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Reference

These posts include reference materials I’ve created and find myself using frequently, as well as free downloads.

MIL vs MOA: An Objective Comparison

There are a lot of articles and forum threads out there comparing MIL and MOA, but most either aren’t objective or they’re overly complex. I’ll try to avoid both of those pitfalls in this article. Executive Summary A few months ago I asked Bryan Litz whether he personally used MIL or MOA. Bryan is an expert among experts in the shooting community, and after reading his books I’ve gained a respect for his scientific approach to decisions like this. His response was so concise and objective, I thought it could serve as the executive summary for this whole comparison: “You ...

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Rifle Screw Torque Settings Guidelines

I’ve had to reference back to these torque specifications a couple times, and thought it’d be helpful to post. It is a list of the recommended screw torque settings for most rifle parts, like action screw torque. These come from a lot of different sources (including manufacturers on the phone), but one great one is Brownell’s “Torque Specifications for Gunsmiths” Article.  As that article explains, these specs are subject to change as companies change their manufacturing processes, materials, and design.  However, many people believe consistent torque is at least as important as the actual number of inch/pounds (especially when talking about action screws).  Here is an excerpt from that article that ...

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Oehler 35P Chronograph Manual

Oehler Research definitely makes the best chronographs in the industry … hands down, no argument.  I had a chance to talk with Ken Oehler at the 2013 SHOT Show, and have to say it was one of the most enjoyable conversations I’ve ever had with someone regarding ballistics.  Ken knows his stuff, and is an expert among experts in shooting sports.  I’ve used an Oehler 35P, which is the pro-sumer grade model they offer (i.e. model targeted at professionals or high-end consumers) and can say they are a joy to use … and VERY accurate.  You get very few errors and ...

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Detachable Magazine Dimensions & Max COAL

The table below contains the maximum Cartridge Overall Length (COAL) for popular detachable magazines for rifles.  This is important to consider when picking a rifle cartridge to ensure you have enough clearance to “chase the lands”, which just means as your chamber throat begins to naturally erode from use you seat your bullet further and further out so that it maintains the same relative position with the rifle lands.  Many people start with their COAL almost maxed out in their magazine, and as their chamber throat starts to wear they are forced to choose between loss of accuracy from not ...

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Portable Reloading Press Plans

I wanted to create a portable reloading press stand that I could mount my full-size RCBS Rockchucker Press or smaller RCBS Partner Press to.  The plans I came up with were simple to build, used easy to find materials, and the finished product has worked exactly like I was hoping.  The stand is very strong and stiff, which is critical when designing a reloading press mount.  It is ergonomic and natural to use on either a table top or a work bench surface.  I just use one or two Irwin Quick-Grip Clamps to hold it securely to the surface.  The stand has “window cutouts” ...

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7mm Rem Mag Chamber Print

When the 7mm Remington Magnum was originally released, it was met with overwhelming demand.  Every rifle manufacturer rushed to offer rifles chambered for the new cartridge, and in the rush some of the chamber dimensions varied slightly from different manufacturers.  This variation in the 7mm Rem Mag chamber dimensions has carried on to today, and there is still more differences in the chamber dimensions than for virtually any other rifle cartridge. What’s a chamber print? A “chamber print” is an illustration of the chamber reamer used to cut a rifle’s chamber.  It contains all of the key dimensions related to ...

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Standard Atmospheric Pressure for Long Range Shooting

I’ve found myself needing to reference this info a lot while making data cards. It indicates the standard atmospheric pressure at different elevations. Pressure can vary quite a bit from the “standard” listed here, and although that won’t make much of a difference at short or mid ranges … when you get out to 1,000 yards or beyond it can make a noticeable difference. If you know the specific pressure the day you are shooting, it could really help your ballistics tables be more accurate. Having a Kestrel that can measure the instantaneous pressure is the best solution. Altitude (ft) ...

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RCBS Rock Chucker Reloading Press Mounting Template & Dimensions

I have needed the exact dimensions of both the RCBS Rock Chucker Supreme Press and RCBS Partner Press a few times, as I was working on custom ways to mount them (like this portable reloading press stand).  Unfortunately, RCBS doesn’t publish anything to help with that … so I made a template and thought I would share it in case it helps anyone else. Download RCBS Press Mounting Template with Dimensions  The mounting template, contains the exact dimensions related to the mounting surface, but here are a few more dimensions for presses that are also helpful (and not published anywhere). RCBS Rock Chucker ...

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