Please help - is this shotbun barrell ruined?

[BTin]

Hi,

I am new to guns, and don't know that much. I am new to the forum as well.

My grandfather had a Mossberg 500 for years without cleaning it, so he asked me to clean it. I was cleaning it when I noticed a bubble in the barrell. I used a bore brush to clean it, and it didn't change.

The bubble is on the top of the barrell in the picture that I tried to attach.

Is it ruined?

Thanks.

[WarHawk-AVG]

Looks like pitted rust...I doubt its ruined unless its near or in the chamber area

Pitting like that can weaken a shotgun barrel [it just depends on how deep the pitting is], I have fired many a shotgun that has had worse pitting than that

If the metal itself is bulged like there were two rounds fired [one got stuck in barrel then another fired behind it] then its a no go..but rust and pitting should be ok.

[BTin]

Looks like pitted rust...I doubt its ruined unless its near or in the chamber area

Pitting like that can weaken a shotgun barrel [it just depends on how deep the pitting is], I have fired many a shotgun that has had worse pitting than that

If the metal itself is bulged like there were two rounds fired [one got stuck in barrel then another fired behind it] then its a no go..but rust and pitting should be ok.

Thanks very much! It looks to be about 6 inches away from the receiver and the barrell is not bulged, it just looks to me like rust may have caused a bubble. I was surprised that a barrell brush didn't remove it though!

[MoJo]

Removal of rust from a gun's bore can be difficult. A shotgun barrel is probably the easiest. Saturate your barrel with a good penetrating oil Kroil is probably the best, brake fluid is a close second . Spray lubes like WD40 will work but they take longer. Let the penetrant soak for an hour or so and then scrub with a bore brush. If the rust spot doesn't break up and go away repeat the soak and scrub the bore with a bore brush wrapped with medium to fine steel wool 0 or 00 works well for this.

The "bubble" you are seeing is a lump of rust it won't affect the function or safety of your gun but, the pit left will trap fouling making cleaning more difficult.

[BTin]

Thanks so much for everyone's help!