June 26th, 2018

Sierra Secrets — How MatchKings Are Made

Sierra Bullets Carroll Pilant MatchKing Bullet SMK Bullet-making Jacket

The Making of MatchKings — How Sierra Produces SMKs
All Sierra bullets begin life as a strip of gilding metal, an alloy consisting of 95% copper and 5% zinc. To meet Sierra’s strict quality requirements, the gilding metal requires three times more dimensional and quality control standards than is considered standard in the copper manufacturing industry.

A blanking press stamps out a uniform disc and forms the cup that will be drawn into the MatchKing jacket. The cup is then polished and sent to a draw press to be drawn into a jacket that is longer than needed for the future MatchKing, thus allowing for the trim process. Press operators constantly check concentricity to make sure we have only quality jackets. The jackets then go to a trimmer where they are visually inspected again.

Sierra Bullets Carroll Pilant MatchKing Bullet SMK Bullet-making Jacket

After being polished a second time, the jacket travels to the bullet press. In the meantime, 80-pound lead billets are being extruded into lead wire for the cores where great care is taken so that the core wire is not stretched. The core wire is lightly oiled before continuing to the bullet press to be swaged.

The lead core wire and trimmed jacket meet at the bullet press where the first stage forms a boattail on the jacket. The lead core is then formed on top of the bullet press and fed down into the jacket. In one stroke of the press, the MatchKing is formed.

Sierra Bullets Carroll Pilant MatchKing Bullet SMK Bullet-making Jacket

Quality control technicians pull samples from each lot of MatchKings to make sure they meet Sierra’s stringent standards. Samples are then sent to Sierra’s 300-meter underground test range (shown below) to be shot for accuracy on mechanical mounts referred to as “unrestricted return to battery rests” that Sierra designed and built in-house.

Sierra Underground Tunnel test facility Sedalia, Missouri

Sierra bullet sale Clarus Corporation

After inspection, the bullets are placed in the familiar green box along with reloading labels. They are then shrink-wrapped and shipped all over the world.

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January 13th, 2017

Perfection at the Core — Bullet Making Tips from BIB Bullets

Randy Robinett, founder of BIB Bullets, is a highly respected custom bullet-maker. In recent years, Randy’s 30-caliber projectiles have won countless benchrest-for-score matches, and captured many National titles. If you want to “run with the big dogs” in score competition, campaigning a 30BR with BIB bullets is a very smart way to go. In this article, Randy talks about the process of creating highly uniform cores for benchrest bullets.

This article originally started as an exchange of posts in Stan Ware’s Bench-Talk Forum. Stan, a gifted gunsmith, converted the Forum posts into an article, which first appeared on Stan’s Bench-Talk.com Website.

How to Make Benchrest-Quality Bullet Cores
by Randy Robinett, BIB Bullets

OK, Stan “made me do it”! A while back, Stan Ware asked if I’d submit a ditty on bullet-making. Here is the “picture is worth a few words” version. Below is a photo of a spool of lead wire. This is the first step in making benchrest-quality bullets. This spool of .250″ diameter lead wire will be cut into approximately 130 pieces, each about thirty inches long.

Robinett benchrest bullet spool lead BIB score 30 caliber

The Core Cutter
Here’s a really neat machine built by my Uncle and BIG MIKE. This is the core cutter. We made it using scrap steel and borrowed the crank shaft out of a 1966 Yamaha motorcycle to get the desired reciprocating-motion slide. When properly “juiced”, this machine can cut more than 3000 cores per hour.

As you doubtless deduced, the “sticks” are inserted, then fed via gravity — straightness is a virtue here! The crank, for now, is powered by the human hand. The bucket contents are the result of loading the cutter and turning the crank wheel. This photo shows cores for 112 grain, .30-caliber bullets. There are about 2500 cores to the bucket.

Robinett benchrest bullet spool lead BIB score 30 caliber

Here’s a close-up of the business end of the core cutter. Using recorded micrometer settings, this clever design allows us to get very repeatable length when changing through the length/weight cycle.

Robinett benchrest bullet spool lead BIB score 30 caliber

The photo below provides a closer look at the just-cut cores. Note the relatively clean shanks and square, unflared ends. This bucket contains roughly 2500 cores. By contrast, a tour of the Hornady plant will reveal cores being cut and squirted via a single operation, and deposited into 50-100 gallon livestock watering tanks!

Robinett benchrest bullet spool lead BIB score 30 caliber

Upon my first tour of a commercial plant, I lost all feelings of guilt about the cost of custom, hand-made bullets. When one totals the amount of labor, “feel” and “culling” that goes into them, custom hand-made bullets represent one of the best bargains on the planet!

At Hornady, each press produces 50-55,000 finished bullets per 10-hour shift. By contrast, a maker of hand-crafted bullets, at best, may make 3% of that number during a 10-hour span! Yep, hand-made benchrest-quality bullets are a labor of love and should be purchased with these criteria in mind: 1) QUALITY; 2) availability; 3) price. There is no reason for a maker of hand-made benchrest-quality bullets to negotiate on price. His time is worth what one receives from the bargain!

Core-Making Q & A
Randy’s original Bench-Talk Forum posts inspired some questions by Forum members. Here are Randy’s answers to spedific questions about core-making.

Question by Stan Ware: Randy, a post or two back you said the cores were cut into 30″ lengths first and straightened. Why do you cut to 30″ lengths? What is the reason for this?

Answer by Randy: Stan, the wire is cut into 30″ lengths (sticks) and then straightened, following which it is fed into the core cutter and cut into the individual individual “cores”. If you look at the core cutter photo above, you’ll see a stick of lead wire sticking up -it’s toward the right hand end of the contraption. The cut cores are also “ejected” by gravity — the white “tickler” brushes the cores as the slide moves forward and dislodges the core from the cutter bushing.

Q by GregP: Randy, How do you straighten the 30″ sticks? Roll them between metal plates?

Answer by Randy: Greg, BIG MIKE may kill me for letting out the secret. WE “roll” the wire between an aluminum plate, which is equipped with handles, and the “plate” which you can see in the pic of cutting the wire. The straightening is really a drag. Eventually, we will have the new cutter hooked up to a “feeder/straightener” and the wire will be cut into core slugs right off the roll! Well, that’s the Dream….

Question by Jim Saubier: How much of a nub do you use at the end of the 30″ section? I imagine that every section you will lose a little from the feed end. Your cutter looks real slick, we are using the manual deal and it isn’t quick by any means.

Answer by Randy: Jim, Since I cut all of the sticks using diagonal-cutting pliers, the ends are, indeed, waste. However, only about 1/8th inch on the beginning end — the final core may be too short. I have attached a pic of my old reliable CH cutter. I still use this cutter for .22-cal and 6mm cores and, occasionally, an odd lot of thirties. The CH cuts very square ends which are free of bulges and/or flaring.

Robinett benchrest bullet spool lead BIB score 30 caliber

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