View Full Version : Rough Spot in Rifle Bore

Barnacle Brad
January 22, 2013, 02:52 PM
I am cleaning my ot six after hunting season and feel a rough spot in my bore perhaps a couple inches after the chamber. After brushing, it could still be felt so I soaked a bore mop in Balistol and soaked overnight. This morning brushed again and swabbed. It FEELS worse!:eek:

Anyone ever see (or feel) this and should I be concerned?


James K
January 22, 2013, 03:44 PM
Can you find a gunsmith or someone else with a bore scope so you can actually look that the rough spot? If you can see into the bore, can you spot any roughness?

When you last fired the rifle, did you notice any problems?

It could be rust if the bore got wet or the gun was stored in a moist area. Of it could be fouling if you have been firing cast bullet loads. That is too far forward to be throat erosion, plus I doubt you have fired the rifle enough to worry about throat erosion.


January 22, 2013, 03:55 PM
What's an (ot six ) ???

Be Safe !!!

January 22, 2013, 04:08 PM
Caliber .30, Model 1906--- 30-06 :p

They talk funny in Wyoming !

James K
January 22, 2013, 04:25 PM
It is a dirty ot six; don't get it confused with the dirty-dirty, which is smaller.


January 22, 2013, 04:38 PM
They talk funny in Wyoming !
Well, they read funny, in Iowa. .... ;)

Ya know, most of the time, the only thing we have working for us, is a good sense of humor. ..... :)

Be Safe !!!

Barnacle Brad
January 22, 2013, 05:31 PM
Thought you guys had seen and heard everything, hahahaha.

Thanks Jim, as far as last shot it was on the money. I don't have any storage issues regarding dampness and I shoot jacketed bullets. If I noticed that spot last time I cleaned it, I don't remember.

It just seems weird and I guess the only way to get to the bottom of it is to run a scope in to look at it.

Thanks again for your thoughts Jim.

January 22, 2013, 06:49 PM
Could just be copper build-up. Most gun cleaners claim to remove copper, even when they don't do it very well. Ballistol could loosen the edges of the layers in a serious build up, so that it feels rougher on a patch. Read this article (http://www.boretech.com/docs/articles/precisionshooting_jan.pdf) as a starting point.

January 22, 2013, 06:58 PM
Did you pull the bolt, point the muzzle at a light and do a visual inspection?

What did you see??

I ran into the same thing with my son's AR-15 chambered in 6.5 Grendel. It wasn't shooting "right" last time at the range so I checked it out for him.

I was cleaning it for him and felt a restriction just ahead of the chamber when running a patch through the bore.

Pulled the bolt and there was this ugly looking black ring there- I thought something had torn up the rifling it was so thick.

Turns out it was a very hard to remove carbon ring- hardened...it took a lot of scrubbing/brushing with JB Bore Paste, and Carb-out, to get rid of most of it. I still see black discoloration, I think it's just the stainless steel discolored because the rifle is back to shooting sub-minute.

The location- just ahead of the chamber- suggests that to me... it'll be easy enough to see if that's the case.

Rainbow Demon
January 23, 2013, 02:38 PM
1903 barrels with excessive erosion can result in blown through jackets, leaving a ring of jacket metal stuck in the bore. Subsequent firing irons that ring of metal into the bore so its not always visible.
This sort of erosion was a serious problem with the .30 cartridge of 1903 or any .30-06 cartridge loaded with the early HiVel type double base powders with 30% or more nitroglycerine content.
They discontinued use of those powders for military ball, but some long range match shooters still prefered them despite having to discard a barrel after each season of competition.

At one time a stuck jacket removal tool was part of every cleaning kit, but when they switched to Pyro-Cellulose and Dupont MR or IMR powder they only issued a few of these tools per company.

If a blow jacket or a layer of thick jacket fouling prevented solvent from reaching bore steel very serious corrosion would develop under the fouling. When that metal fouling broke loose or dissolved a very rough spot would be left in the bore.

James K
January 23, 2013, 04:21 PM
I think a blown jacket with modern sporting ammo is pretty unlikely. More likely is that the rifle was stored where some teeny-tiny critters could get in the bore and build a happy homestead.


Barnacle Brad
January 24, 2013, 12:18 PM
Unclenick and Tobnpr - Thanks for your thoughts and after reading the article presented, I feel like the issue would be resolved if I try the products mentioned there.

The article, in fact was very enlightening and after researching the recommended products (Bore Tech Eliminator for copper fouling and Slip2000 for Carbon) the thing I come back to in my cleaning process was one particular patch.

It was after I had soaked the spot with Hoppes #9, the first patch I ran through came out with a greenish tint and my first thought was that it was from the bore brush. I now believe that the solvent had started working on a copper/carbon deposit.

So my intent is to purchase those copper and carbon cleaners as well as a 'Proof Positive Bore Jag' and go another round with her. I will post my results.

Thanks again!

Barnacle Brad
January 24, 2013, 12:27 PM
Just wanted to say - on the Slip2000 web site, they have some other products I was interested in for my BPC rifle shooting and maintenance. Check it out here:

January 24, 2013, 02:17 PM
Hoppe's will, very gradually, attack copper, so you are correct that the green you saw was that, but it's a piker compared to what Eliminator does. Run a patch in and let it sit just two minutes and push it out and it will be an very dark cobalt blue.

And there are still others that have appeared since the article was written or, at least, were not well known then. KG-12 is probably the best copper remover. It will take off more with one patch worth than any other. But it does not turn blue or green. It just gets a darker orange brown, so you need either a bore scope or Eliminator or some other color indicator to prove the copper is gone. KG-1 Carbon remover is also good. But Eliminator is still the best all-purpose cleaner, IME.

The Slip2000 works well and their synthetic gun oil is good for not burning down to become more carbon in the bore.

My favorite trick is to carry a small pump sprayer of Eliminator to the range, and as soon as I'm done and before the carbon has time to harden, I pump a couple of squirts into the chamber and let it run down to the muzzle. I then plug the muzzle and chamber and head home. When I get there, most everything patches out with just a few wet patch cycles with time to wait inbetween (usually just 5 minutes, but you can leave it much longer if you have other things to do; 20 minutes like in the article is fine, requires the fewest total patches, but is not as quick as several 5 minutes soaks if you are in a hurry to put the gun away).

Barnacle Brad
January 29, 2013, 06:50 PM
This may be posted in another thread, but I edited the text from http://home.comcast.net/~dsmjd/tux/dsmjd/tech/eds_red.htm and fixed typos and other errors.

Barnacle Brad
January 31, 2013, 07:05 PM
Ok - here it is:

After a few cleaning sessions over as many days, alternating between Hoppe's Benchrest #9 copper solvent and two different carbon removers, she is as clean as she is gonna get.

I have come to the conclusion that the rough spot I was feeling (and still do to some degree) is the gas port. I guess it should have occurred to me sooner, but I am glad to come to some conclusion at any rate. At least I can justify an end to the cleaning!

I am convinced also that there was a lot of carbon and copper build up around the gas port and all the cleaning I have done is well worth the effort. I have never had a problem cycling ammo in my Rem M742 and probably never will hereafter!


Lesson to me and others - posting your gun model is probably a good idea no matter what. Any of the experts may have pointed out the gas port as a possibility if I had thought it important to add my gun model at the very beginning of the thread.


Save your criticism for the Rem M742. I have had mine for a decade and have killed white tail, black tail, mule deer, antelope and other unfortunate critters without a hiccup. it's my meat gun - get over it!:D