Another 50Millionths Man?

[RLHBUSL]

And constantly throwing in garbage about "but matches are won with quarter inch groups" and "yeahh but a PPC won't shoot 1/4" groups where I shoot" is completely irrelevant.

***

Getting 1/4moa accuracy from a custom rifle using short/fat bullets is dead easy.

Al,

I'm not sure if your post is intended to be a joke or if you are serious. If you are, in fact serious, can you please explain a few things.

How is it irrelevant that many experienced Benchrest shooters can't shoot 1/4 minute aggs with their custom built Benchrest rifles, when the evidence of what Benchrest shooter do in competition is presented to contradict your assertion that you can shoot 1/4 minute aggs with factory ammo? I think the fact that a custom rifle won't do it with custom loaded ammo is pretty darn good evidence that you can't do it with factory ammo. If I'm missing something, please explain where my logic fails.

Further, please explain to me how you can so easily get 1/4 minute accuracy from a custom rifle using short/fat bullets. There were many a good shooters at the Bluebonnet in New Braunfels, Texas last weekend and, of the 160 aggregates shot over 2 days, only 7 were under 1/4 minute. That's less than 5%! I think this is pretty good evidence that shooting 1/4 minute aggregates with from a custom rifle with short/fat bullets is not "dead easy." If I'm missing something, please explain where my logic fails.

I can only think of a couple plausible explanations. First, it may be that we are talking apples and oranges. If your saying that shooting 1/4 minute aggregates in a controlled environment (i.e. a tunnel) with a custom rifle with short/fat bullets is easy, then I won't protest because I have never shot an aggregate in a tunnel. But, if your saying it is easy in the real world where competition occurs, then I must be missing something. If this is the case, please explain.

Or, perhaps you are just a much better wind reader than me or anyone at the matches where I shoot. If that is what you're saying, then I can't protest because I have never seen results from a short range benchrest match where you competed. No explanation is necessary if this is your assertion.

Ryan Harrison

 

[Boyd Allen]

Al,
At the beginning of this thread, there was some discussion about a tactical rifle builder that claims that his chambers are aligned to half a tenth (.00005) and who guarantees quarter MOA accuracy, with Federal Gold Medal Match ammunition. I said that I am doubtful of that particular (the accuracy) claim, and to make the point, suggested that some of the readers and I chip in and offer to pay for a day's match fee at a benchrest match where he could demonstrate that he is building rifles that will do what he has evidently advertised. A few posts later, you kicked some dirt on my doubt (perfectly OK, we all get an opinion) and seemed to be saying that such a claim was believable and doable, and that you have done it. A little further down, I offered to pay for a day's match fee at Tacoma (Yes, I was referring to a benchrest match.) and suggested that if that level of accuracy was achieved with a .308 tactical rifle, shooting the ammo in question, that it would be good for business. Do I have it right so far? In any case, my offer still stands. If you find it so easy to do, and my doubt is misplaced, do it, somewhere where everyone will acknowledge that there is no doubt as to the veracity of the claim. I will even subsidize the effort, without the qualification that it succeed. I am offering you a chance to prove me wrong, and to be clear, I make no particular claim of expertise, or skill, but I am willing to put some money where my mouth is, as it were.
Boyd

 

[alinwa]

Ryan and Boyd,

"quarter minute accuracy" is NOT ABOUT MATCH SHOOTING! Shooting matches out on a range in all-day conditions is a test of the SHOOTER, not the rifle.

IMO you'd best have "tenth minute accuracy" for shooting a match. Many do not, but it'll have to be a windy day before someone wins with a poorly tuned rifle.

I live on a range. I've had a range in my yard for almost twenty years and have learned how to use it for testing rifles.. I also live in the PNW, this area defines "temperate." I get good testing conditions often. I don't have a tunnel but close to it. I have tuned PPC's close to hand. On any given day I can look out and say "looks like a good day for testing." And go check. If any of ten good rifles shoots dots then I can proceed in testing something else.

Yes, an accomplished shooter can 'test' during a match but I can't, I need repeatable, usable conditions.

And I have them.

And I can and do shoot lots of quarter inch groups/aggs under controlled conditions. BTW, If the shooters at New Braunfels are shooting "quarter minute rifles" then they should be agg'ing well over a half inch. Why is it so hard to grasp that it takes a better rifle than that to actually AGG quarter minute groups? Varmint rifles will shoot quarter minute. Some factory ammo will shoot quarter minute.......And 308 Match ammo is some of the best in the world. In fact, of ALL the choices available I'll put 308 at the head of the pack. If I were challenged to put together a Match Rifle for competition using factory ammo I'd choose a 308 over even the 15.00/box .22 Long Rifle stuff. But still, a "quarter minute competition rifle" would be hard pressed to agg under a half minute in competition given that the shooter (conditions) adds another quarter minute, or more.

We know 5 guys with tunnels...... ask them, "can you shoot smaller groups in the tunnel?" or "Would you say your rifle is capable of better accuracy than match results seem to indicate?"

It takes an awful good shooter to assess a rifle's potential at a match.

al

 

[RLHBUSL]

a "quarter minute competition rifle" would be hard pressed to agg under a half minute in competition given that the shooter (conditions) adds another quarter minute, or more.

Al,

The quoted portion above explains everything that I was missing. When someone tells me that they have (or can build) a rifle that will shoot 1/4 minute aggs - I automatically assume that someone is actually shooting the rifle! What I now understand you to be saying is that you have (or can build) rifles that are CAPABLE of shooting 1/4 minute aggs - not that actually WILL shoot 1/4 minute aggs.

I apologize if this comes across as smart a$$ed - it's really not intended to be - I'm just trying to understand what you are saying. I think I do now and it makes much more sense.

Ryan

 

[Wilbur]

I quit throwng the BS flag when a young fellow unloaded his 22-250 and factory ammo at Bristol and shot some unbelievable groups - repeatedly. He had sandbags but not really.....As I recall, it was a Savage.

All this while I was trying to get my PPC to shoot something, just anything, less than a four with carefully loaded and deadly accurate handloads. This event contradicted in whole all I know. I was able to block most of it out but my conscience (like I have one) will no longer allow me to call BS as fervently as I once did.

 

[Vibe]

I quit throwng the BS flag when a young fellow unloaded his 22-250 and factory ammo at Bristol and shot some unbelievable groups - repeatedly. He had sandbags but not really.....As I recall, it was a Savage.

All this while I was trying to get my PPC to shoot something, just anything, less than a four with carefully loaded and deadly accurate handloads. This event contradicted in whole all I know. I was able to block most of it out but my conscience (like I have one) will no longer allow me to call BS as fervently as I once did.

For some reason this reminds me of a shooter who for years kept writing to Guns & Ammo about the 3/4" groups he could get at 500 yards with his Contender pistols. The short version of this story is that they got tired of calling BS on his letters to the edititors and challenged him to put up or shut up...They devoted a pretty large artical to it. They had to after he pulled it off with not one but 3 diffferent guns in 3 different calibers. They were 3 shop groups, but he was consistent. Just because it's hard to believe does not always mean it's BS.

 

[MColeman]

Carolyn just puts her rifle in the dishwasher when she get back from a shoot, puts it on Sanie Rinse and she is good to go.

Why ain't you helping out in the kitchen as a good husband should? I miss seeing you guys at Kelbly's.

 

[Al Nyhus]

Was coming home from the range yesterday after working with my 30BRX (30BR .100 long) and thought of this thread.

-If only this thing would have 50 millionths chamber runout....

-Have a special secret squirrel chamber to shoot Gold Medal Match factory ammo.....

-Off a bipod......

Tongue firmly in cheek in The Forbidden Zone. -Al

 

[glp]

Mike careful here. You hear some were offended by the code name Geronimo that was used for bin Laden??

I like the cowboys that split tenths. Unless they have a good set-up tenths are what the Indians used to live in(pun intended)

Mike Swartz

 

[eww1350]

the BS Factor...I remember when Browning first offered the "BOSS" system on their rifles...I was asked what I thought...I told them that if an adjustable tuner would work... the "benchrest" shooters would already be using it...
Well about three years after they came out I had an opportunity to play with one on a standard weight barrel 30-06...and it made a believer out of me...I had more opportunities with the "BOSS" on several other rifles and it worked with amazing results on all of them...

Eddie in Texas

 

[HovisKM]

After reading this thread for a couple of days, I just had to give a call to some friends at the Joint Special Operations Center, Special Missions Division, Special Weapons. They have an indoor and underground range. I asked a simple question...."Have you ever had a tactical weapon that averaged 1/4" for three or five shot groups for five groups, with factory, specialty shop loaded or goverment ammunition....any caliber...but most interested in .308/7.62 Nato". After he got done laughing.....NO !!! Millions of rounds and thousands of weapons....good enough for me.

Are there flukes...yes...but were talking about a guarantee...not flukes. If this was real...the goverment would probably waterboard him for secrets and disect his brain to figure out how he does it.....I wonder why he just laughed instead.

This kind of reminds me of companies that would send products to soldiers or units for free and then claim in their advertising "Used by the U.S. Military".....painting the roses red....

Hovis

 

[Vibe]

the BS Factor...I remember when Browning first offered the "BOSS" system on their rifles...I was asked what I thought...I told them that if an adjustable tuner would work... the "benchrest" shooters would already be using it...
Eddie in Texas

In fact I think they already were.

It came to mind that where I work we use shims to make some adjustments. When I found a source for 0.00025" shimstock I was a very happy camper, as the 0.0005" was simply too coarse to be completely effective.

 

[Nader]

Nader.....Wyatt says your going down at the Hog Roast![/QUOTE]

Jeff,
It will be good to see you both after a long winter. Tell Wyatt I have a new "secret weapon". I hope he likes to eat his crow with "dirt flavoring".
Joel

 

[JerrySharrett]

Opinions wanted



Butch

Butch, you want to see some half-a-tenth (50 millionths) work inspect some of Ferris Pindell's work. Jeff Summers and I were just talking about some of Ferris's master die holders and the bullet die inserts that fit into them.

For example he would make a bullet die body lower and a point-up die upper to fit on it that didn't even leave any trace of a seam on the finished bullet.

But, that was Ferris...not your everyday tinkerer!

 

[Don]

Al,
At the beginning of this thread, there was some discussion about a tactical rifle builder that claims that his chambers are aligned to half a tenth (.00005) and who guarantees quarter MOA accuracy, with Federal Gold Medal Match ammunition. I said that I am doubtful of that particular (the accuracy) claim, and to make the point, suggested that some of the readers and I chip in and offer to pay for a day's match fee at a benchrest match where he could demonstrate that he is building rifles that will do what he has evidently advertised. A few posts later, you kicked some dirt on my doubt (perfectly OK, we all get an opinion) and seemed to be saying that such a claim was believable and doable, and that you have done it. A little further down, I offered to pay for a day's match fee at Tacoma (Yes, I was referring to a benchrest match.) and suggested that if that level of accuracy was achieved with a .308 tactical rifle, shooting the ammo in question, that it would be good for business. Do I have it right so far? In any case, my offer still stands. If you find it so easy to do, and my doubt is misplaced, do it, somewhere where everyone will acknowledge that there is no doubt as to the veracity of the claim. I will even subsidize the effort, without the qualification that it succeed. I am offering you a chance to prove me wrong, and to be clear, I make no particular claim of expertise, or skill, but I am willing to put some money where my mouth is, as it were.
Boyd

"Extraordinary claims require extraordinary proof." Marcello Truzzi

 

[mturner]

50 Millionths

I have looked at this thread here and there. I have seen a lot of comments made that are accurate, and a lot that aren't. When it comes to cutting a concentric chamber, there are a lot of misconceptions. Things like thermal expansion which can in some cases make it hard to hold a tolerance such as two holes spaced 5 inches apart to within a .0001". First of all, keep in mind that this dimension will go over with heat, and under with cold. Measure it at 70 degrees, and that's what it is, forget about how it changes with temperature.

Chambering is a totally different story. We only consider concentricity in this case. The diameters from the front to the back are never held to .00005", more like .0005" would be more like it. The headspace has a tolerance of about .004", but the best I ever shoot for is .001" on rimless, or .0005" on my rimmed 30-30 cases. Even at that, keep in mind that I face each rim to .0555" and the distance from the boltface to the back of the barrel is set to .056".

Now for the facts about concentricity. In order to cut a centered chamber, there are factors which can guarantee extreme concentricity. Keep in mind that in order to find center of a barrel within .00005" that one only has to indicate to .0001" total indicated runout. Also keep in mind that temperature changes has nothing to do with finding center. The barrel may expand in diameter or contract in diameter, but the center is still the center.

Now, I'm not going to give away all my secrets, but I will tell you things that will make it hard to accomplish concentricity within .00005".

1 - not boring the chamber as described by Jackie Schmidt will result in poor results, so please take his advice here if you want excellent results. You say "well my removeable bushing fits snug", who cares, I can bend the skinny tip on your 6mm reamer at least .002" with thumb pressure.

2 - using a typical .00005" indicator can give less than satisfactory results. I use a better method. My system will move the indicator needle one inch when concentricity is at a half thousanth, so getting extremely close is simplified.

3 - decreasing the sensitivity of your .00005" indicater with a stylus that is 3 times longer than the stock stylus length will make a reading of .00005" actually be .00015".

4 - If your indicator won't show the tiny lift in the spindle when rotated cause by the oil film, then you're not there.

These are facts, not opinions.

At Turner Technology, Inc. Warren and I produce dynamic balancing machines that measure linear movemnet down to one millionth divided by 250. That's 1/250,000,000 of and inch. There was a time that I actually put one of our sensors on a indicator stylus. The idea was to indicate a chamber down as close to zero as possible. Warren watched the computer screen and looked for the perfect number of 128, or centered between 0 and 256. I would be off, and need to tighten a jaw just a little. At the slightest amount of pressure, he'd say "your off the scale, go easier". I'd tweek it back the other way, and he say "now your off the scale the other way, easier". Needless to say, I would have pulled all my hair out to tighten a lathe chuck down to such small tolerances.

Michael

 

[Boyd Allen]

Michael,
A comment on headstock bearings of lathes that are commonly used to chamber barrels, and the practical limits that they enforce.... please.

 

[mturner]

Well, in my opinion, the preloaded tapered roller bearing will have tighter clearances than babbit type bearings. I've heard the old South Bend lathes with babbit bearings are very smooth, but some have a lot of wear or clearance. My indicator will show about .00005" spindle lift when rotated, and this is with preloaded tapered roller bearings. I settle the spindle to the bottom every 90 degrees of rotation with a light bump on the top of the chuck with my hand. I believe a lathe with oil pressure fed bearings could be the ultimate. I assume they exist.

Michael

 

[Boyd Allen]

What kind of lathe are you using?

 

[mturner]

It's just a Tiawan made lathe, but the main thing is it has been blueprinted. Totally tore the head stock down, replaced all bearings, and preloaded the tapered bearings. Tail stock is blueprinted and shimmed to be very well centered to spindle. This lathe has the 3.25" spindle bore, so that makes it real nice for gunsmith work, and means it has extremely large roller bearings. We bought it new, so I wasn't rebuilding it, I was simply setting it up the way Americans would have. Even replaced the motor with a well dynamically and electrically balanced USA motor. Not anything wrong with the basic castings, as this lathe is extremely heavy. They just don't pay attention to detail over there.

Michael