[amamnn]

There are a few things to remember when choosing FBs and BTs.


1- A FB will "leak" less gas, especially in a BR barrel when the bullet is seated so as to jam* in the lands. Less leakage means less turbulence ahead of the bullet, both in the barrel and at the muzzle, which can result in an easier tune and possibly a wider tuning node, which will make accuracy easier to attain.

If all that means nothing to you, don't be alarmed-- it probably means nothing to your particular application--much like the entire controversy of BT vs. FB in the first place.

2- A BT bullet is a better flier once beyond the range in which pitch and yaw are more important than wind bucking and true ballistic performance.

That might sound complicated, but it is really not. You can prove the principle that created BT and rebated BT bullets yourself with a Frisbee or a football. If you throw either one, especially thrown when hard as you can, and observe their flight, you will notice that at first, they tend to flail around somewhat, but later in flight settle down to a smooth trajectory. This is a good part of the idea behind a BT bullet.

A bullet meant to fly only a few hundred yards does not need to smooth out its flight, but will benefit greatly in accuracy when the tune of the barrel is such that it does not impart a bigger built in "wobble" to the bullet.

3- Bullet diameter and start pressure along with seating depth can affect the effect of gas leakage. I have bought custom made 6mm BR bullets from makers who tell me that there is no appreciable difference in group size between their FB and BT bullets. As far as I can tell they are both right and wrong in this belief.

In my 6mmPPC there does not seem to be any difference that I can see in a FB or a BT bullet when you go by group size--always subtracting the "pilot error" induced by the shooter--But-- in my 6mmBR Norma (much hotter powder charge) and my .243(6mm) WSSM (much much hotter powder charge) there seems to be a bigger difference than I can account for because of tune or recoil. In my 22 BR there seems to be such a small bevel in the BT that it makes no difference that I can see. Same goes for the .223 Rem. Same goes for the .30-06, but not for the .30BR, for some reason-- I think maybe because of the very fast powder used in that cartridge?

This all applies to ranges of 300 yards or less. I have not shot a FB bullet beyond that range, and now it is too late for me to do that experiment since I can't drive as far as the closest longer range facility.

* Jam is a BR technique that is safe and works well in custom made barrels when you know the exact measurements of your chamber and brass and can control the neck thickness and diameter of your brass reliably.