Loads for the New Alliant Reloder TS 15.5

Two months ago I mentioned Alliant Reloder TS 15.5 powder in the context of powder burn rates and how this new propellant was developed to fit certain applications between Alliant Reloder 15 and Reloder 16. Since then, I’ve used the new TS 15.5 powder for putting together and testing handloads in several cartridges. Here are the results of that exercise.

Hercules Powder Co. introduced the first three Reloder smokeless propellants in 1965. Designated as Reloder 7, 11, and 21, the ascending numbers indicated successively slower burn rates. Alliant Techsystems later acquired Hercules, and along with other popular Hercules propellants like Bullseye, Unique, Blue Dot, Green Dot, Red Dot, etc., rebranded them as Alliant products. Alliant is now a division of Vista Outdoor Inc.

The original Reloder products were soon discontinued; however, several new and improved propellants, including a reprised Reloder 7, were eventually developed. Today, there’s a baker’s dozen with numerical designations from 7 to 50, indicating faster to slower relative burn rates. The newest offering is Reloder TS 15.5.

Reloder 15 was already well established as an excellent medium burn rate powder for medium rifle cartridges like the .308 Winchester. Reloder 16 became a preferred choice for the popular 6.5 Creedmoor and other cartridges. Reloder TS 15.5 was developed to bridge the gap between Reloder 15 and Reloder 16.

Reloder TS 15.5 is an extruded, double-base powder physically similar to Reloder 16. Its chemical composition includes a small percentage of nitroglycerine for extra energy and also a decoppering agent to minimize barrel fouling. The TS prefix stands for “temperature stable” and denotes that its burn rate is consistent over the typical range of hunting temperatures. That factor and very low extreme spreads (ES) and standard deviations (SD) ensure that when you take the shot at the goat, for example, the only things you have to worry about are the difference in elevation, the wind speed/direction, and achieving a stable shooting stance. (Pun intended!)

I’ve been loading a variety of medium rifle cartridges with the new powder, using a comprehensive list of lab-tested load data. In addition to those shown in the accompanying chart, the list included recipes for the .22-250, .260 Remington, and 7mm Mauser. I’m sure additional, similar medium rifle cartridges will be added to Alliant’s reloading guide soon.

I didn’t pursue extensive load development with any cartridge, and where possible, I used the same bullet and primer listed in the data sheets. I reduced the charge rates modestly from the maximum loads provided. There were no unexpected incidents, and recorded velocities tracked Alliant’s results closely. It’s been a while since I recorded multiple single-digit SDs when evaluating a new propellant.

I dispensed the powder with a Redding BR-30 (double throws) and an RCBS Uniflow powder measure. At first, I weighed at least half of the charges until I became confident that the charges wouldn’t vary more than +/- 0.1 grain. Then I checked every fifth one and carefully inspected every charged case before seating the bullets. I also duplicated the listed cartridge overall length (COL) when I used the specified bullet.

The 6.5 Creedmoor and 6mm Creedmoor accuracy results were the best of those tested. The Speer Gold Dot bullets in the 224 Valkyrie and 6.5 Grendel recorded the lowest SDs, but the 6.5 Creedmoor topped with the Speer Gold Dot bullet was a close second.

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