On Taylor Throating
I recently received an email asking my thoughts on Taylor Throating - the procedure where a reamer removes the rifling for roughly a half-inch past the forcing cone, and the edges of the lands are chamfered to match. The concept is to make an area that allows the bullet to 'stabilize' after jumping the barrel gap, but before entering the rifling.
Taylor Throating is somewhat controversial, with some holding it to be the greatest thing since peanut butter, while others claim that it is pure snake oil. In the interest of full disclosure, I don't offer the service - even though I've invested in the equipment - simply because I remain agnostic regarding its value.
Reports of miraculous results seem not to have occurred under controlled conditions. By that, I mean tested on a gun without any changes other than the throating. The glowing reports tend to be from those who had a lot of other work done at the same time, including timing and forcing cone changes. It's hard to say if the positive reports are in fact due to the throating, to other work, or to something subconscious on the part of the shooter doing the testing.
I've experimented with Taylor Throating on a properly maintained Dan Wesson .357, using several 6" barrels, and shot by two different people (one of whom was your author); the results were inconclusive. When a barrel with just the throating was tested, there was a slight increase in accuracy - but it was not consistent, nor large, enough to rule out normal shooter performance variation. A barrel prepped with a proper crown and an 11 degree forcing cone (as pioneered by Ron Power) achieved a definite positive result, roughly equal to what is said to be expected by some Taylor advocates.
My preliminary opinion, based on my admittedly limited experience with the technique, is that a proper forcing cone and a perfect crown still produce the most noticeable accuracy improvement. Of course, this is assuming that the gun is in perfect condition (timing, cylinder/barrel alignment, etc.) to begin with.
There are a couple of specific conditions where Taylor Throating might prove useful as a salvage technique: when the barrel/cylinder alignment is just a hair off in the vertical axis, or where there is a noticeable constriction in the area where the barrel screws into the frame. In those cases accuracy changes in excess of what would normally be expected have been reported, and may be legitimate. There are also some indications that it may extend the useful life of a severely worn barrel, where replacement is difficult or economically unwarranted.
Some specific downsides have been identified, however. If the throated area is even a tiny amount bigger than the chamber throats (or the bullet diameter), lead bullets will suffer "blow by" and gas cutting - severely leading the barrel, and definitely decreasing accuracy.
In the end, it's your choice. I'm not ready to call it a fraud, but neither do I see a definite positive benefit to having it done. When I come up with solid evidence on either side, you can bet I'll report it here!
-=[ Grant ]=-