PDA

View Full Version : 03 How to mount barrel with no witness mark?



Sgt USMC
03-31-2020, 01:05
I have a 03 Springfield that was stolen and recovered by a fisherman who found it in a stream, in Montana. It was then returned to the original owner by the local Sheriff's office. The original owner's friend ,"cleaned it up" and in so doing eliminated the witness mark. I bought it at a local gun show for $25.00 and was going to turn it into a lamp. On one of my trips out of state I took it to a gunsmith friend, who built weapons for the Marine Corps museum. He said to rebuild it and supplied me with all new parts. My gunsmith passed away a few years ago and I'd like to put this together as kind of a tribute for all the time he spent teaching a poor young Lcpl how to fix broken weapons. That being said I've searched a few forums and have some ideas, but I wanted to see what the experts here have to say, about mounting a barrel that does not have a witness mark on the receiver.

My second question is ; Does anyone have the a diagram with dimensions for where a Hatcher hole should be machined?

This weapon as been drilled and tapped for a Lyman peep sight and has no collector value other then the story that came with it.

Thank you for your time and knowledge, Semper Fi!

lyman
03-31-2020, 01:58
you can use the extractor cut,

using a barrel vice, and receiver wrench tighten it up, and insert a bolt with extractor to see if it clears,

maybe use a feeler or a piece of tape or 2 on the top and bottom of the lug to make sure it is centered

fguffey
03-31-2020, 03:57
That being said I've searched a few forums and have some ideas, but I wanted to see what the experts here have to say, about mounting a barrel that does not have a witness mark on the receiver.

Do you have a receiver with no barrel? Do you have a barreled receiver with a mark on the barrel and no mark on the receiver? Does your old barrel have sights? Does your new barrel have sights? Do you have an extractor cut on your old barrel? Do you have an extractor cut on your new barrel?

F. Guffey

John Beard
03-31-2020, 09:47
As lyman pointed out, you can use the extractor cut for indexing in lieu of a witness mark. If the barrel is good and tight and the bolt with extractor will fit, then you're good to go. Unlike an M'03-A3, the M1903 rear sight is mounted on the barrel. So the front and rear sights will align regardless of receiver indexing.

Good Luck!

J.B.

fguffey
04-02-2020, 09:10
As lyman pointed out, you can use the extractor cut for indexing in lieu of a witness mark. If the barrel is good and tight and the bolt with extractor will fit, then you're good to go. Unlike an M'03-A3, the M1903 rear sight is mounted on the barrel. So the front and rear sights will align regardless of receiver indexing.

If aligning the witness marks/extractor cut was all there was to it then you have a do it yourself project. Life has not been fair to me because all of my rifles have chambers. I do not care where all of those marks align I have to determine the length of the chamber. With 03 variants I have found chambers that were short and the barrel mark passed the receiver mark. On others I have I have had barrel marks not make it to the receiver mark.

That is the part of life that is not fair but if you are lucky the chamber will be go-gage length and THE MARKS WILL ALIGN; and you did not learn anything.

F. Guffey

lyman
04-02-2020, 09:58
If aligning the witness marks/extractor cut was all there was to it then you have a do it yourself project. Life has not been fair to me because all of my rifles have chambers. I do not care where all of those marks align I have to determine the length of the chamber. With 03 variants I have found chambers that were short and the barrel mark passed the receiver mark. On others I have I have had barrel marks not make it to the receiver mark.

That is the part of life that is not fair but if you are lucky the chamber will be go-gage length and THE MARKS WILL ALIGN; and you did not learn anything.

F. Guffey

I think you are overthinking the original question,

fguffey
04-02-2020, 11:38
I do not care where all of those marks align I have to determine the length of the chamber.



I think you are overthinking the original question,

I do not want anyone to think I am desperate for attention but the op is a Sgt USMC, If there is something I said he did not understand he can ask for help. I could start asking you what you think but to be honest I do not care.

I understand I wasted my time explaining how much trouble a member of this forum had trying to find information, methods and techniques on measuring the length of the chamber from the shoulder to the bolt face. There is no other way for me to explain I have three different methods and none of them include a head space gage. The man had 20+ head space gage, he handed me the box, I told him there was not a gage in the box that would indicate the length of the chamber from the shoulder to the bolt face in thousandths.

I did offer to modify one of his go gages to a 'go to infinity gage', all he had to do was shorten the length of the chamber .0025" to get the chamber down to go-gage length. I offered to size cases by increasing the length of the case from the shoulder to the case head .0025 but he wanted a go-gage length chamber. That is when I offered to measure the ability of his bolts to off set the length of the chamber, he had 100+. I promised him he did not have a bolt that would change/shorten the length of the chamber .0025".

Again, I am not interested in what you think, I am interested in what the OP thinks. And then there is that thing about me and Marines, it all started in 1954, a story you do not have time for.

F. Guffey






Sgt USMC is offline

lyman
04-02-2020, 02:45
I do not want anyone to think I am desperate for attention but the op is a Sgt USMC, If there is something I said he did not understand he can ask for help. I could start asking you what you think but to be honest I do not care.

I understand I wasted my time explaining how much trouble a member of this forum had trying to find information, methods and techniques on measuring the length of the chamber from the shoulder to the bolt face. There is no other way for me to explain I have three different methods and none of them include a head space gage. The man had 20+ head space gage, he handed me the box, I told him there was not a gage in the box that would indicate the length of the chamber from the shoulder to the bolt face in thousandths.

I did offer to modify one of his go gages to a 'go to infinity gage', all he had to do was shorten the length of the chamber .0025" to get the chamber down to go-gage length. I offered to size cases by increasing the length of the case from the shoulder to the case head .0025 but he wanted a go-gage length chamber. That is when I offered to measure the ability of his bolts to off set the length of the chamber, he had 100+. I promised him he did not have a bolt that would change/shorten the length of the chamber .0025".

Again, I am not interested in what you think, I am interested in what the OP thinks. And then there is that thing about me and Marines, it all started in 1954, a story you do not have time for.

F. Guffey






Sgt USMC is offline

I stand by my comment,


have a great night Guffey

gjungle56
04-02-2020, 03:17
If a 1903 barrel with rear sight on, simply screw barrel on until the rear sight base, with ladder off or aside, is parallel with receiver bottom. If no rear sight, I align to front sight or it's key much like a Garand. Do not tighten using rear sight base as a point to wrench from. Hatcher holes vary a bit but ones I've put in are 1.000" from receiver face, .690 up from receiver flat and 7/32 dia. A carbide end mill works very well in a mill. For what it's worth, I never trust witness marks.

Sgt USMC
04-02-2020, 05:43
Thank you everyone for your responses! Since the receiver was already drilled for a Lyman peep sight, I didn't see any reason to machine the barrel for the rear sight base of the 03. The barrel is a new, in the cosmoline, 03A3 SA dated 8-44 (old DCM stock) The new barrel has the front sight post. I have all new internals the only original part I will be using is the receiver. As I stated it does not have a witness mark on the receiver. It will be an 03 receiver with all A3 parts. S/N 852xxx
47323 Originally I was going to machine a "T", that would fit the front sight post. I would use a spirit level on the "T" and on the receiver rails and a plumb bob to check my work. But I thought their might be a better way hence the reason for my post.

In regards to the Hatcher hole; What I wasn't sure of is, did they originally drill from the #30 hole on the right side through to the left side, as a pilot hole and then enlarged it from there

Thank you again for your responses, it is much appreciated!!

John Beard
04-02-2020, 07:16
If your barrel has no rear sight base and you plan to use a Lyman receiver sight, then you have an alignment challenge. Unless the front sight is aligned directly above the top center of the receiver, you may have a large windage offset in the Lyman sight. As I recall, the extractor cut in the barrel is a little wider than necessary to accommodate tolerance stackup. So you can't use that reference for tightening the barrel. You, therefore, need to observe carefully when tightening the barrel to align the front sight with the top center of the receiver.

Good Luck! And stay safe!

J.B.

lyman
04-02-2020, 07:36
interesting,

when I read your post I thought you were mounting a 03 barrel to an 03 receiver,

in that case, you can clamp a flat bar to the front of the barrel near the sight, and make sure it is perpendicular to the post,

and then install your rear, and mount a level to the arm the aperture is mounted to,



or just do a trial and error

fguffey
04-04-2020, 10:47
SGT USMC, I will tell you I am not the expert but if I was involved I would screw the barrel into the receiver first. After screwing the barrel into the receiver I would check the alignment; in the perfect world the shoulder at the end of the threads will seat against the receiver with the extractor cut aligned.

And then it is time to think about it; I would strip the bolt, back the barrel out and then chamber a minimum length/full length sized case. After closing the bolt I would screw the barrel in until the shoulder at the end of the threads contacted the receiver or until the shoulder of the chamber contacts the shoulder of the case.

Because I am not the expert I would not start this job without a feeler gage nor would I start with a case that is minimum length/full length sized. Because? The threads on the barrel and receiver are 10 per inch keeping up is easy.

And then there is the length of the chamber from the shoulder of the chamber to the bolt face. Because I am not the expert this stuff does not drive me to the curb. In the perfect world the go-gage length chamber will be .005" longer than a minimum length/full length sized case; meaning I want to know the length of the chamber from the shoulder of the chamber to the bolt face, If the bolt closes on a minimum length/full length sized case you will not know the length of the chamber.

F. Guffey

fguffey
04-05-2020, 11:53
meaning I want to know the length of the chamber from the shoulder of the chamber to the bolt face, If the bolt closes on a minimum length/full length sized case you not know the length of the chamber.

This does not mean I do not know nor is it implied I can not measure, I would not waste my time asking the experts.

F. Guffey

lyman
04-05-2020, 02:43
you know most folks would install, check headspace, ream if needed , and go shoot,,,

fguffey
04-06-2020, 10:23
check headspace, ?

I am not most folks, I am the folk that wants to know the length of the chamber, I want to know 'the clearance'. I am the folk that knows the bolt can close on a go-gage even when the chamber is field reject length. I understand that means nothing to most folks.

I am the folk that would form 280 Remington cases into 30/06 chamber; the reloader that can do that can determine the length of the chamber even when it is .050" too long from the shoulder to the bolt face.

Again; I have a 30/06 chamber that is .016" longer than a go-gage length chamber, "THEY" do not make a gage for my chamber but even that does not slow me down.

F. Guffey

- - - Updated - - -

And the other folk that could 'do it' was Elmer Keith.

F. Guffey

gjungle56
04-08-2020, 05:06
Still trying to figure out why this is so complicated to some. Tighten barrel in to your preferred alignment. Mine in this example is the front sight key in the true vertical position. Then check, with component bolt, and ream headspace, if needed, to between go and no go. If you want an exact number I believe there may be gages made in .001 increments. My poor man's way is 7/16 dia shims to put on top of gages, between bolt and gage, to tell you your exact headspace. I still can't figure what this "chamber length" is, and measuring with cases? Is it headspace? If it is, call it headspace and measure with gages. A tip for those who wish to close headspace a bit, try a Browne &Sharpe bolt, I have found them to be about .002/.003 "long".

fguffey
04-08-2020, 08:57
A tip for those who wish to close headspace a bit, try a Browne &Sharpe bolt, I have found them to be about .002/.003 "long".

I have 4 B&S bolts, they came two to the box, logic says the two bolts in the box would not be identical; there is not .001" difference on all 4 of my B&S bolts, and then it gets better. I have 25 Remington replacement bolts + the B&S bolts, there is not .001" difference in all of the bolts when it comes to changing the length of the chamber from the shoulder/datum to the bolt face.

It is not complicated unless you are trying to repeat what you have been told to say. The first A3 rifle I checked was unique. It only took me seconds to determine the difference in length between the chamber and the case because of the design.

F. Guffey

- - - Updated - - -



A tip for those who wish to close headspace a bit, try a Browne &Sharpe bolt, I have found them to be about .002/.003 "long".

I do not know of anyone that wanted to increase the length of the chamber, and I understand I would be wasting our time if I tried to explain why.

F. Guffey

gjungle56
04-08-2020, 09:25
B&S bolts are longer lock lug to breech face. They lessen headspace.

fguffey
04-08-2020, 09:53
B&S bolts are longer lock lug to breech face. They lessen headspace.


If that is true I should feel cheated. I am one of the few that has gotten up and walked away from the keyboard to make sure what I was reading was fact not fiction. Again and again and again I went to visit as member of this forum, he was in deep need of help. He did not get it.

He has over 100 03 and 03A3 bolts, at the time I had 35 new old stock bolts. All he wanted to do was shorten the length of the chamber .0025". Before we started I assured him we did not have one bolt between us that would shorten his chamber.

When it comes to checking chamber length from the shoulder of the chamber to the bolt face I have some most unusual bolts. When it comes to using a pull through reamer the same bolts are considered usual. I have taken them to gun shows, placed them on the table and no one noticed they were different. I did get one compliment; the smith wanted to know why I screwed that HO bolt up.

F. Guffey

gjungle56
04-09-2020, 04:47
After a check of my bolts in a stripped receiver, I stand by the B&S bolts being longer. I put the bolts in the stripped receiver and depth miked down from receiver face to bolt face. The B&S bolts (3) were longer, though I found one SHT bolt even longer. I would not feel cheated, as all your bolts are apparently longer. Still puzzled though, how do you check chamber, clearance,and headspace without gages. Do you have some verified dimension cases used for this purpose? If so, how were they verified? Perhaps by defining the terms you use, it would clear up what you are trying to communicate. What is "chamber", "clearance", "usual and unusual bolts" ?

Sgt USMC
04-09-2020, 03:41
I'm the OP on this thread. I'm not sure how this got off topic, but I do not believe that I ask about the chamber on this weapon. With most weapons systems, motorcycles, cars, engines etc etc there are tricks of the trade for that particular model. Since I am not well versed on those of the Springfield I came here in the hopes that someone may have faced this situation, before, and if so what solution had they used. I was not trying to start a pissing contest between the esteemed members of this board. That being said. Maybe I should have ask it this way;

How do you make sure that the front sight post, on an 03A3 barrel, is vertical when mounting it on an 03 receiver, that has had the witness mark removed by the previous owner.

Question 2; Does anyone have dimensional drawing of the location of the '"Hatcher Hole" on the same weapon. Thank you everyone who has contributed to this discussion!

fguffey
04-09-2020, 05:09
How do you make sure that the front sight post, on an 03A3 barrel, is vertical when mounting it on an 03 receiver, that has had the witness mark removed by the previous owner.

Nothing has changed, you must screw the barrel into the receiver to determine how the shoulder at the end of the threads seat against the front of the receiver. If the sight post aligns check the extractor groove alignment. If the extractor cut aligns and the sight post aligns check the length of the chamber from the shoulder to the bolt face.

If the chamber is long, move the barrel back, if the chamber is short ream the chamber. If there is a problem with alignment find help.

F. Guffey

Hatcher hole; I never try to fool anyone, I want the hot high pressure metal cutting gas to have an exit. I try to do all of the hot high metal cutting escape gas system done before I worry about the Hatcher hole. I am a fan of checking case head protrusion/case head support. I have always been able to have the case head .090" above the bottom of the extractor cut.

Before someone starts pissing the 03 has less case head protrusion than the Mauser. The Mauser has .110" case head protrusion with an additional .005" clearance.

F, Guffey

lyman
04-09-2020, 07:29
I'm the OP on this thread. I'm not sure how this got off topic, but I do not believe that I ask about the chamber on this weapon. With most weapons systems, motorcycles, cars, engines etc etc there are tricks of the trade for that particular model. Since I am not well versed on those of the Springfield I came here in the hopes that someone may have faced this situation, before, and if so what solution had they used. I was not trying to start a pissing contest between the esteemed members of this board. That being said. Maybe I should have ask it this way;

How do you make sure that the front sight post, on an 03A3 barrel, is vertical when mounting it on an 03 receiver, that has had the witness mark removed by the previous owner.

Question 2; Does anyone have dimensional drawing of the location of the '"Hatcher Hole" on the same weapon. Thank you everyone who has contributed to this discussion!

somewhere, and I am not sure where, I have a book that was put out a good while ago that has the drawings for the 1903 , as in machinist drawings,

I would need to look in several places, ,,,,,



meanwhile as Guffey mentioned, things should line up,

one way to do it is put the receiver in a vice and level it, then Starrett and others make small angled (90 degrees) levels, with a bubble on each 'leg',
touch that securely to the front sight post and see if it is upright,,,

gjungle56
04-10-2020, 06:05
Ok, getting front sight vertical. I have to assume you have limited measuring tools but the minimum needed would be a flat surface, a scale with a square head, another scale, and some parallels(tool bits, key stock or whatever). The front sight base of an o3a3 is about .720 in dia., the sight blade is .050. After screwing in barrel to a proper tightness, place assembly on parallel under receiver to clear recoil lug and under barrel somewhere to get assembly somewhat level. With scale and square head, place it against front sight base, with other scale, measure from upright scale square to front sight blade. The measured dimension should be .335 which on a scale is between 21/64 and 11/32. Put square head scale to other side of front sight base and measured dimension needs be equal to first side. If more or less rotation needed, adjust as necessary. As for Hatcher hole, I posted dimensions in my first post. It was arrived at by measuring existing Hatcher holes in receivers with this mod already done.