Category: AR-MPR Phase II

AR-MPR: Accurizing the Upper Receiver – Test Results

In the following posts: AR-MPR: Accurizing the Upper Receiver – Part II: Milling and Receiver Face Truing AR-MPR: Accurizing the Upper Receiver – Part I: Prep and Welding AR-MPR: Accurizing the Upper Receiver – Overview I’ve documented an experiment in accurizing the upper receiver of the AR-MPR rifle. It was a bit painful to file […]

AR-MPR: Accurizing the Upper Receiver – Part II: Milling and Receiver Face Truing

In this post, I’ll finish covering the accurizing steps and experiments for the AR-MPR upper receiver- so far, we’ve covered the following: AR-MPR: Accurizing the Upper Receiver – Overview AR-MPR: Accurizing the Upper Receiver – Part I: Prep and Welding Following the welding process, I carefully milled and measured the sides of the upper receiver […]

AR-MPR: Accurizing the Upper Receiver – Part I: Prep and Welding

In my last post, outlined some ideas and goals for talking the slop out of the fit between the upper and lower receivers on the AR-MPR rifle. The first step is to remove the gaps between the sides of the upper receiver lugs, and the channels at the front and back of the lower receiver. […]

AR-MPR: Accurizing the Upper Receiver – Overview

A while back, I posted some AR-MPR rifle accurizing plans. This was my first-pass at enhancing the accuracy of the AR-MPR rifle. Since this post, I have had a few range visits (sorry, don’t have photos as the range does not permit photography) where I did not see the kind of accuracy and consistency that […]

AR-MPR Phase II – Checking and Correcting Bullet Concentricity

If you are a precision shooter, you care about consistency for the cartridges that you shoot. One of the most important factors to measure and control when reloading match ammunition is bullet concentricity. Simply stated, this is the alignment of the case and bullet. If you have “good concentricity”, you will have the axis of […]

AR-MPR Phase II – Seating Bullets

In this video, we’ll use the Hornady OAL Gage measurements from our first Phase II loading video: AR-MPR: Phase II – Determining Max COL with OAL Gage and measure the dimensions of the cartridge and magazine to determine the optimal bullet seating depth for the bullet and rifle in question. We’ll then use the Redding […]

AR-MPR: Phase II – Magpul PRS Stock and XTM Rail Panels Install

One of the important aspects of a precision rifle is the overall rigidity of the entire rifle – the action, barrel, stock, and other components – the entire unit must be solid in order to shoot with maximum precision. The AR-MPR rifle was initially put together with an M4-Style 6 position collapsible stock. This imposed […]

AR-MPR: Phase II – Charging Cases with the Redding 3-BR and Hornady Auto Charge

In this video we’ll continue the precision loading process by using the Redding 3-BR powder measure and the Hornady Auto Charge to dispense powder loads. Next, we’ll cover calculating optimal seating depth, and seating the bullets. Thanks, Gavin http://ultimatereloader.com/wp-content/uploads/2010/11/AR-MPR-logo-wide-small.jpg

AR-MPR: Phase II – Rifle Accurizing Plans

I just read a great article written by Robert Whitley of www.6mmar.com fame that was posted on the http://accurateshooter.com blog: What Makes an AR Accurate — Whitley Offers Answers Talk about good timing! This post helped me plan the first wave of accurizing activities for the AR-MPR rifle. My goal is to remove any factors […]

AR-MPR: Phase II – Sizing Depriming Priming .223 Remington

In this video we’ll start the precision loading process by lubing, sizing, depriming, and priming cases. We’ll walk through the features of the Redding Big Boss II, show how to lube .223 cases, validate sizing die setup, and then size/deprime/prime the cases. Next, we’ll cover charging the cases with the Redding 3-BR benchrest powder measure […]

AR-MPR: Phase II – Determining Max COL with OAL Gage

One of the important things to know before loading rifle ammunition is how far out (shallow) you can seat bullets, and what the optimized seating depth is for a particular bullet for your rifle and shooting application. For AR-MPR Phase II, we’re going for maximum accuracy, and also need to assure proper feed characteristics so […]

AR-MPR: Phase II Hornady Equipment Overview

In my last post, I gave an overview of some of the Redding equipment that we’ll be showcasing during Phase II of the AR-MPR project. I this post, I’ll cover some Hornady equipment that will also be used for this precision loading phase of the AR-MPR project. We’ll cover more Hornady gear (such as the […]

AR-MPR: Phase II Redding Equipment Overview

For Phase II of the AR-MPR we will be focused on precision handloading techniques and load development. For this phase of the project, I decided to showcase some of the popular Redding Reloading products that have an outstanding quality reputation. Here, we’ll talk briefly about each of these products. The Big Boss At the heart […]

AR-MPR: Phase II Kick-Off

Now that we’ve build and function checked the AR-MPR rifle (See Brownells Videos for Complete Details), it’s time to move from Phase I (Build) to Phase II – Precision Loading and Rifle Accurizing/Tuning. This rifle has already proven that it’s capable of meeting the original accuracy goal of .5 – .75 MOA (See Range Report […]