November 18th, 2016

Advanced Reloading — Checking the Geometry of Neck Bushings

bushing neck die run-out concentricity

Do you use bushings to size your case-necks? Are you assuming that your bushings are actually round on the inside, with a hole that’s centered-up properly? Well you may be in for an unpleasant surprise, based on what our friend Jim de Kort recently discovered. Jim was concerned about the run-out on his brass. His cases went into his bushing-equipped FL die pretty straight, but came out of the die with up to .004″ run-out. “What gives?”, Jim wondered. “Could the problem be the bushings themselves?”

To answer that question, Jim decided to examine his bushings. Using an Accuracy One Wheel-drive concentricity gauge, Jim checked out some of his neck bushings. What he discovered may surprise you…


Neck Bushing Flaws Revealed

Trust no one… — Jim de Kort

Jim writes: “I measured the concentricity of my 6BR rounds today. I noticed they went into the neck-bushing equipped full-length sizing die with less than .001″ deviation but came out with .003-.004″. The culprit, it appears, was the bushing itself. Without it the cases stayed within .0005″ to .001″ deviation, so something was happening with the bushing.

One bushing had .00025″ deviation on the outside, yet almost .003″ on the inside, so it is crooked. But even when using a bushing that is within .001″ I still get .003″ runout after sizing. I repeated the same procedure for my 6×47 and got the same results. When using the bushing, concentricity suffers a lot.”

Before we bash the bushing-makers, we must acknowledge that many different things can contribute to excessive run-out and/or mis-alignment of case-necks. We don’t have all the answers here, and Jim would be the first to say that some mysteries remain. Still, these are interesting results that give all precision hand-loaders something to think about.

Jim Borden of Borden Accuracy also offers this tip: “Check the trueness of the face of the die cap. That has more to do with trueness than the bushing. Also check perpendicularity of hole in bushing to top surface. When I was making dies, the cap was made by threading and facing the threaded tenon in same setup.”


Editor’s Comment: Many people have great results with neck-bushing dies, but Jim isn’t the only fellow who has seen some very odd results. I personally employ honed, non-bushing dies for many of my chamberings. These non-bushing dies (with the necks honed for .002-.003″ neck tension) produce extremely straight ammo, with run-out consistently under .0015″.

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September 25th, 2014

Most Popular AccurateShooter Facebook Post Ever

Here’s a humorous illustration that pokes fun at golf. We posted this on Facebook recently. To our surprise this generated 356 shares, and reached 22,000+ readers, making this the most popular AccurateShooter Facebook post ever. “Golf — the willful misuse of a perfectly good rifle range.”

Golf shooting range

So, what do you think — should golf courses be converted to shooting ranges? Is golf truly a “good [shoot] spoiled”? This photo was shared by our shooting buddy Jim de Kort from Holland.

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Here are some comments from our Facebook fans:

“Actually golf and shooting are similar sports. Trying to shoot a small object into a small hole from long range.” — Eric A.

“You can hit a golf ball 300 yards, but I can hit a golf ball AT 1000 yards.” — Zach S.

“The game should be changed. You should hit the ball out as far as possible, then get your rifle out and hit the golf ball. The most golf balls hits… with the rifle wins!” — Hui H.

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