Barrel Porting.. can it be done on the ktichen table?

Barrel Porting.. can it be done on the ktichen table?

Joined: March 1st, 2002, 12:22 am

May 7th, 2012, 5:37 pm #1


Rob mentioned below about  just buying an extra barrel,and porting it.

Great idea, and to be honest had thought of it, and quickly discarded the thought.

The reason for that is, its my recollection (and already suspect ) that you need EDM equipment, or very sharp tools and machining experience to get a clean hole in the barrel.

If you just drill a hole into a tube, when the bit breaks thru the interior wall (into the bore) it leaves little bits of metal that protrude into the bore.

So unless some one has a away to clean the "flash" from the bit out of the bore, I just dont see how a drill press jockey can get decently clean hole for porting......

If it'll help the SSR cause, I'm willing to be wrong......  


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the Lunatic Fringe of American Airgunning
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Joined: November 17th, 2006, 3:51 am

May 7th, 2012, 6:40 pm #2

..and work the burr down on the inside fo the barr

HAve done the job for times, twice when rebarreling QBs and twice rebarreling Crosmans. Of the two, Crosmans are easier (the port is closer to the rear of the barrel and easier to remove the burr).

If you have patience, can work the burr smooth with thin wooden dowel (wooden BBQ skewers will work)...glue...and small bits of abrasive paper. Glue a tiny pad to the short length of dowel and work on JUST the burr. Have to do refresh the paper pretty often.

Check would be to chamber a pellet and then push it back out from the muzzle with a rod. If there is a burr, the pellet will catch on it and have a bite mark on the skirt.
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Joined: April 28th, 2010, 12:23 am

May 7th, 2012, 6:44 pm #3

Rob mentioned below about  just buying an extra barrel,and porting it.

Great idea, and to be honest had thought of it, and quickly discarded the thought.

The reason for that is, its my recollection (and already suspect ) that you need EDM equipment, or very sharp tools and machining experience to get a clean hole in the barrel.

If you just drill a hole into a tube, when the bit breaks thru the interior wall (into the bore) it leaves little bits of metal that protrude into the bore.

So unless some one has a away to clean the "flash" from the bit out of the bore, I just dont see how a drill press jockey can get decently clean hole for porting......

If it'll help the SSR cause, I'm willing to be wrong......  


dr_subsonic's pneumatic research lab

the Lunatic Fringe of American Airgunning
Southwest Montana's headquarters for Airgunning Supremacy
Proud Sponsor of team_subsonic
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Joined: June 2nd, 2009, 12:39 pm

May 7th, 2012, 6:48 pm #4

Rob mentioned below about  just buying an extra barrel,and porting it.

Great idea, and to be honest had thought of it, and quickly discarded the thought.

The reason for that is, its my recollection (and already suspect ) that you need EDM equipment, or very sharp tools and machining experience to get a clean hole in the barrel.

If you just drill a hole into a tube, when the bit breaks thru the interior wall (into the bore) it leaves little bits of metal that protrude into the bore.

So unless some one has a away to clean the "flash" from the bit out of the bore, I just dont see how a drill press jockey can get decently clean hole for porting......

If it'll help the SSR cause, I'm willing to be wrong......  


dr_subsonic's pneumatic research lab

the Lunatic Fringe of American Airgunning
Southwest Montana's headquarters for Airgunning Supremacy
Proud Sponsor of team_subsonic
deburring tool.
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Joined: March 1st, 2002, 12:22 am

May 7th, 2012, 7:15 pm #5


Well, yes.....

And here's where we run into my limits of machining knowledge. didnt know you could use a deburring tool inside the bore..... And being inside the bore, I was always under the impression you need copious amounts of strong kung fu, and a healthy dose of black magic.... 


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the Lunatic Fringe of American Airgunning
Southwest Montana's headquarters for Airgunning Supremacy
Proud Sponsor of team_subsonic
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Joined: March 1st, 2002, 12:22 am

May 7th, 2012, 7:17 pm #6

big holes can cause the pellet to drag and shave off bits as crosses the hole. Need to revisit my DeLisle drawings.........

dr_subsonic's pneumatic research lab

the Lunatic Fringe of American Airgunning
Southwest Montana's headquarters for Airgunning Supremacy
Proud Sponsor of team_subsonic
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Joined: April 28th, 2010, 12:23 am

May 7th, 2012, 7:19 pm #7

Last edited by robnewyork on May 7th, 2012, 7:23 pm, edited 1 time in total.
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Joined: April 28th, 2010, 12:23 am

May 7th, 2012, 7:20 pm #8

Well, yes.....

And here's where we run into my limits of machining knowledge. didnt know you could use a deburring tool inside the bore..... And being inside the bore, I was always under the impression you need copious amounts of strong kung fu, and a healthy dose of black magic.... 


dr_subsonic's pneumatic research lab

the Lunatic Fringe of American Airgunning
Southwest Montana's headquarters for Airgunning Supremacy
Proud Sponsor of team_subsonic
Last edited by robnewyork on May 7th, 2012, 7:22 pm, edited 1 time in total.
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Joined: March 1st, 2002, 12:22 am

May 7th, 2012, 7:34 pm #9

but its probably oranges to apples cuz its PB technology developed by folks that know powder burners well, and have the tooling to do it right....

dr_subsonic's pneumatic research lab

the Lunatic Fringe of American Airgunning
Southwest Montana's headquarters for Airgunning Supremacy
Proud Sponsor of team_subsonic
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Joined: April 1st, 2009, 3:18 am

May 7th, 2012, 7:42 pm #10

....45cal pistol round firing, bolt action rifle scarcely used during WWII (only 220-250 originally made). Said rifle had a built in/on silencer. Full shroud, if you will.

http://www.youtube.com/watch?v=c22QPvsTGv8
<img src="http://www.google.com/imgres?imgurl<span class="link">http://www.rifleman.org.uk/Images/deLisle_drg1.gif" alt="[linked image]"></span>&imgrefurlhttp://www.rifleman.org.uk/The_DeLisle_carbine_main.htm&h=479&w=704&sz=42&tbnid=lC7Hx2LcT49_uM:&tbnh=82&tbnw=121&prev=/search%3Fq%3Dde%2Blisle%2Brifle%26tbm%3Disch%26tbo%3Du&zoom=1&q=de+lisle+rifle&docid=uYLRfkHv_7PXoM&hl=en&sa=X&ei=KCWoT4ebGoKqgwfWpvXeAQ&ved=0CG8Q9QEwBQ&dur=158

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