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Kibby
03-30-2010, 06:00 AM
I've found it necessary to enlarge the gas port holes in a Remington 1100 barrel. My question to you, my astute colleagues, is how would I deburr the port holes inside the barrel? Right off, I am thinking a brake hone or even some 600grit sandpaper on a rod, spun by a drill. Any thoughts?

Ron of Va
03-30-2010, 07:12 AM
See pages 240-248, you will find something that will work.
http://www.use-enco.com/CGI/INPDFF?PMPAGE=240&PMCTLG=00

Kibby
03-30-2010, 06:26 PM
Thanks Ron, but I saw nothing there that would help me to deburr a hole inside the barrel.

What about something like this:

http://www.mytoolstore.com/kd/kdbrak08.html

What do real gunsmiths use?

Forestgnome
03-30-2010, 07:16 PM
I asked that same question on "the other site". Some good info.

http://www.practicalmachinist.com/vb/gunsmithing/deburring-gas-ports-169891/

Ron of Va
03-30-2010, 07:45 PM
Thanks Ron, but I saw nothing there that would help me to deburr a hole inside the barrel.

What about something like this:

http://www.mytoolstore.com/kd/kdbrak08.html

What do real gunsmiths use?

Kibby,
I own and have built integrally suppressed 10/22’s. Those require porting the barrel, and I have done a number of them. One of the class III weapons builders I used before I began building my own, turned me on to the Cogsdill Burraway tool here: http://www.use-enco.com/CGI/INSRIT?PARTPG=INLMKD&PMPXNO=16719063&PMAKA=619-1310
It can be obtained in different sizes to suit your needs, and can be seen on page 248 of the link I posted. If the tool bottoms out, the end can actually be trimmed back so it will go deeper in a blind hole. But many of the de-burring tools listed in the link I gave you will do the inside of a hole a lot cheaper than the Cogsdill.

There are some professional builders of AR-15’s that post on the gunsmithing forum at BenchrestCentral.com. If you posted your question there, maybe one of them will tell you what they use.

One of the things I learned about drilling a port is that you should drill it in 3-4 steps to minimize the burrs. The final size should only be about .002”-.003” larger than the step before it. That way practically no burr will be there to deal with.

I hope this helps.

Kibby
03-31-2010, 05:51 AM
How does that burraway tool work, Ron? Does that triangular end rotate? I guess I am not picturing it.

Also, if I drill the gas ports in small steps, could I simply use a reamer for the last step? Perhaps the secret is in using sharp drills and then a nice sharp reamer at the end?

Kibby
03-31-2010, 05:55 AM
Holy cow! I just went to the Cogsdill site and saw a video of how that worked. I think that's do the trick, but how will I get my shiny finish back inside the bore? Is a shiny finish necessary inside a shotgun barrel? All I will ever use in this particular gun is 00 if that makes any difference.

Ron of Va
03-31-2010, 06:03 AM
The blade in the Cogsdill tool is spring loaded, but can be locked in place after it expands on the inside of the hole. You twist the tool back and forth to de-burr, and then unlock the blade so it will fold back inside the holder for removal. It is depicted in the link I posted.

Drilling is small steps with sharp drill bits helps a lot, and a reamer on the final pass would be fine.

I wouldn’t worry about a shinny finish or using 00 buckshot. All the shotgun shells I shoot have the shot enclosed in a plastic sleeve. I don’t think lead touches the sides of the barrel anymore.

Highpower
03-31-2010, 08:57 AM
Holy cow! I just went to the Cogsdill site and saw a video of how that worked. I think that's do the trick, but how will I get my shiny finish back inside the bore? Is a shiny finish necessary inside a shotgun barrel? All I will ever use in this particular gun is 00 if that makes any difference.Just to be clear.....
You do realize that Ron is talking about inserting this tool through the PORTS and not down the muzzle of the barrel right?

It sound like you are talking about honing out the bore, which would remove the choke (unless cyl. bore) from your barrel. Not sure you guys are on the same page here. :o

CLARKMAG
03-31-2010, 11:20 AM
Low Price: $47.98 ea

Cogsdill tools were nearly free when there was a Boeing surplus store:(

I am getting ready to drill a gas hole myself.
The rifling makes the de burring tool problematic.

http://www.benchrest.com/forums/showthread.php?t=66814

I am going to drill undersize and then ream the hole to .093".
http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=2048588&PMT4NO=82792361

I always liked reamed holes better than drilled holes; rounder, smoother, more precise diameter.

Highpower
03-31-2010, 01:02 PM
The rifling makes the de burring tool problematic.
The original post concerns a Remington 1100 shotgun....

mf205i
03-31-2010, 01:26 PM
I use a soft finishing nail with the head ground like a Martini glass. Chuck the nail in a small die grinder, charge it with abrasive paste, insert it through the port and have at it.
I find it troubling that you need to open the ports for 00buck. Remington is very generous with the port size. For guns that see a lot of heavy loads I have peened ports closed to protect the gun from battering. I would investigate further before you open the ports. Is the O ring in good shape?
Mike

CLARKMAG
03-31-2010, 04:20 PM
The original post concerns a Remington 1100 shotgun....

Me thinks thou....

Kibby
03-31-2010, 06:07 PM
Just to be clear.....
You do realize that Ron is talking about inserting this tool through the PORTS and not down the muzzle of the barrel right?

OMG you are right, I WAS thinking of doing it down the bore. What a dummy I am. :eek: Criminy, if thats all I need to do, I can easily make a tool to do this.

Kibby
03-31-2010, 06:14 PM
I find it troubling that you need to open the ports for 00buck.
Mike

I was stating that I was only going to run 00 through the gun and whether that made a difference.

The real reason I need to open the gas holes a bit is that fact that I lopped almost a foot off the barrel, which was originally 30". The gun is otherwise completely refurbed, and rebuilt with new parts. Here's a pic:

http://i485.photobucket.com/albums/rr220/pallymcgee/Rem1100007.jpg

It runs, but is kind of limp when it loads and ejects. I'm thinking gas ports resized and a new recoil spring and it'll be fine. Oh by the way, the finish is KG Gunkote. Very tough stuff. Once baked, its as tough as any parkerizing job I have ever done. The color is called Milspec OD Gray.

Kibby
03-31-2010, 06:17 PM
Don't beat me up about the lack of extension-tube clamp. Its in the mail! :p

Highpower
04-01-2010, 09:16 AM
Wow. Very nice job on the finish. Looks perfect. :)

Toolguy
04-01-2010, 01:37 PM
The best way to do holes like that is with a ball end mill. The end mill makes a very clean hole with thin, feathery burrs if any, then its a simple matter to run a cylinder hone down the bore to knock those off. A stainless cleaning brush works fine too. Use a new sharp end mill.

38_Cal
04-01-2010, 05:16 PM
Toolguy, the Remington shotguns vary in gas port sizes from about .125" down to drill bit size 53 (.060"), depending on model, gauge, barrel length, standard or magnum chamber, presence or absence of muzzle brake, recoil reducer or recoil porting. There's a list on James Wisner's site here: http://www.wisnersinc.com/additional_info/Remington58_1100.htm.

David

Kibby
04-01-2010, 06:20 PM
The best way to do holes like that is with a ball end mill. The end mill makes a very clean hole with thin, feathery burrs if any, then its a simple matter to run a cylinder hone down the bore to knock those off. A stainless cleaning brush works fine too. Use a new sharp end mill.

Like a brake cylinder hone? That would leave a nice cross-hatched finish in the bore I reckon. I have thought about this as a way to renew the bore. Is the surface of the bore ID an important performance feature? How about lets say a 600 grit finish? Do you think that would be okay? Like I said, this'll be a gun for home defense - not hunting. Buckshot would be the load of choice, so I mention that again because I would be interested to learn from you guys if the ID finish is all that imoprtant. Do you think a 600 grit finish would create drag on the wad?

Toolguy
04-01-2010, 07:55 PM
A 400 or 600 grit finish will be plenty good. That will give a very smooth bore. If you want, you can finish up with a scotchbrite pad wrapped around an old cleaning brush and run it with a drill motor on a short section of cleaning rod. You can cut the scotchbrite pad to the desired size with a pair of scissors.

Kibby
04-02-2010, 04:30 AM
A 400 or 600 grit finish will be plenty good. That will give a very smooth bore. If you want, you can finish up with a scotchbrite pad wrapped around an old cleaning brush and run it with a drill motor on a short section of cleaning rod. You can cut the scotchbrite pad to the desired size with a pair of scissors.

That is precisely what I was thinking!