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- May 14, 2013
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Does anyone have a PTG(TM) micrometer reamer stop they would be willing to share some dimensions with me? I am undertaking my first re barrel / chamber job and can use all the help I can get. Thanks in advance.
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Micrometer reamer stop ?
- Thread starter blaser.306
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- Oct 31, 2016
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Chambering some barrels is also on my to do list. I would like this info too. Did a quick search looking for plans for a reamer stop and didn't find any. They seem to be pretty simple and I would think fairly easy to make. After reading PTG's description the most critical dimension is the fit of the stop to the body of the reamer. There seems to be two styles. One slips over the reamer body with the reamer held in a chuck in the tailstock. The other style the reamer fits inside the stop and the stop is held in a chuck in the tailstock. This style would be harder to make.
There are only two pieces. Both tubes. The inner tube is bored to the OD of the reamer body and has a couple of set screws to hold it to the reamer. I picked 1" for the OD and an ID of .473. The outer tube would have a portion where the ID was 1" and and the remainder with an ID of the minor diameter of the chosen thread. I picked 1.25" for the OD of this tube. The length of both tubes would depend on the length of the reamer body. Seems pretty simple to me. I must be missing something.
There are only two pieces. Both tubes. The inner tube is bored to the OD of the reamer body and has a couple of set screws to hold it to the reamer. I picked 1" for the OD and an ID of .473. The outer tube would have a portion where the ID was 1" and and the remainder with an ID of the minor diameter of the chosen thread. I picked 1.25" for the OD of this tube. The length of both tubes would depend on the length of the reamer body. Seems pretty simple to me. I must be missing something.
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Thanks for the reply , I had come up with a similar plan also with tubes , but mine will be using three. The inner that is fastened to the reamer body, and the outer that will be used for the "stop" and then a lock collar. All of the above pieces will be single point threaded to 7/8"-40 TPI so as to give 25 divisions on a full rotation of the collar each being 1 thou of advancement. Hopefully I will get this done on holidays and post some pictures of success ( and failures ) .
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I have this tool and never used it. When I get ready to chamber I just have at it with a floating reamer holder in the tailstock and use the DRO to set headspace. As quick and as accurate as needed. I build benchrest rifles that are very competitive. I bought this device because I was intrigued as to how accurate you can set headspace. I might play with it some day.
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It would be nice to have DRO's for the lathe and the mill. Not going to happen anytime soon.
I forgot to show the collar in my drawing. Thinking more about it you could make it with a 1/4 20 cap screw or bolt. Something like this.
One problem I have is that I have no way to mark the stop accurately with lines to show each .001. One full revolution of a 1/4 20 bolt moves .050. Each point on the bolt head represents 1/6 of .050 for .00833 movement. My understanding of this is that you can pick any distance that you want to stop the reamer. Then move the stop to zero and finish reaming. The points on the bolt head should be close enough. Or you could use a caliper or depth micrometer to set the stop to wherever you want it to stop the reamer.
Another project added to the list.
I forgot to show the collar in my drawing. Thinking more about it you could make it with a 1/4 20 cap screw or bolt. Something like this.
One problem I have is that I have no way to mark the stop accurately with lines to show each .001. One full revolution of a 1/4 20 bolt moves .050. Each point on the bolt head represents 1/6 of .050 for .00833 movement. My understanding of this is that you can pick any distance that you want to stop the reamer. Then move the stop to zero and finish reaming. The points on the bolt head should be close enough. Or you could use a caliper or depth micrometer to set the stop to wherever you want it to stop the reamer.
Another project added to the list.
Last edited:
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How do you set headspace with the DRO?
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- Dec 22, 2014
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I have a DRO on the tailstock quill.
And an indicator on the lathe bed so the carriage always returns to the exact same position. All chambering is done through the headstock with a spider on outboard end
And an indicator on the lathe bed so the carriage always returns to the exact same position. All chambering is done through the headstock with a spider on outboard end
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- Oct 24, 2019
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I have a Lambeth/Kiff adjustable reamer stop. I attached the instructions. Mine is set up for the chamber of my personal competition rifles. I haven't adjusted it in years. I can use any brass that I have in any of my rifles. Sorry, I will not dissemble it it measure. I do have some additional pieces (different body lengths) that can be measured.
Hope this helps.
Hope this helps.
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- Oct 24, 2019
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I understand that this works for you. That is great. I am confused as to where you start your measurement from, i.e. when do you set your dro to zero?
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Thanks for the download of the reamer use sheets, That confirms all my suspicions were dead nuts on. I can start my next series of projects now. I will post as I go. Reamer and go gauge should only be a couple months away , barrel another 4-5 weeks ! With any luck I should have a complete XP-100 by spring!