The Stock Market

Guns Magazine, Nov, 1999 by Jon R. Sundra

PLASTIC, FIBERGLASS AND OTHER HIGH-TECH STOCK MATERIALS ARE GIVING TODAY'S RIFLES A PERFORMANCE EDGE.

Until quite recently the composition of rifle stocks was simply taken for granted. For centuries gunstocks were made of one material and one material only: wood. Preferably walnut.

Today it's a totally different story. In the span of just one generation, stocks of fiberglass, thermoplastic and wood laminate now outnumber walnut on production rifles.

There are some shooters that would have us believe these alternative materials are simply the result of a shortage of walnut, but that's not the case at all. While walnut is indeed getting scarce (read that as expensive), it's losing out to the laminates and synthetics because they simply make better gunstocks.

Let me hasten to emphasize here that by "better" I'm referring strictly to function rather than aesthetics. As far as I'm concerned, for a fine custom or presentation-grade rifle, walnut has no competition.

If you're a practical sort, however, concerned more with performance than aesthetics -- and to whom cost is also an important consideration -- then a synthetic or laminated stock is for you.

Before we take a closer look at these upstart materials, however, we must first examine just what it is that a gunstock must do before we can judge how well it performs.

Bed And Board

In addition to serving as a handle, as it were, enabling us to hold and aim the gun, a stock must also provide the barrel and receiver with perfectly matching bedding surfaces so that no bending or torque is introduced when the assembly screws are tightened. That's the theory anyway, but in fact, light- and sporter-weight barrels are generally more accurate if there's some dampening pressure exerted on the barrel at the forend tip.

Unfortunately, the only way to generate that pressure is by inletting the stock in such a way as to keep the barrel under stress. Ideally, when the barreled action is dropped into the stock, it should make contact only along the length of the receiver and at the forend tip. In other words, relative to the bedding surfaces of the barrel, the forearm should actually bow downward so there's a gap between the barrel and stock roughly halfway between the receiver ring and forend tip.

Upon tightening the front guard screw, the bowed stock is straightened, thus applying pressure to the barrel. However, this pressure dynamic is extremely difficult to achieve on a production basis, especially when the stock is a single piece of wood. More often than not, the barreled action bottoms only at the rear of the receiver tang and at the forend tip. When that is the case, stress is put on the receiver further complicating the dynamics involved.

Forces Of Nature

If a stock is composed of an inert material such as fiberglass or thermoplastic, a constant pressure dynamic can be maintained for an extended period of time, even years. With wood, however, no matter how straight the grain from grip to forend tip and no matter how weatherproof the finish, it will slowly absorb and expel moisture (i.e., warp) as the moisture content of the wood tries to balance with that of the surroundings.

When such is the case and a rifle is set up to exert pressure against the barrel, this warping will affect a rifle's zero. I don't mean grouping ability now, I mean where on the target those groups are going to go.

I'm not talking warpage of a couple thousandths of an inch and an ounce or two of pressure; I mean serious movement -- as much as 1/8" and 30 lbs. of pressure towards or away from the barrel. You can actually see warpage on stocks where the barrel is free floated and there's a gap between it and the sides of the barrel channel at the forend tip.

I have owned rifles that in January would have their free-floated barrels smack in the center of the channel with a uniform 3/32" gap along both sides, and in August have one side touching at the forend tip! That's a lot of movement and a lot of pressure.

All major gun manufacturers today float their heavy-barreled varmint/target rifles because not only is such a stock easier to turn out on a production basis, but stout barrels shoot just as well floated as they do fully bedded. Sporter-weight and Ultra-light barrels, however shoot better when pressure bedded, so most makers continue to set up their stocks -- whether they be one-piece wood, laminate, fiberglass or thermoplastic -- to exert dampening pressure at the forend tip.

The easiest way to do that on a production basis is with a pressure band of raised material in the barrel channel at the forend tip. In effect, this raised band produces the bowing effect needed to generate the desired pressure.

Now that we know what a stock is supposed to do, let's see why the ones consisting of a one-piece chunk of wood are fighting a losing battle in their effort to fend off the upstart alternatives.

From Wood To Fossil

In the production rifle category, injection-molded stocks alone now outnumber those of wood. Looking to the Savage line, for example, we find that about three-quarters of their respective offerings sport injection molded stocks. While the molds required for injection molding are very expensive, the cost per unit once the stocks are being spit out is very low - much lower than for even a crude hardwood stock.