January 4th, 2016

Updated Hodgdon and IMR Relative Burn Rate Chart

Hey guys, you’ll probably want to download this new Powder Burn Rate Chart issued by Hodgdon/IMR. This new table shows the latest IMR powders including the Enduron series (IMR 4166, 4451, 4955, 7977), shown in green below. This chart provides useful information for all hand-loaders. When doing load development, and testing one powder versus another, it’s generally wise to choose propellants that share the same relative burn rate, as least for starters. NOTE: Hodgdon powders are shown in blue, while IMR standard powders are shown in yellow. DOWNLOAD Chart HERE.


NEW POWDER BURN RATE TABLE from IMRPowder.com

Hodgdon IMR Winchester Burn Rate Powder speed table relative table chart

CLICK HERE to Download Chart as PDF File.

Story find by EdLongrange. We welcome reader submissions.
Permalink Bullets, Brass, Ammo, Reloading 4 Comments »
July 5th, 2012

Angle Cosine Indicator (ADI) Aids Hunters

Unlike benchrest shooters, hunters need to be able to make shots with significant up-angles or down-angles. That whitetail buck may be poised on a ridgetop above you, or in a valley below. When making an angled shot, the hunter faces a complex ballistic solution. This is because the angle of the shot alters the effective ballistic distance to the target. Whether you shoot up-angle or down-angle, you must adjust your elevation “clicks” as if you are shooting a shorter distance. See the diagram below. The drop of your bullet is a function of gravity, which remains constant. When you shoot at a steep angle, the actual bullet travel over the ground will be less than the sloped distance to your target.

But how do you determine the flat-line or “gravity-corrected distance”? There’s a simple tool that will do the job: the patented Angle Cosine Indicator (ACIĀ®) invented by U.S. Army Veteran Ward Brien.

When you aim your rifle at an angle, the ACI shows the cosine value of your intended shot by means of a highly visible index mark. You simply multiply the true, sloped distance to your target by the cosine value (as a percentage), to get the corrected, flat line distance to target, i.e. the bottom leg of the triangle. Then set your scope’s elevation accordingly. For example, if you range the line of sight distance to your target at 400 yards, and the ACI shows a cosine value of 0.87 (for 30 degrees), then your flat-line “gravity-corrected distance” is 400 x 0.87 = 348 yards. Now Dial your elevation for 350 yards (from your come-up table).

This simple multiplication method works well for typical 100-300 yard hunting distances, but it’s not perfect. For longer-range shots, out to 1000 yards, some other factors come into play. The most accurate method for long ranges is to input the cosine number into ballistic software, such as Exbal Ballistic Targeting Software, that runs on a PDA or smart phone. The software takes into account the fact that, during an angled shot, the bullet must still travel the full distance to target, and will have a longer time of flight than when covering the flat line distance. At very long ranges there can be as much as eight (8) MOA difference between the simple multiplication method and the solution generated by the ballistic software. NOTE: ACI Inventor Ward Brien has posted a Comment to this article which explains in greater detail why inputting the ACI value into a ballistics program is the “preferred method”.

Angle Cosine Indicator ACI

The Angle Cosine Indicator costs $145.95 from Sniper Tools. The ACI is made from aircraft grade aluminum, anodized flat black. Angles are laser-engraved onto the body in five (5) degree increments. The lens is water-resistant, shatter-proof, and shock-proof. Completely mechanical, there are no batteries or electronics to fail. For more info, visit SniperTools.com, or call (818) 359-0512.

Angle Cosine Indicator ACISniperTools.com also offers an Angle Degree Indicator (ADI) for $114.95 (Civilian model). This shows the actual angle from horizontal. If you have a mobile ballistics solver, you can simply input the angle and the ranged yardage and the solver will provide the flatline “gravity-corrected Distance”. Some shooters find it easier to think in terms of the actual angle deflection from horizontal.

There are several ways to mount an ADI or ACI. We prefer a 90° slotted mount attached to a Picatinny rail. SniperTools.com sells a Badger Ordnance ACI/ADI Rail Mount for $60.00.

Permalink News, Optics 6 Comments »
December 12th, 2010

Hodgdon Equivalents for ADI Product Codes

Many of the most popular powders sold under the Hodgdon brand in the USA (including Varget and H4350) are actually made by Thales Australia Ltd. (formerly ADI, Ltd.) in Australia. Some load manuals list Thales (ADI) data, but not Hodgdon data, or vice-versa, so we’ve compiled this list of equivalent powders. If you can’t find a recommended load for a particular Hodgdon powder in your caliber, download the latest ADI Smokeless Powders Handloaders Guide (2010, 5th Edition), a 5-megabyte Acrobat file.

Here’s a list of ADI to Hodgdon Powder equivalents:

AS30N=Clays
AP50N = (No Hodgdon)
AS50N = International
AP70N = Universal
AP100 = (No Hodgdon)
AR2205 = H4227
AR2207 = H4198
AR2219 = H322
Bench Mark1 = (No Hodgdon)
Bench Mark2 = BenchMark
AR2206 = (No Hodgdon)
AR2206H = H4895
AR2208 = Varget
AR2209 = H4350
AR2213 = (Discontinued)
AR2213SC = H4831
AR2217 = H1000
AR2225 = Retumbo
AR2218 = H50BMG

ADI smokeless power Hodgdon

About IMR 8208 XBR
NOTE: Although new IMR 8208 XBR is made by Thales (ADI), Hodgdon has not published an ADI-equivalent product code. Thales has loaded some of the 8208 XBR into military ammo. However, Thales Australia Ltd. tells us: “[We] have yet to release the IMR 8208 XBR propellant in Australia to the sporting shooters market; thus it does not have an equivalent Thales (ADI) name”.

Permalink Reloading 7 Comments »