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mikenbarb
April 19, 2008, 07:13 AM
I am looking to replace the barred on my Target rifle and have seen air gauged barrels for sale. Can anyone tell me what the difference is between air gauged and a regular target barrel. What does air gauged do and is there a big difference in accuracy versus a good quality barrel thats not air gauged?? Thanks in advance, Mike

SDC
April 19, 2008, 08:16 AM
Air gauging is just a way to measure to consistency or uniformity of a barrel; they pull or push a button-shaped plug through the barrel, and that plug has holes around its circumference that allow high-pressure air to be pumped through the plug; the rate of air flow lets you know how much space is around that plug, and therefore, how consistent the barrel is from one end to the other. They USED to do the same thing with a mechanical instrument called a "star gauge", and you can find 1903 Springfields that were passed through for National Matches with a little asterisk stamped onto the crown of the muzzle. Air gauging is really more of an advertising gimmick than anything else, but it can't HURT the performance of a barrel.

Scorch
April 19, 2008, 01:31 PM
Air gauging is just a way to measure to consistency or uniformity of a barrel; they pull or push a button-shaped plug through the barrel, and that plug has holes around its circumference that allow high-pressure air to be pumped through the plug; the rate of air flow lets you know how much space is around that plug, and therefore, how consistent the barrel is from one end to the other. Yes, you can measure bore consistency to .00005" very consistently (for the decimal-point-challenged among us, that is 1/2 of one ten-thousandth of an inch).
Air gauging is really more of an advertising gimmick than anything elseNo, really, it is a precision measuring tool capable of consistency of measuring bore diameter within .00005"! If you think that is a marketing gimmick, tell me another way to measure consistency of bore diameter and I will mock air-gauged barrels, as you seem to be doing. But the bore being consistent diameter is not everything, as you will find air-gauged barrels that don't shoot worth squat, and you will find barrels that were never checked that shoot fairly well. It also needs to be concentric, coaxial, and straight, and all that for under the price of a ham sandwich in order for some people to be interested.

SDC
April 19, 2008, 02:59 PM
Don't get me wrong; air gauging does let you measure a barrel to very close dimensions, as I said; but saying something is "air gauged" is not really any different than saying something is "tactical". There are people in the industry who would gladly sell "tactical coffee cups", and charge a 30% mark-up for the privelege of selling their velcro and Kevlar-clad masterpieces to plebes like me and thee. As a QC tool, "air gauging" is fine, just don't expect it to necessarily produce a rifle that shoots better than a non-air-gauged barrel.

James K
April 19, 2008, 08:04 PM
Hi, SDC and Scorch,

I think you both are saying the same thing. Air gauging (like star gauging) tests for uniformity of the barrel diameter, but neither guarantees that the gun on which the barrel is installed will shoot better or even as well as a similar gun with a barrel that has not been tested.

It was fairly common in the "old days" to hear someone complain that he bought a "star gauged" M1903 and it didn't shoot. Same thing today.

(I might also point out that simply saying the barrel has been air gauged is meaningless without also saying what the results were.)

Jim

Martyn4802
April 20, 2008, 06:00 AM
Saying a barrel is air gaged is nothing more tham me saying that I measured the barrel inside. The question is, what were the restults of the measurement? Just because it was measured by air gaging doesn't mean that the measurements were any good, for accuracy. If the results were that the barrel did in fact measure to within .00005 accuarcy, land to land, and groove to groove, from chamber to muzzle, then it is a very good barrel.
Saying a barrel is air gaged is marketing nonsense if results aren't provided for the measurements.

Martyn

Harry Bonar
April 20, 2008, 04:27 PM
Sir,
I,ve been in the Douglas plant many many times and know the men,
Their barrels are air guaged several times during operations. The air guageing gives you a uniform measure of the bore or groove diameter. The final air guaging is done afer the stress relieving heat and this determines the final bore or groove diameter.
Of course it gives you the measurement. Like for 30=06 it will be .308 maybe with a taper towads the muzzle of .0005 or .0002 and the breech and muzzle will e so marked it is extremely accurate.
Yes, it does give you the correct dimension.
Harry B.
1 304 776 1341 Douglas Barrels.

mikenbarb
April 20, 2008, 07:33 PM
Next question, What is a good barrel for a swede 96 Husqvarna in .308? Also I am possibly looking into a cryo barrel. Is cryogenic treating really all what its said to be or is it just a gimmic? And if its a good thing, Would I be able to cryo treat a barrel myself??? I have access to all gasses in liquid and vapor state including liquid nitrogen, Liquid CO2 and dry ice. If I try to cryo a barrel myself are there any risks of barrel failure(blowing up)by me freezing a barrel and letting it slowly graduate up to room temp. :confused:

HammerBite
April 20, 2008, 08:37 PM
One rifle maker's opinion of cryo (http://www.shilen.com/faq.html#question1).

Scorch
April 20, 2008, 11:54 PM
"tactical coffee cups":p Oooooooh, oooooh, I want one!!! Can I get it in digital camo or just on black? Tactical: what a load of "marketing".

Yes, just saying a barrel is air gauged means nothing unless they also tell you how close to true the bore is.

Martyn4802
April 21, 2008, 05:05 AM
Scorch said: "Yes, just saying a barrel is air gauged means nothing unless they also tell you how close to true the bore is."

Exactly.

Martyn

mikenbarb
April 21, 2008, 09:13 AM
Thanks everyone. Does anyone know of a good barrel company that offers good quality .308 barrels for around $400.00 ? Im mostly a shotgun guy but am getting more into long range shooting. The gun I have has a Kimber barrel on a Swede action and shoots well to 300 yds. but im looking to get out further with better accuracy. And do any barrel makers offer a guaranteed accuracy? Sorry for all the questions but im not too familiar with aftermarket rifle barrels and the quality of them. Thanks in advance, Mike

Scorch
April 21, 2008, 01:46 PM
For $400 you could have your choice of many high-quality barrel blanks and have it installed. In my order of preference, given the price range: PacNor, Hart, Shilen, Douglas, ER Shaw. There are other barrel makers who make great barrels, some more expensive, some about the same, but these are the ones fit into your budget and that I have experience with or personally know someone who has one.

Some barrel makers offer accuracy guarantees, but typically only if they do the work, and onlyin certain actions with certain ammunition. But any of the barrels mentioned will be a very high quality barrel, capable of outstanding accuracy.

Something to consider, given the age of weapon you currently own: consider buying a newer rifle such as a Remington or a Ruger in the caliber you want. The newer rifle will be much more rigid and capable of better accuracy, while still retaining the eye appeal you seem to enjoy in your 96 Mauser.

Harry Bonar
April 21, 2008, 02:45 PM
Sir,
All barrels are air guaged, Cryo relief, is just another way of stress relieving, Yes you will get a 30 cal bbl with correct dimensions if you order one, No, stress relief, air guaging, cryo or anything else is not sales talk, Yes barrel makers, good ones, will label a barrel either muzzle or breech.
Everybody is not a crook. I trust the major barrel makers to give you a good accurate barrel.
However, the best barrels were made by old men, on hand made appliances by eye and they shot better than any cryoed barrel made and with primitive rests and sights.
Start relying on gimmics and just order a Douglas barrel.
Harry B.

krs
April 27, 2008, 06:27 PM
mikenbarb,
I think what Scorch was saying may be more important than you realize.

A fine barrel will not by itself give you an accurate rifle. A rifle is made up of components and the alignment of each to the others is a critical element of an accurate rifle. This means that there must be an exact matching of the receiver to the barrel at their joint so that a line drawn through the bore from the precise center of the bore will exit the assembled parts at the exact center of the receiver. The chamber has to also be on this same line from back to front. Concentricy means that all elements revolve, or could revolve around the single line through them all within a variation of less than .0002" of an inch. Some say .0001" is better and there's no reason to dispute them.

The receiver and bolt needs to be so rigid that no fluctuation of their dimensions can occur even under the pressure and shock or temperature variations of firing the rifle.

This needs good parts and skilled assembly to complete. Once you have a satisfactory barrel and receiver chambered in your choice of caliber the subject of stocks and sighting equipment can enter this fray.

Caliber too is a variable, as some shoot better than others.

So simply seeking out the best barrel and having it installed will not necessarily give you the result you hope for, air guaged or not, cyrotreated or not. There aren't any easy answers.

mikenbarb
April 28, 2008, 07:06 AM
I ordered a Douglas barrel yesterday for the Swede. I have two of these same rifles now but the one shoots a tiny bit better than the other. The new barrel is going to go on the lesser of the two that im going to keep for the range. I will let you all know how it shoots after my gunsmith finishes it. Im also thinking of having the bolt polished and some trigger work done. Does anyone know what else I can do to a Swedish 96 Husqvarna action to improve accuracy? Im looking to stay around $250.00 for the barrel install and action improvments. Thanks, Mike