driftrider

This is a bit of a complicated subject, and I'm sure I don't know all there is to know about it, but here's a brief synopsis of what I've discovered while researching the topics related to rifle accuracy.

First, free-floating a barrel is kind of a compromise. Theoretically, the more the barrel is supported and dampened by the stock the better. When a gun fires the barrel vibrates at the frequency and amplitude inherent to its design. In a perfect world where conditions were controlled and consistant, a barrel that is properly supported by the stock would have much of this vibration dampened resulting in a rifle that should be more accurate in terms of small consistant group sizes than its free-floated counterpart. But this isn't a perfect world, and changes in temperature (both barrel and ambient), humidity, stock pressure due to how the foreend is support and gripped, etc... all can slightly change the shape of the stock and the pressure that it exerts on the barrel. These changes in pressure can cause the group sizes to vary, but more importantly it can cause the point of impact to shift. The solution to this problem is to free-float the barrel, thus taking the stock out of the equation. With a free-floated barrel changes in climate that effect the stock won't change the point of impact, but the barrel is now allowed to vibrate freely and with greater amplitude.

The reason why most heavy barreled rifles are free-floated is because the increased thickness of the barrel greatly reduces the amplitude of the vibrations it will experience when shot, thus cancelling out most of the negative effects of free-floating. So the combined effects of free-floating and a heavy barrel yield a rifle that shoots smaller groups than most light barreled rifles (because of reduce vibration amplitude and frequency) and with a consistant point of impact. The reason many light barreled rifles are not free-floated is because doing so would allow group sizes to become too large. Unless there is a major change in climate from sight-in to the field, any shifts in the point of impact would likely be small enough to be inconsequential on large game at normal ranges (with a well designed stock), but to a varmint hunter shooting at a baseball sized target at 300+ any shift in point-of-impact due is unacceptable.

As far as sacrificing accuracy with a lighter rifle, you may not have much of a choice. Rifles with slimmer lighter barrels are in general less intrinsically accurate than a similar rifle with a heavy barrel and the same load. As far as the potential effect of not having the barrel free-floated, I don't think it'll be too much of a problem if you sight in the rifle in weather conditions similar to the climate which you'll be hunting in, and are consistant in your technique. Just bear in mind that the point of impact might change a little from when the rifle is sighted in off a rifle rest or sandbags compared to when you are shooting in foeld conditions. The solution is to do the initial sight-in off bags then practice and fine tune from realistic field shooting positions.

Also important is finding the type of ammo that the gun shoots best. If you handload you can work up a pet load for the rifle, and if you shoot factory ammo it's a matter of trial and error.

All in all, I'd say don't sweat it too much, the accuracy will be sufficient for the application the rifle is intended for (shooting at big game). If you want a rifle for toting around all day up and down hills chasing deer and such, then you'll probably want to sacrifice a little accuracy for light weight and portability. Just don't get your expectations too high and think that it should be a sub-MOA shooter right out of the boxwith anything you feed it because that's not what it was designed for. If you want a rifle that you can and should expect sub-MOA performance from then get a good heavy barreled varmint rifle designed for that task. Life's full of compromises.

Mike