doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Barrel dents - how much to tolerate?

I have a nice engraved Lefever 16g that has a very slight dent in the right tube. I have not shot it yet but have to assume that it has been shot like it is. It gives me pause though and I wonder how much of a dent can a barrel have and still be safely shot? I do have a 12g dent raiser but not one in 16g and would fix this before shooting if I did have one. Can it be fixed with another method such as a well greased polished steel slug of the correct size driven through? Thanks for your responses!

I'd use brass or cast lead before steel - less likely to scratch.

I have always used an adjustable plug that you tighten slightly under the dent, then peen hundreds and hundreds of times lightly using a very small brass hammer or, better yet IMO, a brass round rod of about 1/2"-5/8" diameter with a concave filed into one end that will radius the outside of the barrel. I make the radius slightly larger than the barrel O.D. so that no edge actually contacts the barrel. Then, use a very small ball peen to tap the rod (punch). The barrels are rested on several bags of lead shot, nestled into them so that there is no movement while peening.

I find I get better control like this than with using a brass hammer alone. The dent will slowly raise while you peen over it, and you tighten the plug a little more. Continue until the dent is gone. Then, clean up the brass markings on the blue and touch up the blue at that tiny spot if necessary.

Never have had the opportunity to use a hydraulic dent raiser, but understand that they have so much power that one must be extremely careful not to cause a bulge. I just feel I have much more control the way I do it, but it is a slow process.

SRH

I have made a number of steel plugs that I made to the bore size and rounded and polished the nose on, greased and drove them under some good sized dents. Then of course, tapped the dent out.

A "slight dent" is not a safety issue.

How much to tolerate is up to you. If it is a very small dent, then you can leave it alone.
For removing dents, it is important to know the bore size. I have made aluminum plugs in 10 ga. 12 ga. and 16 ga. that are in .002 increments. I insert them into the bore to find the size up to the dent. I then make a steel plug that is .002 smaller than bore and tapered to slide under dent. I then lightly heat the area and will then tap the plug so that it is now tight and then use either a brass flat head hammer if it is a large dent, or a flat head hard plastic one. I then tap the steel plug more and keep doing so until plug slides past dent.

This plug gage is for a 10 ga. that has a bore of .775.





This barrel was ready for rusting/etching, and sometimes if the bluing is good and the dent is small, you can get away with not re-bluing whole barrel.

If you really want to avoid blueing and the blueing is in good shape at the dent, a piece of the thin mylar packing tape over the dent will protect the blueing. Then use a freshly polished steel hammer to tap the dent out. Using the tape will require you to hit the barrel harder to get the same effect as without tape, but it will also protect from marking the surface. It really works well.

I got the idea from aircraft rivet tape where mylar tape is used to hold a line of rivets and protect the skin when installing flush rivets.

Thanks for the responses! While the dent is rather small, I think I'll make some polished steel slugs to take them out. I will not mess with the blueing though - there is enough wear on the gun already and one more spot will not hurt the appearance to any degree.
Thanks again!

While I haven't attempted any repair yet, I was thinking about using pin gauges. I have a cheap Chinese set and they are in .001" increments from .060" to .750". I'll start with one that looks like it will slip past the dent and then go up from there in .001" steps. I may have to polish the leading edges but that is a lot easier than turning and polishing a whole plug!

Gazz
Pin gauges are perfect for the job.

I've used my friend's cheap set and simply rounded one end and polished that radius, grease it, and drive it under the dent, then tap away. I would advise against using a significantly undersize plug as you may end up printing an edge or tigher radius on the opposite side. I've alway used a matched size plug to the bore and drove it under with grease on it in one shot. The barrels are much softer than most people think. Go for it.

Make sure the nose radius is generous, like a 1/4" radius.