Observations on the Accuracy of a 20” Lothar Walther AR-15 Barrel
Observations on the Accuracy of a 20” Lothar Walther AR-15 Barrel
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I’ve used a 20” stainless-steel Lothar Walther barrel for evaluating the accuracy (technically precision) of several different 5.56mm/223 Remington factory loads now. Prior to firing each of these factory loads, I’ve fired a 10-shot control group using some of my “generic” hand-loads; by generic, I mean that these hand-loads were not “tuned” for this specific barrel. The targets that will be shown below are a collection of some of these 10-shot control groups.
I purchased this 20” Lothar Walther barrel directly from Lothar Walther. The barrel is manufactured from LW50 stainless steel. The Lothar Walther website states that LW50 was developed “in 1994-95 as a safe alternative to 416R and to solve durability problems associated with 416R.”
Lothar Walther barrels are produced using button rifling. This barrel has traditional rifling (not polygonal rifling) and has a 1:8” twist rate. The barrel has a 223 Wylde chamber, “M4” feed-ramps and a recessed target crown.
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I installed this Lothar Walther barrel in a LaRue Tactical Stealth upper receiver with “M4” feed-ramps.
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The barrel was free-floated with a LaRue Tactical 12” railed handguard.
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All shooting was conducted from a concrete bench-rest from a distance of 100 yards (confirmed with a laser rangefinder.) The free-float handguard of the rifle rested in a Sinclair Windage Benchrest, while the stock of the rifle rested in a Protektor bunny-ear rear bag.
Sighting was accomplished via a Leupold VARI-X III set at 25X magnification and adjusted to be parallax-free at 100 yards. A mirage shield was attached to the objective-bell of the scope. Wind conditions on the shooting range were continuously monitored using a Wind Probe. The set-up was very similar to that pictured below.
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Finally, the 10-shot control groups . . .
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Lastly, for any Internet Commandos in our viewing audience, here's a pic of a 3-shot group fired from the Lothar Walther barrel. The group has an extreme spread of 0.183".http://www.ar15.com/images/smilies/icon_smile_big.gif
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