Seems to me it needs a much stronger spring. I am sure I am not the first person who thought that. Can I replace the spring? I have not looked at it to see if it's possiable?

It is quite tricky to use, but I have found that being careful, one can get consistent results. The better ones I have seen have been (much) more expensive.

I'm not sure how the spring is done, but all these dial gauges have light springs - I suspect because they are a light (delicate) mechanism.

If you are talking about the Manson type gage, there is no spring. If used like shown in the horizontal position, the weight of the barrel holds it on the ball bearing for getting a reading. Also if the gage is in a vise and you slide the barrels and read the gage, there is a good chance that you will deflect the bar and get an inaccurate reading.
If you use the gage vertical, then you need a spring opposite the ball to hold the barrel tight against the ball as you slide the barrel over it.
I made a Manson type gage to be used vertical. I hung it from a rafter, the trouble is you need two people, one to write your numbers down, or else you have to slide the barrels off and then write the numbers. I mark the barrels in 4" increments and read the whole length from bottom rib to top rib, so there are quite a few readings.

The one that more seem to be using is the Hosford gage, it is similar to the Manson gage, except the bar is clamped on a table, the barrel is placed upon it and you then slide the gage over the rod taking readings while your other hand is rotating the barrel. You hold this gage by using the ring on the back end and putting your finger through it. Once the barrel is on the gage, you zero the indicator and glide it over the rod and read the thickness. This gage is $500.00 and you can use it from .410 to 10 gauge.
The other one that is used is the Galazan gage. It is used vertically, but on a table. It has two rods, one for 20-16 ga. and the other for 12-10 ga. You can read the whole barrel from top rib to bottom rib. The top of the rod/s have a ball bearing and on the opposite side have a spring that holds the barrel against the ball. This gage cost about $450.00.

I made one like the Galazsn gage, it is good for home and not for shows as it is heavy. I'm not sure that the Hosford one is show-able also, as you would have to clamp it to someone's table. Not sure how they would like that.

I have posted pictures before, but I will post another.

Monty, after many years of experimentation and use of the Manson gauge in all positions and with and without the Gaddy modification, I now only use the gauge in the horizontal position with the barrels held in a vise or by a helper. The other poster is right about clamping the gauge in a vise. It doesn't work. You clamp the barrels, support the gauge end with a short rope loop and zero the gauge while holding the the ball between the thumb and index finger of the other hand. Then insert the ball in the barrel and take your readings. Rotate the barrels for readings on 90 degree surfaces and on the other barrel. This method was taught to me by the master, Mr. Jon Hosford. Sorry for the edit. I think I got it right this time.

Eightbore, why is the manson gauge in the horizantal position superior to hanging it vertically ?

At this juncture I have yet to get an accurate measurement from the manson gage. I am both rocking the rods, though they seem to rock less when held in the vertical and getting the rod off center where I'm perpendicular to the surface and getting sidewall readings. Are there any videos on how to use this infernal thing?

Colonel, I never thought to ask Jon that question. He showed me how to do it and I've been using his method ever since. By the way, I edited my post to explain the correct way to zero.

Thank you for the follow-up. While the Manson Gauge is not the greatest it beats having nothing at all.

The look of the Cabela's gun library staff when I show up with my Manson gauge, bore light, chamber gauge et al is classic. While they do not describe their guns as well as they could over time I have to admit they are at least cooperative in working with me.

Youtube on how to use the Hosford gage. Part one and two.
http://www.youtube.com/watch?v=1jQZn4kohH4

In using the gage to measure breech you need to lay it on a table and have someone hold and rotate barrel or else do it the way he does. In my opinion, not a user friendly way and again, my opinion, the most critical area we want to see wall thickness readings.

I'm still a believer in measuring the ID and OD of barrel to get wall thickness. The short coming of that method is the outside edge of the barrel where it is most likely to have been re struck to polish out a dent, is the area most likely to be thin and it can't not be read using the OD/ID measurement. For that measurement that I wish I had a thickness gauge. But as I've said before, the manson gauge remains beyond my understanding and capabilities.

Just for clarification, the Brownells gauge (I have) is a Manson. I think the spring the original post refers to is the spring loading of the plunger in the dial gauge. This is the only spring present and is very light. It is built into the dial gauge and cannot be strengthened as it works through the light precision mechanism of the dial gauge.

The Brownells/Manson gauge is as I said above quite tricky to use, but with care I'm able to get consistent results and it is very much cheaper than some of the more satisfactory offerings I have seen (which are often many times the price).

I've seen the Manson gunge modified by putting a leaf spring on the bottom bar. The spring rubs against the opposite wall to make point opposite the gage follow the wall more closely. Anybody here have experience with that modification?

pooch, this is my original rendition of the Mason gage that I made. This is the modification that eightbore stated that Dr. Gaddy used.



This is also not a friendly gage to use as you need someone to write your figures down, as I copy all my readings of the ones I measure.

As to the spring tension on the dial indicator, why would you need more tension on the needle?

I just spent an hour and three beers trying to come up with the precise reading.I could not come up with a reading that I would want to be the expert witness in a court of law.I did clamp the barrel to a table and put some Styrofoam behind the ball to keep it closer to the inside the barrel but I am not sure that worked any better than nothing.. I am going to try foam rubber next.I am sure of one thing RookHawk is right my W.C.Scott measured about .045 to .050 thickness 9 inches from the breech which makes me think it needs to at least be that thick 9 inches from the breech buy this was a 13 bore.

Jewler and Pooch,
Have faith! I too purchased a Manson wall thickness gauge from Brownells and mounted it to a wall and immediately figured out that there was no way to get accurate, repeatable readings and thought gee, that was a waste of $100.00!
After much research, I have discovered that the way to use it is exactly as Eightbore described. Use it just like the Hosford gauge.
Watch the Hosford video to get an idea about what we're talking about. Then thread a piece of rope or webbing through the hole in the centre of the gauge. Zero the unit by holding the rope (so you do not influence the reading)and the sides of the ball. Slide it into the barrels and read away! Make sure that the ball is the only part touching the inside of the bore otherwise you will get a false reading. It is easy enough to get the hang of provided you can keep the barrels in place. I suggest putting the barrels on a bench and anchor them down with a couple of bags of shot. Pre load the plunger with .200" (as I recall) as per the instructions.
I can get accurate, repeatable readings with this method and I think it is useless if fixed in a vertical position.
Gravity does the work of keeping the ball in contact with the inside of the bores and the plunger is not affected as it is on the opposite side.

I think I got it.YOu had me lost with the loop on the rope but I see what you mean now.I still might do what 8 bore did and have a leaf spring put on the back of the ball.

Thanks Blue Grouse and 8 bore only problem now is that when I measure the W.C Scott these tubes are less than .020 but theis is about 9 inches from the muzzel it is .045 9 inches from the breech. Hummmm

The Galazan vertical gauge is the one to buy. There is no question on its accuracy. Too heavy to take to shows? EZ solution, you keep it in the car, leave driver's license or something else of value with vendor that owns the gun, and take the barrels only out to the car and measure them. Unless you're an inveterate tire kicker, how many guns are you going to measure at a show? Or mayhaps you like to impress people that you're smart enough to own a wall gauge and like to show off your portable one? Much ado is made of walking gun show rows with portable wall gauge but try it some time. It's a hassle to carry around and when you rest it on adjacent table to pick up a gun the vendor there complains that you're taking up his table space and you might scratch his guns on display. Or try walking with the gauge in one hand and a bag of goodies you bought in the other. Portability of these tuning fork type gauges is good in theory only. Just get the Galazan and forget about writing up long tomes to convince others that your portable gauge is accurate and repeatable and is so, so very EZ to use at shows.

Dog fox I agree with everything you are saying but am cheap.After doing what 8 bore and blue grouse said it seems to more consistant and if I put a leaf spring on the back I think it would help it more.

Blue Grouse has figured out and explained my method exactly. By the way, I do NOT use the Gaddy spring. It is not needed when you use my and Blue Grouse's method. As Blue Grouse explains, gravity is sufficient. Good luck.

Amen to the Galazan gauge, that's what you need for quick accuracy.

Incidentally, Monty, when you started rattling off prices in which you'd buy or sell guns and you lacked a proper gauge, I was thinking you were destined to be burned or burn someone else (no malice intended). It sucks to drop $1000 on tools but before I ever bought a vintage gun (and especially before I sold one I didn't want any longer) I made sure I had all my tools.

Buy:

A skeets universal bore gauge $200
A galazan wall gauge $550
A full turnscrew set $200
A chamber gauge $35

Every time I get a gun I blueprint every inch of the barrels and determine whether it is in proof and whether it as been reproofed. It tells volumes on the life of the gun.

Rookhawk has the right attitude, except that the Manson gauge will do everything the Galazan gauge will do for $450 less, and proof is bullshit.

Rook Hawk I couldn't agree with you more but as I said I am cheap. I own a bore gauge I think I paid $100 a few years back and the brownells I think I paid $100 for the fun. Being inexperienced as I am I usually rely on other people who have had the experience meaning expert gunsmiths.Which to me is more valuable than the tools.If you are not a gunsmith and most of these guys probably not be qualified to me to be an expert or give what I would call an expert opinion.But as I said I value every opinion out there yours included.I can assure you I don't care how many tools you have you cannot measure exsperience.
By the way I have sold several guns on this site I will give them two weeks to decide or take it to a gunsmith if they don't like it I'll give a full refund even if they can't find anything wrong.
I talked to Curt Marrington again today and he said he has had guns that measured .010 thickness near the muzzel end to proof.
Kirk said the problem is with dents.

RookHawk I am with you I might pass if the Holland is only .025 near the forcing cone.I'll get Curt to look at it first.

Recently bought a Manson gauge, to measure wall thickness in a 20 gauge Birmingham boxlock. In order to have some assurance that I'm using it correctly, and getting accurate results, I intend to practice on a junked barrel the local gun shop owner was kind enough to give me. My plan is to take measurements in the horizontal position. and then cut the junk barrel with a Metabo cut off tool, either wedges cut out opposite each measuring point, or a strip cut out along the whole length of the barrel, thereby gaining access for a machinist friend to use his micrometer to take direct measurements. And then compare those with the measurements I got with the Manson gauge. Anyone have any ideas on how to improve on this procedure?

"And then compare those with the measurements I got with the Manson gauge. Anyone have any ideas on how to improve on this procedure?"

When I take wall thickness readings, I take them in 4" increments along the barrel. The Galazan type I made is a copy of one a friend has. I can measure close to 16" and then flip the barrels end for end and read the other length providing the chokes are not too full in a 12 gauge. Meaning if the muzzle end is .690 I cannot fit it over the rod. Once it is centered on the bottom brass cone, I pivot the barrel on the brass cone that is locked on the shaft from top rib to bottom rib and read the wall thickness and record the readings from lowest to highest. I then move the brass cone down another 4" and do the same until I get to where I left off from the other half.
Most of the time, the readings vary as the barrels are not concentric as most are not.

Beagle, that is a good way to prove that you are using your Manson Gage right, but you have to read the barrels as I stated and write down the areas where the readings were taken to compare them to the micrometer readings. In order to measure them with a micrometer, you will have to use a ball micrometer, or better yet a pin one to get accurate readings as a flat anvil micrometer will not give you accurate readings.

Please let us know what your results were. Also if these barrels have pitting in areas, measure some of the pits to see how deep they go.

Beagle
That sounds like a good Idea to me although my micrometer is flat not a ball but that can't be too far off I'll have to try that on the muzzel end to see.I am going to get someone to put a leaf spring on the back of mine to hold it snug against the barrel.

You can purchase a ball attachment for an ordinary flat anvil micrometer. Pretty sure the one I have has a diameter of .200" & has a collar to center it over the anvil. You can simply run the spindle down against it to verify the reading. Measure a few bbls at points you can each with the micrometer & then with the wall thickness gauge to confirm. If its accurate at one point, then as long as you make certain you don't lket the shaft of the WT gage hit the side of the bbl it will be accurate at any point. This same caveat applies equally even if you cut up a bbl. There is however no real need to go to the trouble of cutting up a bbl, even a useless one, to prove it. You are of course goint to need either the ball mic or attachment either way so nothing extra required.

Monty, "That sounds like a good Idea to me although my micrometer is flat not a ball but that can't be too far off..."

Yes it will, your flat anvil will only be touching two sides and not letting it get to the bottom. It could be as much as .015 or more.

Thanks for the advice on micrometers. This is a new area for me, I was not even aware there were different types of micrometer. I will post the results when the project is complete.

How do you used the manson horizontally? I can see how it might work vertically but it would seem moving the instrument horizontally would cause it to tilt. More instructions and more detail please.

I have the brownells gauge and it seems to work just fine for me. I use it horizontally.
I zero the dial by supporting the bar just behind the ball with my finger and then holding the connecting block with my other hand. If you support the bar farther away from the ball, the dial will move.

I clamp the barrels in my padded stock makers vise and then slide the guage down the barrels making sure to keep the bar centered in the bore ( or at least not touching in the open end). That way, the contact of the ball on the bore is just like me supporting it when zeroing it.
This way of measuring only works on the bottom side of the barrel you are measuring, so changing the position of the barrel is required often. My padded vise allows for the barrels to be clamped in almost any orientation.
I usually measure the tips, bottoms and sides of the tubes. But measurements In between these points can be taken as well if I think needed.

Basically this method of use is very similar to the demo of hosford's tool.

Thanks for your explanation, Mr. Dudley. I have explained this method a dozen times and readers insist on ignoring it, even though it comes directly from Jon Hosford. At least two of us can get some use out of the Manson gauge. It is amazing that Pooch can read this entire thread and still insist that he can't figure out how to use the gauge horizontally. Of course, I have only explained it a few times in this thread.

Mr. Dudley and Eightbore, your description of operation is quite accurate. One thing I use to hold the barrels in a horizontal position on the workbench is a partially full bag of shot, laid over the barrels. The bag of shot seems to hold the barrels well in any rotation position.

I don't have it yet but I recently won a Clymer Barrel wall gauge on the NOTSSMBBS Christmas charity raffle. I'm excited and looking forward to measuring everything in the county with it. Any tips for a novice operator?

The Clymer gauge should be identical to the Manson gauge. Manson and Clymer worked together and both put their name on the simple tuning fork style gauge.

When you learn snap me in Bob. I'm still wrestling with why you would hang the gauge by a cord then use it horizontally.

pooch, if you hang it vertically that you need spring tension opposite the ball to keep the barrel against the ball as you are reading it. The one advantage of doing it vertically is that you can read from bottom rib to top rib easily by just rotating the barrel. The hard part is you need someone to write the numbers down or else you have to take the barrels off the gage and write down the numbers.
Again this is my opinion, using the Manson, Clymer gage in the horizontal position and holding the barrels down and sliding the gage into them, is that you can only take a partial reading and then have to move the barrels maybe a few more times to get complete readings from bottom rib to top rib. There is only so much you can move the gage before the weight of the bar is not making good contact with the ball bearing on the barrel.

The Galazan gage is a lot easier to use. The hardest thing about making it is milling the area for the spring. It is a tapered slot that when the tapered brass piece is in place and compressed, it is the same size as the shaft (5/8") plus the ball bearing that is drilled into it. I believe the ball bearing I used was 3/16", so less than 3/32" is sticking out.

When you take a horizontal reading, do you have the micrometer gage on the top of the barrel or on the bottom with the dial hanging down? Thanks

in order to get a reading, the indicator would be below the barrel so that the weight of the bar would keep the ball bearing on the barrel.

Instead of putting the gauge down to write measurements just use Siri. I really just want to know the thinnest point and where it is in relationship to my hand position.

I briefly looked over the instuctions that came with the Brownells gauge and it seemed to be too much messing around when I could just use it horizontally without mounting it to anything.

I also think that when using the gauge vertically there is too much of a chance of applying pressure to the ball, causing an innaccurate reading. Any bit of movement on that will effect the reading by quite a lot.

Daryl,
Your bag of shot method sounds like a good solution for holding the barrels if one does not have a good vise to do the job.

My stock makers (or pattern makers) vise is great for this since both jaws are padded and they rotate independant of each other. Making the secure and safe holding of nearly any item easy.

The only micrometers my friend has are the flat anvil type, but he does have a Starrett electronic caliper. The contact edge of the caliper arms is nearly a knife edge, so I think will give an accurate reading even on a curved surface. So, on to plan B. After taking measurements at marked points on the junk barrel, cut it into segments, cutting just ahead of of the points measured with the Manson gauge. Then, after deburring, measure with the calipers and compare readings.
Don't know how I got so deep into the technical end of shotguns. Deep meaning over my head. All I wanted was a lightweight 20 to take woodcock hunting.

When you use it horizontally do you hold it in your hand or suspend it with a looped cord?

pooch, did you read any of the other posts?????????

Yes I read them all! It seems the less a person knows the more parsimonious they are about sharing what they do know. It's a simple question that begs a simple answer.

Pooch, depending on the horizontal measuring device, if it has a built in loop, you can just stick your finger through the hole. A loop of cord through such an opening is even better in that no torque can be transmitted from the cord to the measuring device. The first method is fine, though.

I understand that some Manson gauges have loops, but mine required that I install a loop. Daryl is right, the rope is more convenient.

Thanks gang! Now let's see if I can put all this good information to a good use.