Fender Bullets string ends (Fig. 1, above), and Fender ball string ends (Fig. 2, below). Note how the string wire must loop around the ball ends in Fig. 2; no such loop is necessary in the bullet-end design.
You know, when you see Fender “Bullets” and “Super Bullets” electric guitar strings there on the display rack at your local retailer, the names aren’t just a gimmicky play on how fast, straight, true and deadly your playing will be when you use them. There’s actually a lot of Fender innovation and history behind them.
In a nutshell, “Bullets” and “Super Bullets” strings are so named for the bullet-like terminus of their bridge ends, which differ markedly from the “ball-ends” of conventional electric guitar strings. They are designed to impart greater tuning stability and sustain through improved string-bridge contact.
With its long history of instrumental innovation, it’s no surprise that Fender eventually turned its attention to guitar string design. Specifically, Fender engineers of the early 1970s were aware that the standard ball-end string design that had prevailed until then presented very specific tuning problems, especially on tremolo-equipped guitars.
The problems lay in the design of the string themselves. On ball-end strings, the core wire of the string wraps around a separate piece, a tiny metal “ball” (more like a very short tube, really; see Fig. 2 at right). This creates a small V-shaped area of “slack” fit in the two places where the wire loops around the ball. At normal string tension, this “slack” wire loop is taut and unbent, and the ball end is prevented from completely abutting the bridge plate (or, in the case of a Stratocaster, from sitting completely snugly in the trem block channel). This fit isn’t the most optimal form of contact between the end of the string and the bridge.
An effect of the ball-end design is that when bending a string, the wire in that small slack area bends slightly, allowing the ball-end to seat itself more closely against the bridge. Then, when “diving” the tremolo, tension on the bridge end of the string is briefly released, causing the slack area to attempt to spring back to its original un-bent position, only to “re-bend” when bending the string again. The problem is that when the string returns to tension, it might or might not be seated against the bridge exactly as it was before, which means there’s a pretty good chance that it will be slightly out of tune. Another problem is that, on Stratocaster guitars, ball ends often get wedged in the tremolo block channels pretty tight, making them difficult to remove when changing strings.
Fender engineers sought to remedy this situation in the early 1970s by designing a new string end that optimized contact with the bridge. They did away with the ball-end design entirely; in fact, they did away with whole idea of winding the string around a separate end piece.
Their solution was to attach a tiny cylinder of solid steel plated with zinc shaped like a bullet to the end of the string in a tidy-one piece construction (see Fig. 1 at top right). There was no loop and hence no slack, and the business end of the bullet made tighter and more uniformly solid contact with the bridge. Further, the nature of the precision-machined bullet-end design meant that the string returned to the exact same position every time, greatly improving tuning stability even after heavy tremolo use.
Above, a Stratocaster tremolo block cut away in cross section shows how a bullet-end string fits more solidly and precisely in the string channel than a ball-end string, imparting advantages in both tuning stability and sustain. Below, a 1979 Fender ad for Super Bullets features jazz great Larry Carlton playing a decidedly un-Fender-like guitar.
The new string-end design was especially well suited to Stratocaster guitars because the bullet ends fit far more precisely into the tremolo block, closely fitting the circumference of the string channel, and they slipped out easily when changing strings.
Fender introduced its bullet-end electric guitar strings circa 1974 under the name “Super Bullets.” They were available in pure nickel and nickel-plated steel versions for electric guitar and bronze-wound for acoustic guitars. Although Super Bullets electric strings could be used on many different guitars (Larry Carlton touted them in a 1979 Fender ad in which he was pictured playing a Gibson guitar!), they were especially popular with Stratocaster players.
Super Bullets existed largely unchanged until the early 1990s, when Fender switched from zinc-plated steel to brass for the bullet ends. Brass had the additional advantage of imparting improved sustain. By the mid-1990s, Fender was offering pure-nickel bullet-end strings dubbed “Bullets,” nickel-plated steel bullet-end strings dubbed “Super Bullets, and bullet-end acoustic strings in bronze and phosphor bronze versions. Bullet-end stainless steel strings appeared in the late 1990s.
Today, Fender continues to offer its classic bullet-end electric guitar strings in the strong, slender forms of its pure-nickel 3150 Original Bullets, which are ideal for vintage-style tone, and nickel-plated steel 3250 Super Bullets, which offer characteristic tonal power and durability (both pictured below).