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View Full Version : pacecil, tuner numbers!



TangoTwo
01-26-2008, 06:53 AM
Cecil, one of the guys over at Rimfire Central has done some testing of his new tuner. You may be interested in taking a look. Seems to substantiate that tuners will work. Link adress below.



http://www.rimfirecentral.com/forums/showthread.php?t=202864


Ken

pacecil
01-26-2008, 08:39 PM
I hadn't seen any testing before that was this good. It does seem to confirm a tuners effect. If you study the groups you can even see the vertical that went away as group size decreased. Before the tuner was added he said the gun was grouping at .253" at 50 yards. When the tuner was added it appears groups increased somewhat but it's not clear exactly how much - it could have been as much as 100%. After tuning to one of the best sweet spots groups dropped to about .134" (converted to 50 yards). So I would call the improvement a reduction in group size of .115" at 50 yards. This is much larger than the improvement I said you should get. Shows you how wrong I was, and the value of having some numbers.

My estimate was based on having a velocity spread of 40 fps. His spread was probably less than this but I'm not claiming this is why I was so much in error. For the moment I'm just going to have to say: y'all was right and I was wrong! I think everybody has to admit now, MKnarr has one super gun - I've never seen a rimfire average .134" groups at 50 yards.

Beau
01-26-2008, 09:13 PM
I don't see his averaging .134 at 50 yards. First, it would be hard to convert 25 yards to 50 yards based simply on that math of angles. Second, I don't really see anything that can be converted to an average. Third, is this a statistically valid sample?

tim
01-26-2008, 10:44 PM
I hadn't seen any testing before that was this good. It does seem to confirm a tuners effect. If you study the groups you can even see the vertical that went away as group size decreased. Before the tuner was added he said the gun was grouping at .253" at 50 yards. When the tuner was added it appears groups increased somewhat but it's not clear exactly how much - it could have been as much as 100%. After tuning to one of the best sweet spots groups dropped to about .134" (converted to 50 yards). So I would call the improvement a reduction in group size of .115" at 50 yards. This is much larger than the improvement I said you should get. Shows you how wrong I was, and the value of having some numbers.

My estimate was based on having a velocity spread of 40 fps. His spread was probably less than this but I'm not claiming this is why I was so much in error. For the moment I'm just going to have to say: y'all was right and I was wrong! I think everybody has to admit now, MKnarr has one super gun - I've never seen a rimfire average .134" groups at 50 yards.

Cecil, you now realize what just about anybody that shoots in matches has known for some time and you've wasted untold amounts of time and energy and probably steered a few newby's down the garden path because of it. Listen to father Kenneth my son, your education has just begun.:D

MKnarr
01-26-2008, 10:52 PM
Beau, you are correct, the rifle will not shoot groups of .134 with any regularity at 50 yards. I recently tested 4 lots of 2007 Eley Match EPS at 50 yards. The lot I ended up buying shot groups of
0.273
0.178
0.118
0.379 one bad shot
0.279
0.166

for an average of .232. This compares to .253 average for 6 groups with a different lot of Eley Match EPS that I was using pre tuner. Due to the weather and work, I have not been able to shoot for weeks so I don't know how the rifle will shoot the old lot with the tuner.

pacel, I originally reported a reduction of about 30% with the tuner but I did say I didn't expect that to continue after further testing. I am hoping for a long term improvement of 10% which in the benchrest game is welcome.

pacecil
01-27-2008, 05:00 PM
I stand corrected, but I also see where I wasn't so far off after all.

A tuner effect of 10% to a .253 average is getting closer to what I've observed. Actually in the testing I've done with a tuner the average effect I saw was 7%. Truth is I'm not sure tuner effect should be given as a per cent of group size. I think it may have just a value or number for each particular gun or ammo.

Tim, Gee I hope I wasn't wasting any of YOUR time and energy - or for that matter I hope I wasn't wasting mine! When you come down to it though, I sometimes think a lot of the time sitting in front of a computer is "wasting time"!

tim
01-27-2008, 08:15 PM
Heck no not mine, I got one of them new HP 'puters with the latest BS filter installed.:D Another way to look at the results, ask somebody that just finnished a match if that 248 could have been a 249 or the 49 perhaps a 50.
Also, have you entertained the remote possibility thay you are using equipment that is just not up to the standards you might otherwise believe and your results are being compromised? Without getting out there to actually witness what goes on at an event with a large number of highly tuned guns you really have somewhat of a marginalized sample to draw from.