Hi Alf,
This is a topic that can bear some discussion from several angles. The concept of drive bands and grooves is as old as the hills as you have pointed out. Nothing new there. What was new, when we applied for the HV/FN patent in 1996, was the execution of the design to precisely incorporate certain parameters that were not applied to small arms projectiles at any stage in the past.

It is important to distinguish between drive band bullets and grooved bullets. They are dissimilar in one very important aspect. With a grooved bullet, the ogive encounters the rifling first and has to be engraved before the shank of the bullet enters the bore and the advantage of lighter engraving pressure occurs. A drive band bullet has the advantage of light engraving pressure from the get go. By the time the drive band bullet is fully into the bore, it is already moving much quicker than a grooved bullet.

As we all know, all rifled barrels have two precisely controlled dimensions - the bore and the groove diameters. If any kind of accuracy is to be hoped for, a bullet must conform to at least one of these. Band/groove bullets fall into three categories and can easily be placed in these categories if a picture of a recovered bullet is studied.

1. Grooved bullets conform to the barrel groove diameter and the grooves in the bullet shank do not bear any relationship to the barrel bore diameter. This is clearly seen on a fired bullet where the lands of the barrel has either not touched the bottoms of the grooving, or the lands have also engraved the bottoms of the grooves to a greater depth. I am not aware of a grooved bullet that is manufactured to SAAMI / CIP tolerances in both bore diameter and groove diameter. I am willing to stand corrected on this.

2. Some drive band bullets are manufactured with heavy drive bands at barrel groove diameter and the body of the bullet at more or less than barrel bore diameter.

3. Some drive band bullets such as our HV, SP and FN ranges are manufactured with very precise relationships to both barrel bore and groove diameters. In this respect, we introduced a new concept in 1996. Today there are only two other manufacturers that also attempt do this and both have been manufacturing for less than 18 months.

There are several other small innovations we have incorporated into our bullets that we still do not see in others after 8 years in the market. Please pardon me if I do not wish to elaborate on that.

Norbert,
Less barrel wear? Absolutely. Flame erosion is a function of temperature in combination with pressure. With HV, SP and FN bullets, the lower engraving pressure allows the bullet to enter the bore much further before the pressure curve peaks. Maximum pressure occurs with the bullet almost three times further down the bore compared to grooved or smooth bullets. The result is lower temperature immediately in front of the chamber and almost three times the surface area of bore to absorb the temperature compared to other bullets. In SA we have seen several times that hunters who cull venison for the market and who used to completely wear out a 22-250 or 223 in one season, now shoot for three seasons or more with our HVs. This shooting is also at much higher speeds than before. 223 Rem rifles run at 3800fps with a 40 gr HV and 22-250 rifles at 4100 to 4300 fps.

I did a test whereby I fired factory ammunition at 4000fps from a 220 Swift. Temperature on the outside of the barrel just ahead of the action was measured at the start. The rifle was fired every 30 seconds. The bolt was left fully open between shots and closed just before each shot. After 10 shots, we waited one minute and measured the temperature again. The rifle was allowed to cool to the base temperature and cleaned. We then repeated the test with HV bullets loaded to 4400fps. The ten shot temperature of the initial test was reached several seconds after shot 39.

Your comment "If realized to extrem low values, the burning of the powder may be influenced in a negative manner" is absolutely correct. This is why we recommend powders on the faster side of the spectrum and the use of magnum primers with HV, SP and FN bullets.

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Alf,
I have some mono-metal grooved HP's from a gunshop in namibia where they were made.
Beautifully made, I cant come up with a single measurement, bore riding or groove, that makes sense with them.
I'd love to send you a few to look at and see what you think. If interested send me your address via e-mail.

Alf,
Our business started in 1979 when I registered with SAPS as a gunsmith and arms dealer. Up to 1992 I concentrated on building custom rifles and handguns for impractical pistol shooting. Once a year I used to take a group of customers out to a particular farm for a selection of plains game hunting.

In 1992, I came very close to losing a Kudu due to a bullet failure and, after a four hour follow-up, eventually shot it with my carry gun (45ACP). When James, the owner of the game farm arrived, I told him that, from 1993 forward, there will be a better way. I had seen my share of hunts that went wrong due to no fault on the part of the hunter other than his choice of bullet.

I had been interested in manufacturing bullets for some years before that but that incident became the catalyst for the process that is now the GS line of bullets. Most of the remainder of 1992 and 1993, up to October when we launched, was spent on R&D of the HP range. The first launch was with a range of 32 bullets. We stated then, as now, that we will exist to improve our customer's success in hunting and shooting.

I remeber being shocked rigid when I saw the first report in Magnum of Barnes X bullets. I could not figure out how anyone in the USA could possibly know about what we were planning, let alone get into production so fast. A bit more thought and research proved that Barnes had been doing the X bullet in the USA for a while and, due to the embargo, they had just not reached our shores yet.

The HV range followed the HP range logically, to solve the existing problems of pressure and bore fouling that occur with monometal bullets and to make our bullets more reloader friendly as well.

The FN range addressed the shortcomings of solids that were either failing as a result of poor construction, or deviating from the path into the target, due to designs that were approaching a century without significant improvements.

One thing led to another and, in 1999, after two bad business decisions in the preceding four years, I came very close to losing the business. I decided to call it a day and retire from the arms business. The girls, Gina and Jani refused to allow this and launched their business, taking up where I left off and launching their company internationally. I have never professed to be good at business and resented doing any kind of paper pushing. They have proven to be ten times better at running stuff than I ever was. Jani moved on to a refrigeration business with her husband and left Gina to continue with GS Custom.

I enjoy taking care of the technical stuff and it is great fun expanding the range of bullets. There is all that horrible testing on the range and in the field that has to be done by someone. I will say one thing and that is that bullet making has been an incredible learning curve for us. No two days are the same and every day brings something interesting.

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