Letters: Bullet Speed Clarification

I was pleased to read the sidebar “Bullets Make The Difference” in the April article “Tweaking the AR15 for High Power Use.” To learn that the 80-grain .224 bullets can be driven 300 fps faster than Lake city Match M852 was most gratifying, especially since the data developed by Sierra Bullets shows max velocity at only 2600 fps out of a AR15 with a 20-inch barrel.

The American Rifleman has published the velocity of M852 to be 2600 fps out of the M14 with a 22-inch barrel. This suggests an attainable velocity for the 80-grain .224 VLD bullets of about 2900 fps out of an AR-15. This is really great news. I would appreciate your sharing your loading edata with your readers or at least advising the orginal source of this data so we can all enjoy the benefits thereof. If you have pressure data too, it would be most helpful.

-Robert T. Daniel
Center, TX

Mr. Zediker responds: The reference in the article was specifically made for JLK bullets. By the way, the Sierra 80 grain is not a VLD, and that’s why Sierra doesn’t call it one. Bill Davis designed the VLD, and it has characteriestics which uniquely qualify it for the VLD designation.

Sierra is correct in giving 2600 fps as a ceiling for its 80-grain MatchKing. Due to differences in design and bearing surfaces, the Sierra will not come close to the maximum velocity attained by a JLK or Berger. It is not recommended to use JLK data for Sierra 80-grain MatchKings. Don’t even reduce a load listed for a JLK and try it with Sierra 80 grain; use Sierra supplied data and your own common sense by starting out a least one full grain under what Sierra lists as a maximum. Given the right powder, case, and primer combination, it is possible to attain 2850 fps from a JLK, which is 300 fps faster than what is printed for M852.

Please keep in mind there are a myriad of things that can influence pressure and velocity on any given day, and with any component combination. It’s foolhardy to start at a maximum listed loading. Tip: to get the best accuracy from the Sierra 80 grain, shoot a stick powder and run it a little slower than the 2600 fps maximum.

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Better Benchrest Technique
I want to get better accuracy out of a used Anschutz free rifle I bought, which means lot-testing ammo. But to remove any bias I might introduce by shooting the gun in prone, I want to shoot off a rest and bench. Do I need to spend $500 for a Ransom Rest to get good accuracy?

-Tom Ball
Greenville, SC

Very few shooters know how to shoot a rifle properly from a bench. There are a few important items you need to consider. If possible, shoot off a concrete bench that has a separate seat or stool on which you can sit. This reduces vibration your body imparts to the bench. A quality front rest, such as the Ransom, allows you to make fine horizontal and vertical adjustments easily. These rests make the job easier, but they’re not absolutely mandatory. You should buy a special benchrest shooting sandbag which contours to the shape of your rifle’s forearm width and shape and a “bunny ear” rear bag. Other helpful items include windmills and/or wind flags. Let the rest and sandbags hold the gun in place when you’re shooting, so you don’t introduce movement during the shot, and strive to return the gun to a consistent initial aiming point between shots. Your hold on the rifle should not vary from shot to shot. Consistency is what you want to achieve.

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Defense Worry
Regarding Judy Woolley’s April “Shooting Big Bores Comfortably” article, my concern is that two of the shooting techniques discussed—bent elbows and thumbs near the slide—may absorb energy necessary to operate the slide. The bent elbows will flex, which will slow the slide down, and the thumbs may contact the slide, which will facilitate misfeeds. This may be deadly if that same gun and position are used in a self-defense situation.

-E. Forrest Bonner
Huntington Beach, CA