Speer LE 64 Grain Gold Dot

By: MOLON

Speer has expanded its line of Gold Dot ammunition to include rifle ammunition in 223 Remington. The ammunition examined for this post is loaded with a 64 grain bonded soft point bullet that has less exposed lead at the meplat than Federal’s 62 grain Trophy Bonded Bear Claw bullet that is used in their LE223T2 load.

The 64 grain Gold Dot bullet has a boat-tail and a cannelure. This load is charged with a ball powder that according to Speer is a “flash suppressed propellant.” The primers are sealed and crimped in place, however, there is no sealant at the case mouth.

 

The 64 grain Gold Dot bullet has a nominal length of 0.825” and a specific gravity of 10.0. A barrel with a 1:9” twist should stabilize it quite well.

From ATK’s website:

“Like their handgun counterparts, the Gold Dot rifle bullets are constructed using Gold Dot technology. The process of joining the jacket and core one molecule at a time eliminates the potential for the leading cause of bullet failure—jacket/core separation. It also ensures impressive weight retention through barriers as tough as auto-glass.”

The 64 grain Gold Dot load was chronographed from a 20” Colt M16A2 barrel, a 16” Colt light-weight barrel and a 14.5” Colt M4A1 barrel. All of the barrels have chrome lining, NATO chambers and 1:7” twists. 10-shot strings of the load were fired over an Oehler 35-P chronograph with “proof screen” technology. All velocities listed are muzzle velocities as calculated from the instrumental velocities using Oehler’s Ballistic Explorer software program.

Accuracy testing was conducted following my usual protocol of firing 10-shot groups from a concrete bench at a distance of 100 yards using my 24” Krieger barreled AR-15. This barrel has a 1:7.7” twist. The free-float rail of the rifle rested in a Sinclair Windage Benchrest and the PRS stock was stabilized in a Protektor bunny-ear rear bag. Wind conditions were monitored using a Wind Probe. Sighting was performed using a Leupold Competition Series scope with a mirage shade. The scope was adjusted to be parallax free at 100 yards.

Prior to testing the 64 grain Gold Dot load, I fired a 10-shot control group using hand-loaded 69 grain Sierra MatchKings. That group had an extreme spread of 0.86”. Three 10-shot groups of the Speer LE 64 grain Gold Dots fired in a row had extreme spreads that measured:

for a 10-shot average extreme spread of 1.12”! I over-layed those three groups on each other using RSI Shooting Lab to form a 30-shot composite group. The composite group had a mean radius of 0.33”.

For comparison, previous testing of the Black Hills blue box 75 grain MHP load fired from the same set-up as above produced three 10-shot groups at 100 yards that had an average extreme spread of 1.14” and a mean radius of 0.37” for the 30-shot composite group.

Velocity Update for the 64 grain Gold Dot

Manufacturers typically use bolt-action “test barrels” to obtain their advertised velocities for their ammunition. These test barrels are usually 24” long and often have minimum spec SAAMI chambers. These factors combine to give ammunition higher advertised velocities than the velocities that we actually obtain from our AR-15s. Also, due to its gas operating system, the AR-15 looses 20 fps or more of velocity compared to an equivalent barrel without a gas system.

Sierra test barrels

Shooting Times 2009

As an example, Hornady advertises the velocity of their 55 grain TAP load as 3240 fps. When fired from an AR-15 with a 24” Krieger barrel with a 5.56 Match Chamber (and of course a gas operating system) the muzzle velocity of the 55 grain TAP load was 3167 fps, for a difference of 73 fps from the advertised velocity.

Speer’s website reports the muzzle velocity of the 64 grain Gold Dot load as 3000 fps. When fired from my 24” Krieger barreled AR-15, the 64 grain Gold Dot load had a muzzle velocity of 2912 fps, for a difference of 88 fps from the advertised velocity.

Terminal Ballistic Properties of the 64 grain Gold Dot

Thanks to the efforts of Dr. G.K. Roberts, we now have some excellent answers to the questions of terminal ballistics pertaining to the Speer 64 grain Gold Dot LE load. The results shown below indicate the penetration of this load in bare ballistic gelatin as well as after having passed through auto-glass. Auto (safety) glass is one of the most difficult barriers (of those commonly tested) for 5.56mm/.223 Remington loads to penetrate and still perform adequately in ballistic gelatin.

Comparisons.