Mk 262 Cloning - pt 4 - Fine tuning AA2520 and CFE 223 loads

Published on September 8, 2017
Duration: 32:46

This video fine-tunes Mk 262 clone loads using Accurate 2520 and CFE 223 powders to match Black Hills 77gr OTM factory ammunition. Accurate 2520 at 25.2 grains with a Sierra 77gr SMK bullet achieved 2768 fps and a 0.416" group, while a Nosler 77gr CC at 25.0 grains yielded 2730 fps and a 0.371" group. CFE 223 showed lot-to-lot variation and degraded accuracy at higher pressures.

Quick Summary

Accurate 2520 at 25.2 grains with a Sierra 77gr SMK bullet achieved 2768 fps and a 0.416" group for the Mk 262 clone. A Nosler 77gr CC at 25.0 grains yielded 2730 fps and a 0.371" group. CFE 223 matched velocity but degraded accuracy.

Chapters

  1. 00:00Introduction & Project Goals
  2. 01:19Factory Ammo Runout Testing
  3. 05:33Load Data Review & Planning
  4. 07:59Component Selection & Prep
  5. 09:23Range Testing: Accurate 2520
  6. 12:39Range Testing: CFE 223 & Runout Results
  7. 15:08Final Analysis & Future Steps

Frequently Asked Questions

What powders are being tested for the Mk 262 clone load?

The video focuses on fine-tuning loads using Accurate 2520 and Hodgdon CFE 223 powders. The goal is to match the performance of Black Hills 77gr OTM factory ammunition, specifically targeting velocities between 2750 and 2760 fps.

What were the results of the Accurate 2520 load testing for the Mk 262 clone?

Accurate 2520 at 25.2 grains with a Sierra 77gr MatchKing bullet achieved 2768 fps and a 0.416" group. A Nosler 77gr Custom Competition bullet at 25.0 grains yielded 2730 fps and a 0.371" group.

How did CFE 223 perform in the Mk 262 clone load development?

CFE 223 at 25.4 grains matched the target factory velocity of 2768 fps, but accuracy degraded. This suggests potential lot-to-lot variation or pressure issues with CFE 223 in this application.

What components are used for the Mk 262 clone ammunition?

The clone loads use Sierra 77gr MatchKing or Nosler 77gr Custom Competition bullets, Lake City brass, CCI No. 41 primers, and maintain an Overall Length (OAL) of 2.246 inches.

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