Reverse taper

Martin
A number of the items in your photo are frequently made from non-magnetic materials. Is that the point you are trying to make?

Is there some rule that info from tuner gurus has to be dispensed in riddles? With all due respect your posts are every bit as confusing as a former poster's on this site.

Don
 
Magnetic Bullets

Don:
I tried magnetic bullets, but couldn't get enough powder in them little 22 cases, for the bullet to get out of the CM barrel. Haven't tried it on these new fangled SS barrels yet.
 
Landy

All I expect from tuning is eliminating the vertical spread. I've always thought the horizontal was wind or light conditions. Yes, I know, wind and light can also give vertical, when tuning I try to pick good conditions or shoot inside. What I'm trying to do is get them all to hit at the same height on the target. This way, I rarely have a problem with horizontal.

Tuning is so hard for me, once I set the tuner, and as long as I'm shooting the same lot number of ammo, I rarely turn the tuner again until something convinces me the gun isn't working.

Martin,

Back in 1993 I tested a magnet mounted to a worm threaded block bedded in the stock, under the barrel, near the end of the forearm. I could adjust the screw/magnet in and out, for a total travel of about two inches. Turning the screw would change the point of impact of the bullets, but I gave up on the idea. Decided to go on a barrel buying spree and finally found one that shot lights out, for a while.

Tony
 
pacecil said:
If you will look at Varmint Al's results you will see that he was not able to show an improvement in a reverse taper barrel by adding a tuner. The reverse taper was best, and better than other barrels, without a tuner.

What do you say about this Martin?
Click to expand...

Cecil
If you look at Varmint Al's work on the reverse taper he lists the amount of vertical for the distance being shot.It wasn't zero so I see room for improvement and the tuner being used was a fixed 8 ounces if I read it right?
The results might have been better if he went in 0.5 ounce increments.

If you look further he also did a FEA of my rifle and it shows the barrel always on the down swing wiht or without a tuner attached.That rifle shot 4 world records with a 6 ounce tuner on it.I think the modeling is good but you need more input to get it exact.
Waterboy
 
Doesn't the added muzzle weight of a reverse taper act the same as a non-adjustable tuner?
Isn't that what the Sporter profile barrels accomplish?
 
Lynn said:
If you look further he also did a FEA of my rifle and it shows the barrel always on the down swing wiht or without a tuner attached.That rifle shot 4 world records with a 6 ounce tuner on it.I think the modeling is good but you need more input to get it exact.
Waterboy
Click to expand...

lynn,i think think al is incorrect in only 2 things with his test,in my testing i can get any barrel on the upswing without a tuner no matter what the contour.from a 1.450 tapered to 1 inch,1.25 regular taper and weak middle.but have never tested a reverse taper.and the extent of velocity corrections is much much larger then al predicts as well.but he has been right on the money on everything else compaired with real life testing . tim in tx
 
History Repeats itself

Back in the Mid 70's, many of the Silloquet shooters, used a barrel exactiy like the so called new Sporter style barrel. It helped the with the rifles balance, and they were able to counter sink the muzzle to improve accuracy, while maintaining their sight radius. History often repeats itself.
 
Lynn said...If you look at Varmint Al's work on the reverse taper he lists the amount of vertical for the distance being shot.It wasn't zero so I see room for improvement and the tuner being used was a fixed 8 ounces if I read it right?

Nope you didn't read it right - He applied three tuner weights to the reverse taper barrel from about 5 oz up to a pound. They reduced vertical but never got it down to what the bare barrel was. The tuners might have been said to get vertical close to what it was from an .8 and 1.0 diameter barrel but that's about all. Overall I would say a reverse taper barrel with one of the lighter tuners would probably perform about same as the straight barrels.

On another subject....Martin made some comment about attaching magnetic weights to his barrel, and then I assume moving these weights around to see what the effect was. Some of you have twisted this around to meaning using the magnetic force to move the barrel or bullet. I understand some of you hardly take time to read what Martin writes, and I know he writes some pretty weird stuff, but back off and at least try and understand what he is saying before you come up with your weird response!
 
Pacecil
They reduced vertical but never got it down to what the bare barrel was.

If they never got it back to square one how did they reduce the vertical?

Waterboy
 
Tim In Texas
Tim if you look at his website it never shows my barrel on the way up like we want it.I am thinking most of the guns we shoot against have a similar length and we might need to go to a shorter barrel like Bob Turner used to use.
Lynn aka Waterboy
 
You are right Lynn, the word should have been, affected rather than reduce.
 
lynn ,this should turn some heads a the range

i know this sounds wacky but in your situation [you cannot cut it yourself] if you can find someone that can cut a crown at least 3 inches up inside a recess then go to the range,take a good square cutting chop saw and trim it back at the range,deburr it and shoot it again until you get almost to the correct amount of flip at 100yds stop there and load up the saw and head to the 1000yd range .then fine tune the 2 loads to converge at 1000 yds.just as a gauge for you, my dasher ,when 2 loads are tuned for 1000yds the slow rounds are hitting roughly .800 higher then the fast rounds at 100yds.that is what you want to see for the short of the target for us,for the rimfire guys this would be the infamous 42 yds or anywhere you could see the flip with the slower rounds which would assume is harder to see.its all about length in my view. good luck sirs tim in tx.
 
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fred sir

Fred J said:
Back in the Mid 70's, many of the Silloquet shooters, used a barrel exactiy like the so called new Sporter style barrel. It helped the with the rifles balance, and they were able to counter sink the muzzle to improve accuracy, while maintaining their sight radius. History often repeats itself.
Click to expand...

fred sir, i was waundering do you think they were doing the same thing we are doing now to widen the tune?did they ever speak of tuning for a wide velocity correction?or just small velocity variance? tim in tx
 
Haven't the slightest

What and why they did it, I don't know. I do know, they won a hell of a lot of events with lesser ammo,than we have today. Of course, Ammo back then, was not as lot sensitive as what they produce today. Oh for the old Orange Box Tenex and the Winchester Easy Ex's and Mark III and IV ammo.
 
Don Stith said:
Martin
A number of the items in your photo are frequently made from non-magnetic materials. Is that the point you are trying to make?

Is there some rule that info from tuner gurus has to be dispensed in riddles? With all due respect your posts are every bit as confusing as a former poster's on this site.

Don
Click to expand...

Don, those sights are magnatized, one weight affects a reverse tapered barrel. it appears on a 25" barrel that 6.0oz is too much weight. Don I know you have a couple cz sporters.put a 2 oz weight and move it from 4" from the muzzleto right at the front sight hood 2oz eliminates all verical on everyone of my cz's it does not take much weight. that has me thinking that the barrel dampners may bring a barrel alive not because they dampen vibration but just from the weight. this magnatizing is to have the weights stay in place.
 
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have not completed enough testing on this but here's something else found out.without a tuner zero your scope with a slow round 1044 is what I used. put your tuner on, a harrell's 8.6oz tuner set the tuner for 250, foul the barrel and shoot a test group with slow1044fps and faster 1082fps. did the slower go high? if yes then 2 things the rifle is capable of tuning a wide range of ammo and the barrel will need more weight. if no and the slow round shot low then a harrell's tuner is too heavy and the barrel may only be capable of tuning to slow speed ammo. if too much weight and the harrell's tuner by itself is overwhelming the barrel slow ammo will always shoot low and the opposite, to tune a wide range of ammo should happen. that's what I think anyway.
 
Don Stith, that paulownia custom cz stock you made is being used on a cz trainer. the trainer will be shot with the front sight minus the sight hood. those magnets indicated that cz will shoot some pretty good scores set up that way. once in a while there is a reason. we'll find out if the cz can compete against some custom rigs at anderson creek.I think it can.
 
Martin
Thanks for these clarifications. At least I can relate to this info. Best of luck with your ongoing tests.
Don
 
Well I see that you've been speaking of external taper.
I'd just been discussing the unusual practice of reverse taper lapping of the SMLE MkI bore.
In that instance the last fourteen inches of the bore was lapped oversize to reduce drag on the bullet. The intention being to maintain the same velocity from the Shorter 25 inch bore of the SMLE as from the 30 inch bore of the earlier Lee Enfield long rifle, both used the MkVI ammunition with heavy round nosed bullet.
Accuracy was severely affected of course, the bean counters of the day considered mass volley fire more important than individual marksmanship and wanted range at the expense of accuracy.
Later marks of the SMLE used a conventional bore and the higher velocity MkVII ammunition with lighter pointed bullet.
The older rifles were supposed to be rebarreled in 1917 but few were before the end of WW1, after which these rifles were surplused out.

Not really relevant to the OP question but a tidbit that might be useful one day.

PS
The old SMLE was a pioneer in barrel tuning. It relies on upward pressure from a spring loaded T plunger near the muzzle and an adjustable spring tensioned barrel band about mid way. When properly tuned, a round at lower than normal velocity will exit the muzzle on the up swing of vibration, and a round of higher than normal velocity exits on the down swing. The result being a controled compensation factor with minimal vertical dispersion out to 600 to 800 yards despite loose tolerances of WW1 ammo supplies.
The SMLE could print noticably smaller groups at longer ranges than its short range performance would lead you to believe possible.
Of course that much complication meant the bedding got out of whack very easily under combat conditions and inclement weather.
It worked fine on the target range but most rifles suffered significant loss of long range accuracy within a month on the line.

The same basic system might be adapted to modern target rifles with better results.
 
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