Max,
Your English is just fine. It is far better than most of us can use any foreign language.
This, I think, is what will work. First of all, for short-range benchrest, both Wayne Campbell and Jack Neary are very knowledgeable. More knowledgeable than 99.5 percent of the people who post here.
Aside from being a world-class competitor, Wayne Campbell is a professional gunsmith, who knows both the tools needed to build rifles, and their use. And Wayne is very willing to help people. I was loading next to him a match just after he won the World Championship, and as you can imagine, there was a stream of people coming up to him, asking questions. Some of them were pretty dumb questions. And Wayne, being Wayne, was trying to win the match, even though it was just a regional shoot. But he took the time to deal with all those people asking questions, with both grace and good answers. I don't know Jack Neary, but I imagine he is the same way.
So first of all, I would take very seriously any advice they give you.
Secondly, there are a number of people who post regularly to BR Central who don't even shoot benchrest. Another thing we're not going to do is name names, that is, to tell you who on BR Central is very knowledgeable, and who just gets their information from rumors. It is your job, sadly, to figure that out.
Most of us fit in between, we have some real good information on some things, not so good on others. And even we can't always tell the difference about what we know.
Finally, BR Central is not really a place to help you become a better competitor, a better pure shooter. There is a story about Carlos Hathcock, a legendary U.S. Marine sniper of the Vietnam era. He was asked a technical question about rifles, and replied, "I don't build them, I just shoot them." That's probably a good way for someone who wants to be a world-class shooter to think.
The people who post here have a love of rifles, especially accurate ones. More than a few build their own rifles, and I suspect, get much of their pleasure from doing well with the rifles they build. If someone asked me whether I would rather get a top-ten placement at a National match with a rifle I built, or win outright with someone else's rifle, I'd have to think about it.
Now I imagine a number of people have sent you personal messages. Again, you're going to have to figure out who, if any, has any additional knowledge over Wayne Campbell or Jack Neary. And just in case those two gentlemen gave you different answers, I'd take that to mean both reamer grinders are good rather than one is better than the other.
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So if you have a love of why rifles are accurate, I think Benchrest Central is a wonderful place to be. If your primary goal is to become a better competitive shooter, I don't think we'll be too much help. As I'm sure you've noticed, the world-class shooters don't post that much here. It is hard to communicate their knowledge with words -- except "practice, practice, practice until you've figuered out just how much a gentle change in wind moves a 65-grain, 6mm bullet.
Best Regards,
Charles