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Posted: 2/22/2011 12:12:38 PM EDT
[#1]
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I was always told if you ask 10 machinist how to do something that you will get 15 different answers. How true!!!! 
+2 
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Posted: 2/22/2011 5:39:24 PM EDT
[#2]
do these dudes not realize you can indicate the ID of the bore in while holding the OD in a 4 jaw chuck??
nice job |
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Posted: 2/22/2011 6:07:06 PM EDT
[#3]
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do these dudes not realize you can indicate the ID of the bore in while holding the OD in a 4 jaw chuck?? nice job Pin gages own them |
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Posted: 2/22/2011 6:24:34 PM EDT
[#4]
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do these dudes not realize you can indicate the ID of the bore in while holding the OD in a 4 jaw chuck?? VrodRay, why not re-chuck the thing and do that,.. just to shut everybody up? 
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Posted: 2/22/2011 6:38:46 PM EDT
[#5]
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do these dudes not realize you can indicate the ID of the bore in while holding the OD in a 4 jaw chuck?? VrodRay, why not re-chuck the thing and do that,.. just to shut everybody up?
I'll get right on that! Screw the rest of the stuff we machine that require a 4 jaw chuck.
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Posted: 2/22/2011 6:42:11 PM EDT
[#6]
I am a CNC machinist with around 15 yrs of experience, with that said there is nothing wrong with what the OP did. Is it the best way, that is debatable. As long as he checked the runout of the inside diameter with an indicator then the machine work will be fine.
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Posted: 2/22/2011 6:43:46 PM EDT
[#7]
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Did you cut the threads centered off the OD? I was wondering about that myself. The dial indicator lead me in that direction. |
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Posted: 2/22/2011 6:48:04 PM EDT
[#8]
"By the way, 2 hour turn around time"
Ha!! I love it................
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Posted: 2/22/2011 7:11:53 PM EDT
[#9]
this thread was fun
 . Now i need some DPMS hate and i think i got enough tec discussion for the day |
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Posted: 2/22/2011 7:18:57 PM EDT
[#10]
Ill tell you what im sick of..members who display behavior jumping to conclusions and attacking and acusing someone that they did something wrong is generally unacceptable but its OK for a dealer to do it.I respect ADCO and have had work from them but you know what this shit has to stop with EVERYONE just not a select few
 Then he gets accused of unpaid advertising when hes not hes showing off what he did and proud of it he didnt list prices for work or try to solicite buisness....ill tell you what I think it is..... fear of competition from someone whos not trying to compete or maybe the same dealer will go back to bashing other companies who make claims about their double chromelined barrels and that will turn into a shit fest..enough already ...fucking enough.
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Posted: 2/22/2011 7:34:25 PM EDT
[#11]
 To above. Op thanks for the pics. Thanks to all who shared the technical info (I learned something).
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Posted: 2/22/2011 9:08:56 PM EDT
[#12]
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Well, the problem with doing the threads of the OD is that if the bore isnt concentric, you will now get baffle strikes. you never, ever, setup barrel threads based on the OD of the barrel, you set up the threads concentric to the bore. I had an amateur smith ruin a barrel of mine this way.... thankfully it was only a 10/22 barrel.... Hope that works out for your customer.... What he said ^ Most all bores aren't concentric to the OD. You should have this thread trashed quick. Pun intended Thread trashed? How so? I just stated above that before anyting was cut the ID was checked. while the job looks great, the OD is pretty much meaningless and i personally wouldn't trust the bore chamfer at all....stick a range rod in there and dial it in at least two places on the range rod to .0001 and you won't have to worry about baffle strikes. front and back spiders help a lot with this. not trying to be an ass or anything, it's just the most accurate/best way a lot of us have found to make threads you never have to worry about. |
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Posted: 2/22/2011 9:18:50 PM EDT
[#13]
Quoted: Ill tell you what im sick of..members who display behavior jumping to conclusions and attacking and acusing someone that they did something wrong is generally unacceptable but its OK for a dealer to do it.I respect ADCO and have had work from them but you know what this shit has to stop with EVERYONE just not a select few Then he gets accused of unpaid advertising when hes not hes showing off what he did and proud of it he didnt list prices for work or try to solicite buisness....ill tell you what I think it is..... fear of competition from someone whos not trying to compete or maybe the same dealer will go back to bashing other companies who make claims about their double chromelined barrels and that will turn into a shit fest..enough already ...fucking enough.i thought that it was unprofessional for ADCO to comment like that. i am little  . They are a business not some 300 lb virgin in his underwear posting from his moms basement.
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Posted: 2/22/2011 9:29:31 PM EDT
[#14]
Quoted:
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Ill tell you what im sick of..members who display behavior jumping to conclusions and attacking and acusing someone that they did something wrong is generally unacceptable but its OK for a dealer to do it.I respect ADCO and have had work from them but you know what this shit has to stop with EVERYONE just not a select few Then he gets accused of unpaid advertising when hes not hes showing off what he did and proud of it he didnt list prices for work or try to solicite buisness....ill tell you what I think it is..... fear of competition from someone whos not trying to compete or maybe the same dealer will go back to bashing other companies who make claims about their double chromelined barrels and that will turn into a shit fest..enough already ...fucking enough.i thought that it was unprofessional for ADCO to comment like that. i am little . They are a business not some 300 lb virgin in his underwear posting from his moms basement. +1 to both big turn off. Personally if I had to pick I would rather give my business to the OP than to the one mentioned above business. I am sure I will be put in my place for this but this is just my opinion nothing more. |
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Posted: 2/22/2011 10:12:04 PM EDT
[#15]
Call me crazy, but I thought ADCO was trying to help the guy out.
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Posted: 2/22/2011 10:15:38 PM EDT
[#16]
Quoted: Quoted: Quoted: Quoted: Well, the problem with doing the threads of the OD is that if the bore isnt concentric, you will now get baffle strikes. you never, ever, setup barrel threads based on the OD of the barrel, you set up the threads concentric to the bore. I had an amateur smith ruin a barrel of mine this way.... thankfully it was only a 10/22 barrel.... Hope that works out for your customer.... What he said ^ Most all bores aren't concentric to the OD. You should have this thread trashed quick. Pun intended Thread trashed? How so? I just stated above that before anyting was cut the ID was checked. If you customer has the one in a million barrel with 0 runout, good for him. If its off just a few thousandths he'll have a very noticeable POI shift, if its off 7 or more thousandths hes asking for a baffle strike. I mean this in the nicest way, I'm suggesting you have this thread deleted because you are admitting you dont know how to thread a rifle barrel properly. this doesn't sound like help to me |
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Posted: 2/22/2011 11:02:52 PM EDT
[#17]
ADCO reminded me of the line from Shakespeare: Me thinks he doth protest too much:
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Posted: 2/22/2011 11:12:47 PM EDT
[#18]
Think it turned out decent for their first one. Would like a range report also. Neat that it was done while assembled. Don't think I'm quite ready to tackle that job.
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Posted: 2/23/2011 3:22:30 AM EDT
[#19]
I think that ADCO's comments here are well intentioned. I don't think they will care if anyone starts another shop... they have more than enough work than they can handle. I am sure they have fixed many barrels that someone else has done and they are just trying to give some advice based on their experience. I also think they wanted to make sure that the correct information was given on a thread so most folks don't turn a barrel themselves based on the OD (Think this is outside diameter). If the I am understanding this... If ID (Inside diameter) is the same as BORE and it was checked based on this then it is for this barrel it is ok. But from what I also am getting from this is the OP got lucky. If the barrel was not concentric ( think I am using the right term) to the OD and they turned it based on this....... and it was off then the job would have to be done over again anyway.
Its time to put the ego's away. Basically the op got his hackles up because he thought ADCO was saying "Hey you guys suck" and that wasn't the case in the initial reply by them at all. When the OP dug in ADCO dug in and the Apples and oranges or the Apples to Apples debate began. I want to say I am no way affiliated with ADCO. I haven't even had work done by them... but would based on reputation here in general from what I have seen. Can Bigbore get opinionated if he gets annoyed .... yes. Is the ADCO shop all warm and fuzzy..... from what I have read on the boards... no but they do darn good work. Good Luck Striker |
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Posted: 2/23/2011 4:23:58 AM EDT
[#20]
Public forums like this are a great source for information, and an even greater source for misinformation. As a site sponsor, I'd be doing a great disservice to the members if I saw misinformation being posted and did not say anything. The technique presented here is the wrong way to thread a barrel - even more so for a suppressor mount. I've always been more concerned with getting my point across than with being polite.
This is how you properly indicate off the bore. 
For more info on barrel threads, here is a post from a while back. |
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Posted: 2/23/2011 4:24:28 AM EDT
[#21]
First, nice looking job. It blends in very well with the rifle.
I think the thing that hasn't been explicitly stated yet is that even if the OD and ID are perfectly concentric at the muzzle, they may diverge along the length of the bore (due to tolerances in the boring process). The only way to really be sure of the direction of the bore is to insert a snugly fitting rod and indicate off that. |
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Posted: 2/23/2011 4:35:23 AM EDT
[#22]
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Did you cut the threads centered off the OD? I saw that to. You should cut the threads after centering the bore. |
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Posted: 2/23/2011 4:37:01 AM EDT
[#23]
I think that looks great.
I have a technical question as a guy not really familiar with machining. Obviously, for a flashhider concentricity is not that big a deal, but for a silencer it is. If you were doing this work for a silencer, how would you ensure that the threads are concentric to the bore, not just the outside of the barrel? Thanks. |
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Posted: 2/23/2011 4:44:12 AM EDT
[#24]
Quoted:
Public forums like this are a great source for information, and an even greater source for misinformation. As a site sponsor, I'd be doing a great disservice to the members if I saw misinformation being posted and did not say anything. The technique presented here is the wrong way to thread a barrel - even more so for a suppressor mount. I've always been more concerned with getting my point across than with being polite. This is how you properly indicate off the bore. http://www.adcofirearms.com/detailpics/roundcheck.jpg For more info on barrel threads, here is a post from a while back. Bigbore, thanks for the picture. So you insert a rod in the bore, measure the runout, then adjust the chuck on the lathe so that runout = zero? I'm just curious, fascinating stuff. |
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Posted: 2/23/2011 4:45:54 AM EDT
[#25]
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No one is arguing process here, we are both in absolute agreement that the ID is what should be used as reference for cutting the thread. It's just that bigbore had jumped to conclusions as if I had said both the OD and the ID were completely concentric. All I had said was that I began on the OD and got close and then checked the ID and happened to be right on the money. Some of you guys are like a sewing circle having read two posts and you've got the whole story down. I'm of the school of thought where if I saw work of this caliber, I might start the sentence off with, nice work, or clean job etc, and not ask "how'd you do it" right off the bat and then proceed to tell you you don't know what you are doing......but that's just me, I must be crazy. By the way, 2 hour turn around time. He didn't jump to conclusions. He based his statement off of what you pictured. From a process perspective, it makes no sense indicate the OD then go back and reset on the bore. |
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Posted: 2/23/2011 5:01:27 AM EDT
[#26]
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while the job looks great, the OD is pretty much meaningless and i personally wouldn't trust the bore chamfer at all..... Good point, indicating off the OD, then checking that against the chamfer isn't going to help anything; and let me explain why. - crowns / chamfers / muzzles are probably very close to concentric to the OD - NOT the bore. Where the bore is in the barrel really isnt important. This usually never comes up, because if you don't have a suppressor, none of this matters. If you are putting a suppressor on the barrel, it must be done right - concentric to the bore. |
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Posted: 2/23/2011 5:10:18 AM EDT
[#27]
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No one is arguing process here, we are both in absolute agreement that the ID is what should be used as reference for cutting the thread. It's just that bigbore had jumped to conclusions as if I had said both the OD and the ID were completely concentric. All I had said was that I began on the OD and got close and then checked the ID and happened to be right on the money. Some of you guys are like a sewing circle having read two posts and you've got the whole story down. I'm of the school of thought where if I saw work of this caliber, I might start the sentence off with, nice work, or clean job etc, and not ask "how'd you do it" right off the bat and then proceed to tell you you don't know what you are doing......but that's just me, I must be crazy. By the way, 2 hour turn around time. He didn't jump to conclusions. He based his statement off of what you pictured. From a process perspective, it makes no sense indicate the OD then go back and reset on the bore. He absolutely did. I never posted this thread as a write up on my step by step process, merely adding a picture or two of the process for the hell of it. I don't see a picture of a car half preped for paint with body filler on it, and then see a picture of the finished product and say "you should have primed it it makes no sense". As I've mentioned multiple times above I did dial in on the ID chamfer before cutting. _________________ I do have a set of pin gages however as stated in the title, this being my first barrel, as well as being new to AR's, there will be a slight learning curve. I was under the impression that the ID chamfer would be concentric with the bore. If it's not wouldn't that by itself effect the accuracy somewhat? I appreciate the info on that and will dial it in properly next time. I'll be sure to put detailed pictures of my runout if I ever intend on posting them. |
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Posted: 2/23/2011 5:21:52 AM EDT
[#28]
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I was under the impression that the ID chamfer would be concentric with the bore. If it's not wouldn't that by itself effect the accuracy somewhat? Off center / oblong crowns / chamfers will have an effect on POI, not accuracy because they are a constant. Again, it doesn't matter to the barrel or flash hider. Search any number of threads of people who had barrels cut down/threaded and most will mention a POI shift, and possibly an accuracy increase. When the barrel is chucked up for threading, centered off the bore, its always a good extra step to recut the crown centric to the bore even if its not going to be used with a suppressor. |
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Posted: 2/23/2011 5:22:05 AM EDT
[#29]
Quoted:
Public forums like this are a great source for information, and an even greater source for misinformation. As a site sponsor, I'd be doing a great disservice to the members if I saw misinformation being posted and did not say anything. The technique presented here is the wrong way to thread a barrel - even more so for a suppressor mount. I've always been more concerned with getting my point across than with being polite. This is how you properly indicate off the bore. http://www.adcofirearms.com/detailpics/roundcheck.jpg For more info on barrel threads, here is a post from a while back. That's cool. How do you adjust for run-out on a six jaw chuck? ETA: Googled, it, just like a four jaw independent chuck. |
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Posted: 2/23/2011 5:49:34 AM EDT
[#30]
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Call me crazy, but I thought ADCO was trying to help the guy out. Just because you're crazy doesn't mean you're wrong 
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Posted: 2/23/2011 5:51:37 AM EDT
[#31]
Quoted: Quoted: Public forums like this are a great source for information, and an even greater source for misinformation. As a site sponsor, I'd be doing a great disservice to the members if I saw misinformation being posted and did not say anything. The technique presented here is the wrong way to thread a barrel - even more so for a suppressor mount. I've always been more concerned with getting my point across than with being polite. This is how you properly indicate off the bore. http://www.adcofirearms.com/detailpics/roundcheck.jpg For more info on barrel threads, here is a post from a while back. That's cool. How do you adjust for run-out on a six jaw chuck? ETA: Googled, it, just like a four jaw independent chuck. I was just about to ask the same thing. |
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Posted: 2/23/2011 6:23:53 AM EDT
[#32]
Seemed like Adco was looking out for the guy. It was his first barrel. If I was doing something for the first time I'd like some input from an expert prior to delivering my product to a customer that way I could fix anything if necessary. It would be worse if the customer received my product and then had some problems. Just my 2 cents.
OP, your work seems to be very good and I'm sure you will quickly master the process through repetition. Good luck. |
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Posted: 2/23/2011 6:26:41 AM EDT
[#33]
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Nice job. The main thing I like about the thread is the disclosure that apparently most regular production barrels have a bore that is a little 'off' from being perfectly concentric. This is interesting because when it was discovered that some CMMG barrels were like that a few years ago, you would have thought that they were the only company selling such barrels judging by the indignant comments posted here. As I recall, "a little 'off'" was not the description used. |
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Posted: 2/23/2011 7:35:04 AM EDT
[#34]
Pics show indicating off the OD. Bigbore did the proper thing to advise against the wrong method that was shown in the pics by the OP. I used to machine flight safety and flight critical parts for the aerospace industry, so I have a basic knowledge about machining.
I guess some people like learning the hard way.
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Posted: 2/23/2011 8:04:13 AM EDT
[#35]
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Pics show indicating off the OD. Bigbore did the proper thing to advise against the wrong method that was shown in the pics by the OP. I used to machine flight safety and flight critical parts for the aerospace industry, so I have a basic knowledge about machining. I guess some people like learning the hard way.
I give up, it's like talking to 5 yr olds.......for the 4 or 5th time now.....I went off of the ID chamfer. Now, learning that the ID chamfer is not necessarily concentric with the bore is a different story. I was under the impression that if a barrel maker wanted their barrel to have the correct POI they would make their chamfer using the bore as reference and not the OD. |
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Posted: 2/23/2011 8:04:49 AM EDT
[#36]
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Looking at the pictures, I don't see any baffles in that flash suppressor, Oh, wait, wut, OK now I remember, Flash hiders aren't supposed to have baffles....................... Looks like a pretty good job, better than I could do. And welcome to arfcom, the source of more info than wikipedia. It is a suppressor mount. YOu win the FAIL of the day for this post. |
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Posted: 2/23/2011 8:16:56 AM EDT
[#37]
Thank God nobody has mentioned spiders yet.
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Posted: 2/23/2011 9:03:05 AM EDT
[#38]
Quoted:
Quoted:
Pics show indicating off the OD. Bigbore did the proper thing to advise against the wrong method that was shown in the pics by the OP. I used to machine flight safety and flight critical parts for the aerospace industry, so I have a basic knowledge about machining. I guess some people like learning the hard way.
I give up, it's like talking to 5 yr olds.......for the 4 or 5th time now.....I went off of the ID chamfer. Now, learning that the ID chamfer is not necessarily concentric with the bore is a different story. I was under the impression that if a barrel maker wanted their barrel to have the correct POI they would make their chamfer using the bore as reference and not the OD. I'm glad to see we all now know that centering off ANYTHING other than the bore is wrong. I thought even a 5 yr old would have known that.
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Posted: 2/23/2011 9:20:27 AM EDT
[#39]
Quoted:
Quoted:
Quoted:
Pics show indicating off the OD. Bigbore did the proper thing to advise against the wrong method that was shown in the pics by the OP. I used to machine flight safety and flight critical parts for the aerospace industry, so I have a basic knowledge about machining. I guess some people like learning the hard way.
I give up, it's like talking to 5 yr olds.......for the 4 or 5th time now.....I went off of the ID chamfer. Now, learning that the ID chamfer is not necessarily concentric with the bore is a different story. I was under the impression that if a barrel maker wanted their barrel to have the correct POI they would make their chamfer using the bore as reference and not the OD. I'm glad to see we all now know that centering off ANYTHING other than the bore is wrong. I thought even a 5 yr old would have known that.
I wasn't referring to you directly, but watch, there will be a few more to follow you. "Dialing in on the OD is wrong" Sometime it helps to read what was already discussed. and you're right, a 5 yr old would have the knowledge of machining and concentricity. |
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Posted: 2/23/2011 9:23:21 AM EDT
[#40]
you guys are making a big deal about indicating off ONE SPOT on the ID of the muzzle end. if you are doing a non precision AR build then I agree, thats the right way to do it. now go talk to the top smiths that build benchrest and precision rifles. they'll
you.
put a tenths indicater on the muzzle end, mount the chamber end on the back side of the headstock in a catshead. indicate BOTH ends for concentricity to make sure your threads and crown are perfectly on centerline of the lathe. same locating method is used for chambering. (bad pic. I know, but its the only decent pic of a cat head chuck I could find) 
the OP did it his way. and from the looks of it did it right. he checked the ID |
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Posted: 2/23/2011 9:41:01 AM EDT
[#41]
I want to thank the OP and BigBore for the knowledge that's been put forth in this thread. I'm not a machinist and all of this has been extremely fascinating to me.
Op, after this thread, will you do the next one the same way, or will you make changes? I am not flaming in any way, but I am curious. As a non-machinist, I'm not even 100% sure that I understood everyting that I read. I am also curious as to how you put a rod into a barrell tight enough to center the bore, without risk of damaging the barrel. I would think the rod would have to go pretty far into the barrell. Maybe I'm not understanding that part? |
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Posted: 2/23/2011 9:59:15 AM EDT
[#42]
Quoted: I want to thank the OP and BigBore for the knowledge that's been put forth in this thread. I'm not a machinist and all of this has been extremely fascinating to me. Op, after this thread, will you do the next one the same way, or will you make changes? I am not flaming in any way, but I am curious. As a non-machinist, I'm not even 100% sure that I understood everyting that I read. I am also curious as to how you put a rod into a barrell tight enough to center the bore, without risk of damaging the barrel. I would think the rod would have to go pretty far into the barrell. Maybe I'm not understanding that part? Same here. I was thinking it might be like the rods used on bore sights, but that something like that may not be precise enough. Too complicated for me. |
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Posted: 2/23/2011 10:10:07 AM EDT
[#43]
This is how, pin gages, find the one that fits perfectly and dial in from that. Would I do it differently? Yes, I would use the pin gage technique since I didn't think of it at the time. Having thought the ID chamfer was completely concentric with the bore, I essentially thought I was doing the same thing when using the ID chamfer as reference before cutting. So I thank Bigbore and the others for showing me that. But other then that I feel I planed this threading out pretty well. |
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Posted: 2/23/2011 10:37:01 AM EDT
[#44]
Quoted:
http://i373.photobucket.com/albums/oo180/CopperAndBlack/444f91c9.jpg This is how, pin gages, find the one that fits perfectly and dial in from that. Would I do it differently? Yes, I would use the pin gage technique since I didn't think of it at the time. Having thought the ID chamfer was completely concentric with the bore, I essentially thought I was doing the same thing when using the ID chamfer as reference before cutting. So I thank Bigbore and the others for showing me that. But other then that I feel I planed this threading out pretty well. Can you expain what the ID chamfer is and how it's different that the pin gage method? Your work looks very good to me. I always thought that being a machinist would be a good trade to know.
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Posted: 2/23/2011 10:59:54 AM EDT
[#45]
Quoted:
Quoted:
http://i373.photobucket.com/albums/oo180/CopperAndBlack/444f91c9.jpg This is how, pin gages, find the one that fits perfectly and dial in from that. Would I do it differently? Yes, I would use the pin gage technique since I didn't think of it at the time. Having thought the ID chamfer was completely concentric with the bore, I essentially thought I was doing the same thing when using the ID chamfer as reference before cutting. So I thank Bigbore and the others for showing me that. But other then that I feel I planed this threading out pretty well. Can you expain what the ID chamfer is and how it's different that the pin gage method? Your work looks very good to me. I always thought that being a machinist would be a good trade to know.
Think of the chamfer as the crown, or the angled cut where the bore ends. That cut may have been made while being centered off the outside diameter (outside of barrel, which likely the bore is not perfectly centered in). So, by indicating off a pin in the bore, you can find the true center of the bore. Then you set up the machine to cut with it's zero set to the middle of the bore. |
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Posted: 2/23/2011 11:00:41 AM EDT
[#46]
Quoted:
Quoted:
http://i373.photobucket.com/albums/oo180/CopperAndBlack/444f91c9.jpg This is how, pin gages, find the one that fits perfectly and dial in from that. Would I do it differently? Yes, I would use the pin gage technique since I didn't think of it at the time. Having thought the ID chamfer was completely concentric with the bore, I essentially thought I was doing the same thing when using the ID chamfer as reference before cutting. So I thank Bigbore and the others for showing me that. But other then that I feel I planed this threading out pretty well. Can you expain what the ID chamfer is and how it's different that the pin gage method? Your work looks very good to me. I always thought that being a machinist would be a good trade to know.
Well the ID chamfer (crown in gunsmith terms I believe) is the angled cut right there at the end of the bore of the barrel. It is there so it allows uniform release of the gasses. So if it’s off then theoretically the shot will be pushed to the side with the least resistance on the way out, obviously changing your POI. Now if I was making barrels and knew this, I would make for damn sure that that chamfer is concentric with the bore. Now I find out that barrel makers apparently don’t care as much and there is a possibility that it might not be completely concentric with the bore so then its the barrel itself is not done correctly. What I did was rely on what I thought was common barrel manufacturing procedure for a correct POI, and not actually dial in the bore itself. So in the off chance the crown is off then the thread would then be off by the same amount. With the Pin gage you would be taking reading of the actual bore, thus eliminating any chance of error |
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Posted: 2/23/2011 11:02:42 AM EDT
[#47]
Quoted:
Quoted:
Quoted:
http://i373.photobucket.com/albums/oo180/CopperAndBlack/444f91c9.jpg This is how, pin gages, find the one that fits perfectly and dial in from that. Would I do it differently? Yes, I would use the pin gage technique since I didn't think of it at the time. Having thought the ID chamfer was completely concentric with the bore, I essentially thought I was doing the same thing when using the ID chamfer as reference before cutting. So I thank Bigbore and the others for showing me that. But other then that I feel I planed this threading out pretty well. Can you expain what the ID chamfer is and how it's different that the pin gage method? Your work looks very good to me. I always thought that being a machinist would be a good trade to know.
Think of the chamfer as the crown, or the angled cut where the bore ends. That cut may have been made while being centered off the outside diameter (outside of barrel, which likely the bore is not perfectly centered in). So, by indicating off a pin in the bore, you can find the true center of the bore. Then you set up the machine to cut with it's zero set to the middle of the bore. "May had" nothing, I know what I did. So now I'm a liar as well? |
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Posted: 2/23/2011 11:06:59 AM EDT
[#48]
Quoted: Can you expain what the ID chamfer is and how it's different that the pin gage method? Think about it. Is the crown chamfer (ID chamfer) cut on the rifling machine or on the lathe? The chamfer is just there to break the sharp edge on the crown. |
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Posted: 2/23/2011 11:10:38 AM EDT
[#49]
Quoted: "May had" nothing, I know what I did. So now I'm a liar as well? No, you just suck horribly at reading comprehension, and you have a hard time taking criticism, constructive or otherwise... He wasn't saying YOU may have, he was talking about the barrel manufacturer... |
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Posted: 2/23/2011 11:15:10 AM EDT
[#50]
Quoted:
Quoted:
"May had" nothing, I know what I did. So now I'm a liar as well? No, you just suck horribly at reading comprehension, and you have a hard time taking criticism, constructive or otherwise... He wasn't saying YOU may have, he was talking about the barrel manufacturer... "Think of the chamfer as the crown, or the angled cut where the bore ends. (End of sentence) That cut (Sounds like he is referring to the cut I made and not any chamfer) may have been made while being centered off the outside diameter." My reading comprehension is just fine, thank you. And I absolutely don't have a problem taking constructive criticism, I welcome it, in fact I'm of the school of thought of you can never know everything. That being said when I have to constantly reiterate the fact that I dialed in the ID chamfer and not the OD, all because I forgot to include a fucking picture of the dial sitting on that face. Then yeah I might get a little testy. and then when I am not believed and am basically being called a liar then yes I might even get a little more testy. |
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