06 May 2015
@ 03:35 am (GMT)
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Nathan Foster
Re: Sweets7.62
Hi Mario, on a chrome moly bore, the long term effect would be corrosion but that goes for a range of things that may come into contact with the bore. For example, you can wash a .303 barrel with boiling water, but leave water for any length of time and oxidation will set in.
Trouble is, sometimes you have no choice but to leave the Sweets to sit. This could be 30 minutes or up to an hour or two. If the bore has stubborn copper fouling, the fouling has to be removed one way or another. Mechanical etching with a bronze brush certainly helps speed up copper removal.
Polished stainless is certainly less of an issue. You can put a dribble on a high carbon stainless kitchen knife, leave it to sit for half a day and see for yourself.
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06 May 2015
@ 03:45 am (GMT)
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Mario Ribicic
Re: Sweets7.62
Thanks Nathan.
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06 May 2015
@ 11:38 am (GMT)
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deerndingo
Re: Sweets7.62
It has been explained to me that sweets uses ammonia as its copper removal agent. This evaporates quite quickly in contact with air. When it evaporates it also removes all oils n other agents with it. This apparently exposes the steel to the atmosphere and promotes corrosion. The other aspect of this is that leaving a wipe of it from a jag results in the effective component of it evaporating after so many minutes. Hence, there is little value in leaving it in the bore for very long anyway.
I haven't tested this. I'm no scientist. This is just what Uncle Nick said one time in one of his articles.
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06 May 2015
@ 12:23 pm (GMT)
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Thomas Pavelka
Re: Sweets7.62
I've used Sweets for, well a long long time now. For me, the 10 minute rule works. I first clean the bore with something like Hoppes or Bore shine. Then dry it out good. THEN I jag a patch wetted with Sweets and place the rifle muzzle end down. After 10 minutes I run a fresh patch through. Depending on the "Blue" amount I then hit it again with another Sweets jagged patch. By the time the third regiment is up the last patch out is whistling clean. Never have been a believer in the bronze brushes and the patch thing works for me. Too, Sweets will eat bronze brushes over time.
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07 May 2015
@ 09:22 am (GMT)
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deerndingo
Re: Sweets7.62
I use a nylon brush. It loads up the bore with more product. To each their own.
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07 May 2015
@ 08:53 pm (GMT)
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Nathan Foster
Re: Sweets7.62
Uncle Nick would know (Nick Harvey).
OK, just a bit more to add to this thread.
The above photo shows a Sako suffering from severe copper fouling on the lands. Other rifles may show the same in the grooves. This coating is in essence fused to the bore. Think of it as being pretty much guilded / braised in place.
If we put Sweets through this bore and leave it for an hour, the Sweets will have worked on the top most layer, the reaction dies off, then no further copper removal occurs. So leaving it sit is not ideal.
So, in order to cut through this layer, we need mechanical etching from a bronze brush, plus regular doses of fresh Sweets etc. I do not simply leave the bore to sit, slowly corroding away.
"But what if I was to use KG-12 or Eliminator?"
Well- Its the same deal. These fair no better when it comes to a braised on layer such as this. I have also noticed with KG-12, that if you walk away and come back later- and if it is a hot day, the KG-12 will turn to varnish. If you do not break this varnish layer up with a bronze brush, then you will be in real trouble next time you go to shoot. That said, BoreTech is advertised as being OK for lengthy soaking periods (even if the action / reaction is no longer effective).
The trick is to stay close to the rifle, work on copper removal for as long as it takes, then work on rectifying the causes of severe copper fouling.
Time can be a great issue. The reality is, as much as it would be nice to stand at the ready and pump fresh solvent through the problematic bore every 10 minutes, we may have a very busy schedule following our hunt / range day,...a work day ahead of us...kids need to be taken to sports etc etc. In other words, there are times when things don't go to plan and we don't follow an ideal method.
I can tell you that from my talks with customers over the years, that there have been folk who have left solvents in the bore for whole days. One target shooter would leave Sweets in his heavy fouling stainless bore from Sunday afternoon until the following Saturday morning.
More thoughts.
You would expect that a person in my position must deal with nice rifles. Well, that just isn't the case. People don't send me good rifles (unless its a custom job). I get to see all the problem rifles. Being willing to work on problem rifles is what got me here. That and having to buy some real dogs ourselves in order to be able to afford all the testing we wanted to perform.
There are times (such as the above pictured rifle) when you get to a point where the manufacturers recommendations mean very little in light of the job at hand. It is not as if you can make the problem bore any worse than it already is. The same goes for polishing routines.
While one gunsmith may sneer at DIY polishing methods (black arts should be left to the wizzards, not you small people who can't be trusted to tie a shoe lace, oh look I just farted and it smells like Lavender), well its all the same. When a bore is causing such problems and shooting 3-5" groups after it fouls, it is not going to magically rectify itself or come clean with a bottle of smug.
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08 May 2015
@ 12:06 am (GMT)
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Martin Taylor
Re: Sweets7.62
Have to say, if l just soaked 7.62 in my 300 Rem to remove the copper from my Berger training load l would never get to shoot it! hahahaa ever, well not accurately anyway.
It would take that long to remove the fouling, l have to scrub with a bronze brush between soaks and it still takes a long time. My Rem 308 & Tikkas will clean with a soak but my 9.3 needs a scrub with a nylon brush. Howas need a scrub with soaks as well.
So guess it's back to barrels having a personality of their own that you need to work with using lapping etc.
Oh damn this bloody shoe lace, zips next time!
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