Originally Posted by Canadian Bushman
What is the chance of a barrel tuner not increasing accuracy?
actually pretty easy to mess things up if not installed properly. First of all it must be very concentric with the bore just like a brake should be. Secondly the method that it works off of (there is two or three types) has to be able to handle the harmonics the the ignition and bullet energise. I'd prefer the counter weighted ones as you can easilly make different weights for it.
The ones I did were for 50 yard rimfire benchrest, and I actually built two similar ones but out of radically different materials. But they are the same principal as a centerfire. The third one I built was a weighted one, but how it shot I don't know for sure to be honest with you. The tuner I designed and built shrank the five shot group size by almost 50% with no other changes. But what was really nice about it was that we could change to Green Tag for practice and actually cut those groups by close to 60%! Another little thing I liked about the tuner was that you started out shooting good with a cold barrel and it changed very little if not much at all. The old Browning Boss system worked the same way, but was not quite as sophisticated as the ones on the market today.
There's also a cheap rubber sleeve affair that seems to help reduce harmonics a good bit. (don't remember who made it, but it simple and cheap. Another way is to actually instal a metal insert in the stock that's about an inch back from the end of the forend. Then you use a nylon tipped set screw to exert a little pressure on the barrel (will change point of impact a little bit). Some guys have gone so far as to use three screws 90 degrees apart. Have never tried this one, but a few have used it in the past.
never hurts to experiment a little bit!