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Bob Kingsbury
06-18-2008, 08:13 PM
When a tuner is installed, and not adjusted correctly, will the groups all
be verticle or just everywhere. Will it shoot anything at all?

Boyd Allen
06-18-2008, 08:43 PM
With the two tuners that I have tried, adjusted, there was a subtile improvment in grouping. If you looked at the groups when the tuners were not at their optimal settings, you might notice the difference in group location, but there would be nothing to identify the groups as out of tune with a tuner, and while making the adjustments, there was no great difference with a tiny adjustment. In both cases, I tuned for best accuracy with the load, leaving the tuner alone, and then worked with the tuner to see if I could improve things. This is work for a day when conditions are very easy.

Dick Wright
06-18-2008, 09:34 PM
a big difference. True story...

A couple of weeks ago I was shooting one of my LV guns to check the tune before a match. I shot a few groups which were very good and decided to put on my mirage shield, just to see if it made a difference. It was coolish and I hadn't bothered when I started. My groups had been mid-ones before. After the mirage shield was attached, I couldn't make two shots touch.

I was shooting a gun with a Dwight Scott tuner. There is a hash mark on the back of the weight that I can see whilst shooting. It was pointing at four o'clock when I started. I had to move it up to two o'clock before it started to shoot dots again. I only move it a tiny bit at a time so I actually moved it three times to get it up to the two o'clock where it was back in tune.

For the mirage shield I use the red foam padding from Weaver Scope boxes. I split it in two length-wise and cut the length to fit the barrel. It weighs practically nothing. However, it weighed enough to make me re-tune the gun. The tuner weighs aprox five oz.

Dick

JerrySharrett
06-18-2008, 09:45 PM
When a tuner is installed, and not adjusted correctly, will the groups all
be vertical or just everywhere. Will it shoot anything at all?
Bob, explain your tuner. Is it threaded or clamped. is it light (<6 oz or >6 oz) or heavy?

Different tuners act differently based on weight and attachment method. For example, if it is a clamp-on and is too tight you can get some really screwy groups.

IMO, based on what I have found, a tuner can be used to take the vertical out. On the other hand, if out of adjustment, it can make groups spray. I've never been able to make a tuner take horizontal out.....that's the wind.

What I am trying to explain is that if a group is just vertical. adjusting the tuner, if it is of the proper weight, will take the vertical out. If the group is just horizontal, that is the wind and a tuner will not help, much. However, you can adjust a tuner to make groups spray like a shotgun.

jackie schmidt
06-18-2008, 09:48 PM
I do not espound on the theory that you can just stick any load in a Rifle equiped with a tuner and make it shoot competitive aggs.
What I do is find a combination that works on a specific barrel configuration. For instance, most shooters know that I shoot .237 4-groove Krieger Barrels. I have found that a Bruno Boattail jammed hard in front of a big dose of N133, will shoot at a pretty good level sans tuner.. I use the tuner to optimize the barrel', and to keep it agging if it starts to get ragged.
What I mainly look for is verticle, sometime a bullet holes worth. I can play with the tuner and usually get the Rifle shooting nice round groups.
Keep in mind, without the tuner, the barrel is in a pretty good tune. The tuner simply finilizes the load window.
Amazingly, you can make the barrel shoot pretty bad with a tuner, but not as bad as you might think. Maybe if I used a heavier tuner, I coulkd get the barrel to shoot really ugly groups, but the 5.5 ounce tuner I use has just enough weight to get the barrel as good as it will get.
It is really not that difficult. I will just lay down a couple of 3 shot groups at the beginning of the first match looking for verticle. I do not pay much attention to the conditions, other than making sure the flags are all in the same direction so no verticle is induced by a reversal. I doubt I have ever had ti turn the tuner more than 3 times to be satisfyed.

Bob Kingsbury
06-18-2008, 10:41 PM
Jackie, At the moment, I have no tuner on my gun(rail) It shot very well
.360 ten shots at 200. Very round holes. I shortened the BBL
from muzzle end about 3/4" and most of the time its more verticle
than anything else. The BBL was not removed from glued in blocks.
just wondering if its a canidate for a tuner or another problem.

jackie schmidt
06-19-2008, 02:31 PM
I do not use a tuner on my Rail Gun. I used to, but took it off.
The problem is this. A Rail Gun is the only target Rifle that will allow you to shoot 10 shots in less than 25 seconds, with the expactation that all of the shots will land in a competitive group. We found that for some reason, the tuner does not allow the barrel to settle between shots, and the results are disastrous.
Shooting a a slow deliberate pace resulted in excellent groups. My Rail Tuner weighed 18 ounces, fitted onto a 1.450 diameter barrel. I could tune it the same way I did my bag guns. But, anytime I started running and gunning, the groups would end up as big round .350+ globs. I tried several different concepts, with the same results. We even mounted a tuner on Bill Sturms Rail, with the same results.
I will admitt, this puzzles me somewhat. But, rather than fighting it, I just took the tuner off, and tune the Rail in the conventional manner.
My Rail Gun is pretty forgiving on tune, I use an isolator in the block, (round), and also a non-metalic "snubber" half way between the barrel block and the end of the barrel. The snubber actually only weighs about 3 ounces, it is machined out of a high impact rubber compound that we make small rudder trunk bushings from.
It deadens the barrel, and I have done pretty good this year with it.........jackie

Bob Kingsbury
06-19-2008, 05:47 PM
Maybe just to much mass in the barrel, compounded by the added weight
of the tuner. No time to arrest vibrations between fast shots. ???