:36Optics: Nightforce 2.5-10x vs. LPVO
  8. 11:19Magnification Sweet Spot
  9. 12:16Top-Mounted Red Dot
  10. 13:01Rail and Barrel Specs
  11. 14:41Accuracy and Ammo Performance
  12. 16:37Bipod and Accessories

Frequently Asked Questions

What is the optimal barrel length and profile for a 5.56 SPR build focused on long-range accuracy?

An 18-inch barrel with a pencil profile is recommended for an SPR build. This length balances sufficient velocity for extended ranges with a manageable weight, keeping the overall rifle around 10 lbs unloaded, which is ideal for maneuverability and sustained use.

Why is a two-stage trigger preferred for a Special Purpose Rifle (SPR)?

A two-stage trigger, like the Geissele SSA-E, offers enhanced versatility for an SPR. It provides a heavier initial pull for safety and control during movement or close engagements, followed by a lighter, crisper break for precision shooting at longer distances.

What optic magnification range is ideal for an SPR build designed for 700-yard engagements?

A 2.5-10x magnification range is considered optimal for an SPR. This provides enough magnification for accurate shots at extended ranges while retaining a usable field of view at lower powers, functioning effectively as a 'fighting rifle' optic.

How accurate can a custom 18-inch SPR build be with different types of ammunition?

A well-built 18-inch SPR can achieve approximately 1.5 MOA with standard ball ammunition. With match-grade ammunition, accuracy can improve to sub-MOA, which is sufficient for consistent hits on targets out to 800 yards.

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