As with any situation in the precision rifle community, we need to beware the terms ‘always’ and ‘never.’ We can’t know what sort of situation we might face in the field, and we don’t want to rely strictly on anecdotal advice to guide us should we encounter a situation with unusual demands.
For instance, what happens when the target you are engaging lies beyond a fence, and the only available support for your rifle is the fence in front of you? We’ve been told to never rest our barrel on an object while shooting, but what if there’s no other way to effectively take the shot?
There are three things that we must first understand before doing so, the first being that when we rest our barrel on an object, we are actually bending the metal and disturbing the harmonics of the barrel. When we place the barrel against an object, the barrel will naturally move/bend away from the object on a molecular level as the barrel vibrates when fired. Second, we need to know that the amount of pressure we apply to the rifle while the barrel is resting on an object will greatly affect how much the barrel bends away from the object, thus greatly increasing the amount of error we see downrange.
Lastly, we need to know that the amount of error we will see downrange is also in relation to where the barrel is resting on the object. For the serious, tactical precision shooter, you can take your rifle out to a controlled rifle range and document your data when resting the barrel on an object less than half an inch in diameter (or on a fence). Take note of where the rifle barrel rests, and document the changes in bullet elevations. You can document the bullet impacts when the rifle barrel rests near the base (closest to you), the middle portion of the barrel, and the forward section of the barrel. This should be done at the 100, 200, 300, 400, and 500 yard lines.