The typical lug lapping jigs utilizes a threaded plug with a spring loaded plunger to provide the thrust while lapping.

While this is nice it doesn't provide the truest lapping from a rifle system stand point. I therefore, want to lap my lugs while the barrel is installed. To do this I will essentially use a head spacing gage (go) with a spring loaded plunger (working just like a standard lapping jig) and then lap the lugs with the barrel installed. This will true up my lug surfaces to the chamber of the rifle. I therefore eliminate any error do to the squareness of the action threads/face and barrel.

I am curious if anyone has tried this before.

Todd E

I was only curious to see if any of the resident gunsmiths had done it this way.

Centerpunch,
To keep all your negative responses the same the german response should be nein not verboten. Verboten means forbidden, while nein means no.
Todd E

[This message has been edited by Todd E (edited 05-05-2002).]

quote:

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Originally posted by Todd E:
Has anyone tried this?

The typical lug lapping jigs utilizes a threaded plug with a spring loaded plunger to provide the thrust while lapping.

While this is nice it doesn't provide the truest lapping from a rifle system stand point. I therefore, want to lap my lugs while the barrel is installed. To do this I will essentially use a head spacing gage (go) with a spring loaded plunger (working just like a standard lapping jig) and then lap the lugs with the barrel installed. This will true up my lug surfaces to the chamber of the rifle. I therefore eliminate any error do to the squareness of the action threads/face and barrel.

I am curious if anyone has tried this before.

Todd E

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Good idea Todd for occasions when removing the barrel is not desired. Same cautions as just using bolt less extractor/ejector. Keep compund out of area it doesnt belong.

I don't see any accuracy benefit, however. Whatever method used, the spring tension is just to keep bolt lugs against receiver lugs until 100 % contact is made. Whether there is a slight misalignment in thrust of spring tension is not going to effect results IMHO.

Wally

Tom

quote:

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Originally posted by centerpunch:
RE: your criticism of the writing style and intent of my comment---Oofdah!, yah sure, you betcha, Ole

Todd E wrote�

A rhetorical question, wasting bandwidth.

(n.b. I added a comma, can you find it ?)

[This message has been edited by centerpunch (edited 05-05-2002).]

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I just can't see Todd's post as rhetorical. Looked to me like he was offering another way to lap lugs.

I sometimes ask for an opinion re something I'm already doing hoping to elicit alternate methods or improvements on my own. Hardly rhetorical.

Wally

quote:

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Originally posted by centerpunch:
wallyw:

This reply is off topic, but you raised the question of what I meant.

Sooooo, I do hope you would agree that there are rules valuable to, and for, effective discourse.

One that is universally accepted is:

It becomes problematic to all effective communication when a the listener's internal viewpoint i.e., personal interpretation is allowed to distort the meaning of what was, in this case, written.

If I may refer you to < http://www.m-w.com/dictionary.htm >

:Main Entry: rhe�tor�i�cal
Function: adjective
1 a : of, relating to, or concerned with rhetoric

b : employed for rhetorical effect; especially : asked merely for effect with no answer expected <a rhetorical question>

Given that Todd E stated in a subsequent post, that he had lapped lugs in this manner, his asking

quote:

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Has anyone tried this

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re: suggestions to lap lugs, makes the question rhetorical in nature, since it was obviously "asked merely for effect with no answer expected." because

1) "merely asked for effect"� that of getting responses from forum members

2) "with no answer expected"� since he ALREADY had the answer

That he may have been eliciting "suggestions" from others was NOT what he asked, stated or indicated in his original post.

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You are very sure of what the rest of us have on our minds?

Wally

centerpunch, wallyw,
What's with the dictionary definition? Please stop this kind of arguement. I know it's tempting to fight back, it just isn't worth your time, and wastes some of ours too.

Peace

I apologize for my previous response back to you. I assure you it was meant in JEST! I apologize further for my poor wording in my original post, which started this thread.

To clear up all misunderstandings. I have concocted this approach to lapping and used it only once before. I was interested in knowing if any of the gunsmith's here at tried this or something very similar. Furthermore, I figured I would provide an alternative form of lapping for anyone elses consideration. A more practical form has been put forward by the gentlemen using a spent case, a wooden dowel, and a bicycle inner tube. Very ingenius, I might add.

Centerpunch you seen to be rather ingnorant of the entire lapping procedure. You tell me I should not do it this way, but you offer no reasons why. I welcome enlightenment and constructive critism. I did neglect to mention the checking of head spacing, which I did amend in a proceding post.

I might add in the traditional form of lapping the gunsmith must check the headspace after lapping as well. He may have to adjust the head space after lapping, he may not. The advantage with my proposal would seem to be that the tolerance stack-up between the receiver, barrel, bore, and bolt face is minimized.

In the past (one and only time) I machined a plug out of bearing bronze which was essentially a reproduction of a "GO" head space gage. I installed a spring loaded plunger into this plug so as to create the thrust force upon the bolt face during lapping. It would very nicely, but requires to use of a lathe (which fortunately I have). I make a great deal of my own tooling for my hobbies. You can save a great deal of money this way, and sometimes even improve upon the status quo. Again I like the case, dowel, inner tube idea that is trick.

Todd E

Where are you going to put the spring and plunger if you have a GO gauge in the chamber?

How are you going to adjust the headspace you create?

What you propose in no way increases the accuracy of the job. The squareness of the receiver depends on the bolt raceway and lug recess being straight and square with the receiver threads and the face of the action. These dimensions must be made right BEFORE the barrel is installed.

Lug lapping is a small part of a larger operation. Without the other processes lapping the lugs does little good.....like balancing a tire before it's mounted on the rim. Why bother if you have to do it all over again?