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Taylor Thoating


cas

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Taylor Throating is simply cutting the forcing cone to a 10-degree chamfer.

I've heard a couple smith's say that, but that's not the Taylor throating I know. (and not what Mr. Taylor had in mind.)

Edited by cas
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Taylor Throating is simply cutting the forcing cone to a 10-degree chamfer. (11 degrees has been one of the industry standards for many years, although it doesn't have a cool-sounding name.)

This is not what I know of as Taylor throating either.

This was copied from Jim Strohs website. It is also how Taylor throating was discribed to me by Mr. Taylors son.

copied from Jim Stroh of Alpha Precision

Taylor Throating is offered in .22, .32, .357/.38, .40, .41, .44, .45, and .475 calibers. Essentially, the barrel throat is lengthened one and one half to two calibers, and enlarged to slightly over groove diameter. The throat serves as the throat in a rifle barrel, enabling the bullet to become perfectly aligned with the bore before engaging the rifling. The "choking" effect present from tightening the barrel into the frame is removed as well. The rifling leade is a very gentle 1 ½ degrees. On average, when tested before and after using a Ransom Rest, 50 yard groups have been reduced 40 to 50%. The improvement is there using both cast and jacket bullets. I have not detected a change in velocity using cast bullets. Before and after chronographing is within standard deviation of each test. Using jacket bullets, there is a slight loss, less than 50 fps in all the tests I’ve conducted. If the barrel cylinder gap is adjusted to minimum at the same time the Taylor Throating is done, there will not be a velocity loss with jacket bullets, usually a gain of 25 to 50 fps.

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Well, no disrespect intended to Mr. Stroh, but I would probably come up with a flowery description too, and make it sound like something really magical, if I were charging $95 to "Taylor Throat" the forcing cone on a revolver.

(Particularly considering it takes only a couple minutes' worth of effort to re-cut a forcing cone.)

Clymer makes the Taylor Throating reamer--it's simply a 10-degree chamfering reamer for the forcing cone. I'm not saying it doesn't work perfectly well, I'm just pointing out there's nothing all that special or magical about it.

Caveat emptor.

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Not to make the thread drift worse...

The origins of the Taylor throat. (I looked for this many months ago and couldn't find it. Just had Jim taylor send it to me. I guess it's not "live" on the net anymore, just archived)

http://web.archive.org/web/20020606140647/.../dad/throat.htm

Thats the expanded version of the story Jim told me over Friday night chilli at CSA a couple years back.

They were just trying to save some barrels that were about shot out and Taylor throating came out it.

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A Taylor Throat is indeed a half-inch long freebore forward of the forcing cone with a gentle leade. In theory, it allows the bullet to somewhat straighten itself out before it engages the rifling, thereby increasing accuracy when the cylinder chambers are misaligned. I have seen it. It is not just a recut forcing cone.

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I tried to do some internet research this afternoon on my own, and did a Google search using the terms "Taylor" and "throating." (Naturally, I made sure I had Google's safe search feature turned off, so I wouldn't miss anything.)

I found some interesting websites that were unrelated to firearms, and I guess I never managed to return to my research.... ;)

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A Taylor Throat is indeed a half-inch long freebore forward of the forcing cone with a gentle leade. In theory, it allows the bullet to somewhat straighten itself out before it engages the rifling, thereby increasing accuracy when the cylinder chambers are misaligned. I have seen it. It is not just a recut forcing cone.

You can easily create a "caliber-long" freebore with any forcing cone chamfering reamer, whether it's 10-degree, 11-degree, or whatever--it's simply a matter of how long you turn the reamer and much material you allow the reamer to remove.

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But does that reamer remove rifling forward of the forcing cone (toward the muzzle)? That lack of rifling and the gentle leade is what allows the bullet to straighten itself out before engaging the rifling. That barrel is a smoothbore for the first inch of bullet travel.

Edited by rhyrlik
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Well, you're certainly sold on the idea, so why not give it a try and report back to us how it worked?

Do us a favor, though--run a good selection of ammo through the gun before and after using a Ransom Rest, and have an impartial shooter who knows how to operate the rest do the shooting. If you're anywhere near Iowa, you're welcome to use my rest!

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You can easily create a "caliber-long" freebore with any forcing cone chamfering reamer, whether it's 10-degree, 11-degree, or whatever--it's simply a matter of how long you turn the reamer and much material you allow the reamer to remove.

That's not at all true. You'd just end up with a forcing cone with a huge diameter at the barrel face. To duplicate a Taylor Throat you'd start with your existing forcing cone and then go in with a rifle throat (freebore) reamer. The Taylor Throat has a section of parallel sides past the forcing cone that that basically cuts that area to groove dia. followed by a gentle leade into the rifleing. Was (is?) popular with silhouette shooters and does wonders for barrels that have a constriction at the barrel/frame threads from too much crush, (spelled Ruger).

Edited by Tom E
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If the goal is to allow the bullet to "freebore" for half an inch and then gently channel into the rifling, a simple 11-degree chamfer could be applied to open things out enough to achieve that goal. The walls in the freebore section would not be parallel, they would be at 11-degrees too, but so what? Besides, nobody has explained how a bullet is supposed to magically stabilize itself in the "freebore" section anyway. It really doesn't make sense if you think about it.

Frankly, I think there's a lot of confusing and contradictory material on the internet concerning this subject. For example, Jim Stroh says this style of forcing cone produces lower velocities, but Jim Taylor says his dad's method produces higher velocities (??). Jim Taylor gets all excited about achieving 2" groups at 25 yards--but since when is that level of accuracy any big deal?

Who knows--maybe it's real. I still would like to see this subject researched by objective experimenters who haven't tasted the Kool-Aid, and who have nothing to sell. Anecdotal commentary about improved accuracy is meaningless--the placebo effect is a powerful thing.

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Anecdotal commentary about improved accuracy is meaningless..

But it's only anecdotal if you don't know the man.

My point (the reason I came back and posted the link) is that MUCH of the mixed reviews about Taylor Throating comes from people who don't know what it really is. About two months ago I was involved in a discussion (read polite argument) with a gunsmith who was bashing Taylor Throating as a do nothing procedure and a wast of money. He stated that he would no longer do them. But as described by him, he was never doing them in the first place. Apparently there's a lot of smiths out there doing SOMETHING(?) they're calling Taylor Throating as well.

People and the internet being what it is, there would be mixed results either way, if they were all doing real deal. Throw in a large number that are doing something else entirely. and calling it the same thing, and results have no choice but to be all over the map.

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That may be true. I like the concept, though. Clymer people told me their reamer cuts a .4525" freebore. The problem is my cylinder throats are .452". Close enought for a match or will honing be necessary?

I would expect them to be fine. Nice thing is that if not, it's easy to fix.

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Mark Bradshaw asked me to review this thread and comment.

I will start out assuming the thread was about semi-autos, though the relevance to revolvers, at each step, will be obvious.

The cartridge has two functions: (1) to position the bullet in front of the freebore, more or less centered on the freebore/barrel axis; and (2) to propel the bullet into the freebore.

The freebore has two functions:

(1) to align the axis of the bullet with the axis of the barrel prior to engraving the bullet in the rifling (ideally, the freebore would only be about 0.001 inch larger than the bullet and about as long as the length of the bearing band on the bullet); and

(2) in IPSC major to give the bullet some distance to get up to speed before it begins to engrave in the rifling (this lowers peak pressure by increasing the volume behind the bullet, before the bullet encounters the resistance related to engraving, and peak pressure is reached).

The angle at which the lands engrave the bullet is a primary determinant of accuracy. If you make a table of rifle cartridges, listing them from least accurate to most accurate, and then place the land angle specified in that cartridge's specification adjacent each cartridge entry, you will find that the shallower the land angle the better the cartridge's accuracy. This shouldn't be a surprise, as a less abrupt engraving process is more likely to occur reproducibly.

Revolvers have the additional problem of transporting the bullet from the cartridge to the freebore and I suspect that if: (1) the cylinder alignment is more accurate; (2) the cylinder hole diameter forward of the cartridge is barely bigger than the bullet diameter; and (3) whatever forcing cone moves the bullet into alignment with the freebore does so more gently, then the revolver will produce better accuracy.

So, if Taylor recommended a tighter longer freebore and a shallow land angle for engraving, he was doing exactly what one should do to improve accuracy.

Wil Schuemann

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Interesting. It occurs to me that a revolver already has a significant amount of "free-bore" which the bullet has to traverse as it travels through the chamber throats in the cylinder and across the gap to the forcing cone in the barrel--this would seem particularly true with a .45 ACP revolver, which because of the short cartridge OAL requires the bullet to go quite a distance before reaching the barrel.

When you're talking about a revolver for action shooting, where reliability and functionality is more important than pure accuracy, you have to make some compromises. Most of the recognized ways to maximize revolver accuracy--(virtually no endshake, tight headspace, the barest minimal cylinder-to-barrel gap, perfectly aligned super-tight chambers with no wiggle in any direction as the primer is struck)--would all cause more problems than they would solve on a gun that has to be constantly reloaded on the run and make it through a full match without getting sticky and balky.

I guess I can see where a gentler forcing cone should be a good thing, other factors being equal. Once again, I'd like to see somebody find a way to test the free-bore thing empirically (no "true believers" or "cynical detractors" need apply).

Our .45 ACP wheelguns aren't all that accurate in general, compared to many other types of handguns at least. If real accuracy improvement could be made without causing some degree of countervailing functioning problems, or other detriment such as significant loss of velocity, etc., it would certainly be worth knowing about. But as silly as it sounds to say, if the freebore concept works so well, you would think all the handgun manufacturers would have figured it out and employed the idea long ago....

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Heck, most of them can't get the cylinders right, forget about getting fancy. S&W had it's huge model Model 25 throat sizes (I've seen them .456" or better) and they still routinely make the 629's on the snug side.

And of course, my favorite... Ruger (God bless em). 3-4 years of REALLY over sized 45 Colt throats, followed by 35 years of REALLY undersized 45 throats. You'd think after 50 years in the business, they'd know how to drill a hole the right size. :rolleyes:

I think Taylor throating is one of those oh so many things they don't HAVE to do, so they don't.

Edited by cas
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Manhurin used to make a specialised Bullseye revolver optimised for the .32 S&W with wadcutter ammo. It had a freebore section in the barrel longer than the length of the projectile. It was explained to me that they found it best to have the bullet supported in the freebore when the bullete hits the resistance of the rifling as the pressure on the base coupled with the sudden resistance of the rifling engaging the nose distorts a bullet that is bridging the gap between cylinder and barrel.

Makes sense to me. I wonder how revolvers can be as accurate as they are when the poor bullet has to make that great leap of faith across the cylinder throat, flash gap and forcing cone before receiving the proper guidance it deserves.

Peter Dawson

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Thinking about this some more, I think I figured out a problem with the freebore concept....

If the idea is to have a freebore (really, a smoothbore) section that is tight enough to actually stabilize/straighten the bullet before it is engraved by the rifling (Wil recommends the freebore be only .001" larger than the bullet diameter), the chambers would have to be perfectly aligned in order to introduce the bullets to the freebore. If the chambers aren't exactly dimensioned and perfectly located in the cylinder, if the gun goes even slightly out of time, or if the center pin hole or yoke barrel get a little loosey-goosey, the bullets would start slamming off the edges of the rear of the barrel. This would obviously defeat the whole goal of creating a gentle smooth entry into the rifling.

While it might be possible to create the ideal freebore on a specialized target revolver, or perhaps one of those custom big-bores made by Linebaugh or Bowen, it wouldn't seem practical on a production 625 to be used for run-and-gun competition shooting.

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the chambers would have to be perfectly aligned in order to introduce the bullets to the freebore. If the chambers aren't exactly dimensioned and perfectly located in the cylinder, if the gun goes even slightly out of time, or if the center pin hole or yoke barrel get a little loosey-goosey, the bullets would start slamming off the edges of the rear of the barrel.

That why there is still a forcing cone to guide the bullet into the "freebore". The bullet engages the rifleing after it's in the freebore instead of while it's in never-never land half way in the cylinder and half way in the barrel.

Edited by Tom E
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Thinking about this some more, I think I figured out a problem with the freebore concept....

If the idea is to have a freebore (really, a smoothbore) section that is tight enough to actually stabilize/straighten the bullet before it is engraved by the rifling (Wil recommends the freebore be only .001" larger than the bullet diameter), the chambers would have to be perfectly aligned in order to introduce the bullets to the freebore. If the chambers aren't exactly dimensioned and perfectly located in the cylinder, if the gun goes even slightly out of time, or if the center pin hole or yoke barrel get a little loosey-goosey, the bullets would start slamming off the edges of the rear of the barrel. This would obviously defeat the whole goal of creating a gentle smooth entry into the rifling.

I feel the concept of the Taylor throat works well after the wear in the parts you describe. The Taylor throat lengthens the free bore area allowing the bullet to stabilize after making the jump. I have noticed an increase in accuracy with the 627s I had (You saw them) after they were throated. I also used them for Center fire bulls eye so they got a good practical test.

As soon as I have the cash, I am buying a Taylor throat tool for the 45ACP to play with the 6" barrel on my 625. If it works Great, if it ruins the barrel, I have 2 more :blush:

Regards,

Edited by Round_Gun_Shooter
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But as silly as it sounds to say, if the freebore concept works so well, you would think all the handgun manufacturers would have figured it out and employed the idea long ago....

They figured it out, Mike, and they figured out that it would cost money, so they don't do it. There's tons of things that manufacturers could do to make any pistol more reliable, more accurate, etc., but they all affect the bottom line, and gun companies are in business to make money.

And who the hell is this Wil character, and what would he know about barrels?!?!?! Hell, I'll bet he probably tells people to not even clean their barrels...

Just Kidding, Wil!

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