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Old July 14, 2019, 05:26 PM   #26
HiBC
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Some folks use headspace gauges. Others are good at BS and using the workaround methods to make out of spec ammo for the out of spec rifles they gunhack together.

Its just not that hard to cut a chamber to length.


The word "datum" gets abused a lot.For most bolt guns we can call the plane defined by the forward face of the receiver ring a "datum" The shoulder of the barrel tightens against the face of the receiver ring. (I know,Savages with a locknut ,etc,are different)

Based on that idea,its not hard to depth mic from the receiver ring to the bolt face.

Its a lttle bit of a juggling act subject to feel and some error,but you can insert your "Go" gage into the short chamber and depth mic from the protruding end of the gauge to the barrel shoulder.

Make a little sketch,plug in the numbers and do the math and you have a very good idea of how "short" the short chamber is.

There are variations on how these measurements can be taken if you have a Travel-Dial or digital on your machine.

While I have confidence I could cut a chamber to spec with this method..I begin and end with the Gauge.

My BS alarm goes off big with hollow terms like "Transfer" and "verify" when they are not accompanied with detail.

"Varified" to what? If I were making that claim I'd be using inspected,calibrated gauges traceable to the National Bureau of Standards.

And "Yes" I have done that sort of work.

And I'd bet PTG,Elliot<Manson<Clymer,Forster,etc have the Master Gauges to verify their Gauges.

If you want to verify a chamber is closer than SAAMI spec, bracket the measurement with a custom gauge that's halfway between Go and No Go

A hard gauge is the Last Word.

I watched a vid on measuring chamber length once.The old hack cut a cartridge case in half and fixed a bore brush in one of the halve to provide friction with the other half. He'd crush the assembly into the chamber and assume he was transferring a chamber measurement.


Right.
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Old July 15, 2019, 07:19 AM   #27
Bart B.
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^^^^Good post!!!^^^^
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Old July 15, 2019, 10:23 AM   #28
F. Guffey
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Quote:
F. Guffey - care to start a thread on headspace w/out a gauge?
Thank you for the kind words.

We have members that can not measure the length of a chamber from the datum to the bolt face with a head space gage, we have members that believe they have to have 3 gages.

I have suggested the length of the chamber is not absolutely fixed, I helped a collector near Madison, Alabama with 18 Mausers. After he finished checking his chambers with gage I sent him, he found he had chamber lengths that went from go-gage length to +.024". He had 2 different 8mm57 chambers, I made him gages to check both chambers. The smiths in his area claimed they could not check his rifles because the test would require 2 different gages of three each.
And I have my doubts about finding someone on this forum that understands the 8mm57 chamber that was +.024" is longer than the a go-gage and .012" longer than a field reject length chamber.

I doubt the smiths in his area would be anymore fair and or objective with their criticism of my help. I also suggested he could load for the long chambers if he keep up with the length of the chambers. I also offered to form cases for 'some' of the long chambers if he furnished the numbers.

He turned the two rifle with the longest chamber into wall hangers. Case head protrusion could have been .134" on one of them.

I sent him a gage that was minimum length plus .024".

F. Guffey

Last edited by F. Guffey; July 15, 2019 at 11:06 AM.
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Old July 15, 2019, 07:10 PM   #29
HiBC
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Quote:
I sent him a gage that was minimum length plus .024".

How did you verify that? Specifics.
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Old July 16, 2019, 07:11 AM   #30
F. Guffey
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Quote:
How did you verify that? Specifics.
I sent him 20 gages: he was interested in loading for all of his rifles, in my opinion he was not getting help on the forum and he was getting less help on from local smiths.

The plan was for him to match his rifles to a gage, afterwards he could give me the numbers on the gage ; giving me the number would allow me to size cases to fit each rifle.

As to your question: I believe I would struggle to find where you have made any effort to find one find word from you and I do not have time to finish this because my wife says we have to go.

F. Guffey
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Old July 19, 2019, 03:06 AM   #31
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I went back and re=read the original post.
The question is about re-barreling and chambering a Savage Model 12,and whether a "No Go" gauge is absolutely necessary.

I have a couple of questions.I have not barreled a Savage.Is the Model 12 like other Savages in that the barrel can be rotated in the threads to contact a gauge and then a barrel nut locks the barrel in position?

Are you starting from a barrel blank or are you buying a pre-threaded chambered barrel? As you are talking reamer rental,I assume you intend to thread and chamber...and that can be good....but I suspect if the Model 12 Savage uses the lock nut system, some good barrel makers will sell you a threaded,finsh chambered barrel,already cut. You won't need to rent a reamer.

That money saved,....you can splurge and rent the No-Go just for the satisfaction of a good Go/Nogo check at the end of the job. You can get the barrel finish turned and polished,too.


It depends on what you are trying to achieve. I have no idea of your skill level.If this is a one time deal,and money is important....Your first thread and chamber job ,if you do not have an experienced mentor watching,has a fair amount of risk that the Murphy's Law character will show up. Things can go wrong .


Unless you really want the experience,I'd suggest you install a pre threaded,pre chambered barrel. Given that (I think) your Savage is "adjustable" with the barrel lock nut,buyng even a "short chambered" or "Long chambered" barrel to finish should not even be necessary. You can get one that just needs to be prpoperly installed (I think)


I could be wrong,Savage Experts please confirm or deny my suggestion.

Last edited by HiBC; July 19, 2019 at 03:15 AM.
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Old July 19, 2019, 12:20 PM   #32
Jim Watson
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I am not a Savage expert, but when a friend and I rebarreled our Savages, we just screwed the "prefit" barrel in to contact a Go gauge and tightened the nut. The guys who flip flop Savage barrels every weekend say that gives you about .0015" over Go as the nut takes up the slack in the barrel-receiver threads. It must have worked, the rifles are more accurate than stock and we see no signs of brass stretch.
I am sure you can make it a more complicated project, but I see no reason to.

Should I mention the practice of setting the barrel up on an actual cartridge or case?
Naw, let's don't, it would take a long thread to explain why that won't work, even though it does; especially if you have a case of brass of the same lot, enough to wear the barrel out.

Of course if you are working from a barrel blank, there are a lot more steps.
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Old July 21, 2019, 09:16 PM   #33
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HiBc
Its a prefit barrel, chambered, threaded, finished. I did a rebarrel on the same rifle a few years ago and have the tools. All I was interested in with the original post was go/no go gauge rental. I neglected to provide a better description of this project, namely buying a Criterion barrel. The thread took a life of its own.

Money wasn't a problem, and the feedback was good. I chose to set the headspace another way. It worked good. I probably would get flamed over my way of doing that, and I have no interest in justifying or defending how I did it. Results are in, and the rifle shoots great. The cases are suitable for neck sizing for the next loading. It has one abreviated prairie dog shoot to its credit, and another scheduled this coming week.

Last edited by Colorado Redneck; July 21, 2019 at 09:26 PM.
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Old July 28, 2019, 10:37 AM   #34
F. Guffey
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Quote:
Should I mention the practice of setting the barrel up on an actual cartridge or case?
Naw, let's don't, it would take a long thread to explain why that won't work, even though it does; especially if you have a case of brass of the same lot, enough to wear the barrel out.
Jim Watson, should you mention? You are preaching to the choir, Roy Dunlop said he preferred to purchase gages. He claimed he had friends that did not purchase gages and he said there was nothing suspect about their work. Today reloaders have their favorite/go to source for gages and no one can compare with their accuracy. I am not that vain,

I have confidence in my ability to measure the length of a chamber, length of the case from the shoulder to the case head. Again, I purchased a mill from a military recourse type on the M1, 03, 03A3, 1911 etc. He was having a difficult time determining the length of a chamber for a Rock Island 03 period correct 1911. He had 20 30/06 head space gages of different length. but nothing fit. He was on a forum that with a choir that wanted to pick them. And then as always they went after each other and left him with no way to measure the length of his chamber 'for clearance'.

I paid him for the mill, we loaded it and then I offered to help him; I gave him 4 choices. The easiest and most simple method indicated his chamber was .0075" longer than a minimum length/full length sized case or .0025" longer than a go-gage length chamber. It was then he decided he wanted the chamber to be go-gage length.

(Again) He had 100+ 03 type bolts, none of the bolts would reduce the length of the chamber .0025". I have 25+ 03 type replacement bolts, none of my bolts would reduce the length of his chamber.

I offered to size cases that would off set the .0025", he wanted the new owner to be able to purchase new, factory, over the counter ammo so that left him with finding a bolt that shortened the length of the chamber .0025".

The best advise he could manage from the Internet was the suggestion one member offered; purchases a bucket of bolts. And then I suggested if he knew out to measure a bolt and the supplier knew what he was doing he could get the correct bolt the first time.

I offered to measure the effect each bolt had on head space, all 100+, and then think about all the experience he would gain; he was not interested. He did contact another resource type. The other resource type sent him 5 more bolts.

F. Guffey
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Old July 28, 2019, 10:51 AM   #35
F. Guffey
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Money wasn't a problem, and the feedback was good. I chose to set the headspace another way. It worked good. I probably would get flamed over my way of doing that, and I have no interest in justifying or defending how I did it.
I have no problem measuring the length of a case from the shoulder to the case head, When I sit down to make a gage I make 20, that beats waking up in a new world every morning. Double the fun, the 30/06 and 8mm57 uses the same gage.

I went to visit the heart doctor, he lifted all restrictions. They went in to determine if I had any clots after they installed a pacemaker. after the pace maker they stopped the heart and then restarted it. He said the batter(y) may need changing; I asked if that was something they wanted me to do 'or'?

F. Guffey

Last edited by F. Guffey; July 28, 2019 at 02:20 PM. Reason: add y to battery
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Old July 28, 2019, 12:55 PM   #36
Bart B.
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2.0487 does not equal 1.8813. Nor does 19 equal 17.25.

Quote:
He said the batter may need changing; I asked if that was something they wanted me to do 'or'?
Did the batter not do well in the last several baseball games?
Or did the waffle maker run out of mix?

Last edited by Bart B.; July 28, 2019 at 02:01 PM. Reason: Couldn't pass this opportunity up!!!!
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Old July 28, 2019, 02:18 PM   #37
F. Guffey
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Quote:
He said the batter may need changing;
the ink on my key board for y is not getting low, I failed to hit it.

F. Guffey
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