hole in barrel question

[FLINT]

Hi all,

I've been working on a shotgun project lately. its a smooth bore slug gun and came with rifle sights.

The front sight was held on with a single 6-48 screw - and there was a hole drilled and tapped directly into the barrel so that there was just the tiniest hole where the drill bit must have just peeked through the barrel.

However, when I installed a new/different front sight on it, the front sight screw broke the hole through the rest of the way.

My question is: Is this bad? Will it negatively affect slug accuracy? Is there anything I should do? I think it broke through fairly clean, but should I run some fine steel wool around just to make sure things are smoothed out?

I've already shortened the screw so it does not stick down into the barrel now - so the screw isn't an issue, I'm just worried about the hole. Thanks!

[Griff]

If it were me, I'd want the screw flush with the inside of the barrel, vs. leaving any gap for debris to accumulate in.

[Chuck 100 yd]

What Griff said +1
Years ago I sent a Rem. 870 20 ga. barrel off to a guy to have it shortened to 21" and choke tubes installed. When he drilled the rib to install the front sight he drilled all the way through not only the top of the barrel but the bottom of the barrel too.

The choke tube installation was done very nice and it shoots well so I got over it and still today don`t know what he was thinking.

I would install that front sight and file the screw smooth with the inside of the barrel if it sticks through. No problem.
Here is my 20 with the extra hole in the barrel.

Don`t have a picture of the hole though. It is covered by the choke tube so no problem. Good place to squirt a drop of oil in on the threads now and then. Maybe that it what he did it for???

[damienph]

Chuck,

He probably meant to install a grease zerk so that you wouldn't have to oil the choke but could give it a little grease now and then.

[Chuck 100 yd]

Dang, I never thought of that!!

[sore shoulder]

I'm just here to say the title made me laugh thinking about the bore being the hole.

[FLINT]

What Griff said +1

I would install that front sight and file the screw smooth with the inside of the barrel if it sticks through. No problem.

how do you do that? do you mean slowly file down a screw outside of the barrel until it gets perfect when you screw it in,

or screw it in and then file it down inside the barrel until it is perfect?

if the later, how do you file down a screw inside a barrel without scratching up the barrel?

maybe I should just cut an inch off the barrel and remove the hole altogether (half kidding, half not). shouldn't matter since its a cylinder bore gun right

[Mike Hunter]

When working on guns, you always work on the leas expensive part or easiest to replace part first.

Now with that said, I would work on the front sight first. Screw the bead into the barrel, and then measure how much is protruding into the barrel and remove that amount from the threaded end.

There are a couple of ways to get a good measurement: one is to unscrew the sight just enough so that there is nothing protruding into the barrel. Then take a feeler gauge and measure the gap between the base of the sight and the barrel.


Another way would be to count the number of threads entering the barrel, and then remove that many threads.


V/R

Mike

[piller]

I have only done it once, and I did it the way Mike Hunter suggests. I understand that he has done it a bunch more times than I have, so it sort of makes me feel good that I did it the way a professional would.

[FLINT]

ok, great, thanks, I'll give that a try.

once its in there, should I try to polish or buff anything with steel wool or a felt bit on a dremmel or anything?

[Sixgun]

I'd just run a gas tube from the hole to the action and make it a full auto.

Na! Don't worry 'bout it. Like Griif said, make it flush.---------6

[Tycer]

If there are any burrs protruding into the barrel they should be removed. A fine stone or crocus cloth would work.

[Chuck 100 yd]

FLINT , I would just use one of my half round jewelers files to do it while it is in the barrel. It should be smooth with the interior of the barrel. Now if your barrel has screw in choke tubes that would require a different approach as the tube threads are very fine and easily damaged.
Not a big deal either way.

[mikld]

I looked at a"gunsmithing" video the other day (I was curious about rifle sights on a shotgun) and the feller doing the job drilled all the way through for installing a bead front sight. Yep drilled and tapped all the way through...

[Chuck 100 yd]

Shotgun barrels are so thin it is impossible to get enough threads in there to hold a sight so they drill through to get maximum thread engagement and just adjust the length of the threaded stub on the sight so in don`t protrude into the bore. Many shotgun sights are press fitted and then trimmed on the inside of the bore.

[FLINT]

Thanks, that is good to know

my shotgun barrel is definitely a little thicker than most barrels - its a non-removable slug barrel.

i'll see how close i can get a screw to being flush with the inside of the barrel - i'm not going to try filing it down from the inside - i'm sure I would scratch the heck out of the barrel