Does oil in the bore prevent copper fouling?
 

I’ve never thought of this before, but have noticed something as a result of something unrelated.

With another dust up over barrel break in I thought I’d look at it more closely. I had a brand new barre, a bore scope so thought why not? The barrel as received from the gunsmith was cleaned, and oiled and put away. I use Eezox in the bore as it goes on wet, but is considered a dry lubricant. It is not supposed to have an effect on the fouling shot and my experience seems to bear this out. So my first shot in this break in process would have been over this synthetic oil.

The first shot produced some copper fouling in the front half of the bore increasing as it approached the muzzle. Not uncommon. And it cleaned up fairly easily. A few patches and good. This time I did not oil the bore. The bore was scoped to confirm this and then the next shot was fired.

This time the fouling was similar in placement but more of it with noticeably more at the muzzle. Cleanup was much more difficult and one land at the muzzle was particularly stubborn. Again, this is not uncommon, but we were progressing backwards. After cleaning I had the though of the oil and so put a light film of Eezox in the bore.

After the third shot, the fouling is again noticeably less, even than the first time, and clean up was easy.

Now none of this has any real scientific process, nor can any theory be proven. But, if copper atomizes in the bore, would it have less tendency to grab the metal if oiled, or if it’s washed in would the same principle apply?

It makes me wonder what effect this would have on accuracy? Less resistance would put a faster spin on the bullet I would think?

I'd be really interested in your further observations on this chuck. I don't have a bore scope to really check anything, so I have to just go by what's on my patches and how difficult or not cleaning is.

I did notice that when I switched to Lucas gun oil a few years back, that my cleanups have become faster and easier in general. It's just a subjective thing, but when you shoot 500 or more rounds with a pistol every week, and cleaning 3-6 different handguns, you tend to notice differences.

I do believe having a 'wet' barrel reduces fouling, but not sure how that impairs accuracy? Purely my subjective feeling on it. And I think that the quality of oil you use also has a bearing on it.

Does your point of impact change? How about velocity? Is it repeatable and consistent?

None of the above has been tested. It was not the intent of this experiment. However, Eezox does not affect velocity or POI in the many rifles I’ve used it in over the years. That’s why I and others use it. But again, this isn’t the point of this discussion.

So whats the point then

Of what?

So barrel break in can be more easily done without cleaning/copper removal but by instead oiling the bore?

Can someone remove this thread.

Let’s go back to discussing the 308 vs the 30-06.

Good idea

bullet can only spin as fast as the rifling twist dictates.
the number of revolutions it makes prior to hitting it's target or falling to the dirt may go up or down if the velocity goes up or down in relation to friction.

I know that any time I have cleaned up a bore, I make sure that the next shot gets shot out of a "wet" bore, I never did check to see if things were better or worse as far as copper fouling goes however, from a " wet" bore or a completely dry bore.

Cat

I usually do the shoot 1 clean 1 for the first 20 rounds on a new barrel. I run a wet patch of Microlon GunJuice through prior to each shot. I have no data whether this is actually helping with break in but it seems like the barrels clean up fairly easy.

I clean my rifles sometimes at the shooting range and in this case I do not use oil at all.
But after that I will usually shoot couple of rounds to foil the barrel , let it cool and shoot another 2-3 at 500 m to verify its a dead on at that distance.
Usually it is.

When I clean my rifles at home, then I use oil as it could be seating in the safe for couple of weeks or months before it gets used.

The POI from the oiled and "dry" bore would be a bit different for the first couple of shots but then it gets back to "normal" either way out of my experience.

I do not clean my rifles too often, only when accuracy goes down and with an "oiled " before shooting barrel, it seems like I can get more shoots out of it with a good accuracy then with a bore that was not lubricated.

S12

Makes sense it will foul less, the discussion moves to are you going to lube the bore between shots. Guys are trying the same idea by coating the bullets with various media. Ie moly etc

Never had a bore scope ... but my guess... as the bullet moves forward in the bore, it pushes the bulk of any oil present ahead of it, resulting in a buildup which results in increased pressure. There would be very little lube left to adhere to the bore towards the shank end of the bullet so the jacket would start to shed copper. It would be logical to assume more copper would be shed in a “rough” bore.
Now, back to the effect on the “wet” shot which may have a different POI down range due to a different velocity related to the pressure buildup. It follows that subsequent “dry” shots would be relatively consistent, at least until the buildup of copper results in change. Copper adheres to copper more than copper adheres to steel ... but that is another issue.
Well, right or wrong, that’s my theory:)

Please let’s not go there.

Makes sense to me!
Great thread! Less cleaning more blasting!

A couple of years back I was reading a thread on how much difference in accuracy that cleaning the fouling out completely can make with cast bullets. I did notice a slight difference at 100 yards but not significantly. Cast always hits 1.5 lower than brass using my 45/70

Maybe it’s just increased powder. Dunno

I had seen that recently and was kind of curious about it. I can see it being beneficial for co.letition shooters to try and keep the rifles cleaner longer after the fouling shots. Not sure if it would benefit a hunter. I still have more reading to.do. I did read about one where you put the bullets in to a tumbler before you press them. At least I think it was.


Chuck may not have tested velocities or accuracy effects with his thought on this. Maybe it's been done before, maybe not. But it wouldn't hurt for someone to try again. I could see velocities and accuracy going down from one standpoint, but on the other hand I could see velocity going up.

A number of years back I came across a couple of cans of spray on Moly. I did some testing with one of my 308s for velocity/ accuracy ( sadly I did not own a borescope at the time or I would have used it to check fouling as well) my load was tested over a chrony and had a mv of 2586 with an SD of 6 targets where shot at 200 yds. I had 8 3 shot groups right around 1.50" and 2 opened up to 2.25" ( I thought they were shooter error) prone on bipod. These groups gave me a mean to average against.
My first try was coating the barrel as directed and I was going to 5 3 shot groups. Same distance over the crony
First group was 2655 fps average with a 8 SD (1.56")
Second group was 2598 average with a 12 SD ( 2.64")
Third group went back to 2586 mv and SD of 7 ( 1.58")

Obviously the Moly was shot out
My next test was 3 3 shot groups but reapplying every three shots
First group was 2663 avg 5 SD ( 1.43")
Second group was 2674 avg 9 SD ( 1.79")
Third group was 2678 avg 11 SD ( 1.82")

My take away was Moly worked but had to be reapplyied about every 4-6 shots for consistency but unless there was exactly the same amount in the barrel shot to shot SD MV and accuracy varied. I did not have any way to check fouling, But.... I do still have an old can full of moly still on my bench....might be time for another test.

The old muzzle loader mountain men types talked about seasoning a bore, much like you would with a cast iron fry pan. Repeated lubrication between shots to condition the bores surface to reduce fouling.

I think what chuck is observing here is akin to this but with modern cartridges.

I only borrow Bushrat’s borescope at his house, but having broken in a few barrels through the years, I can attest to the simple fact that the first round through a brand new barrel takes what it takes to remove all signs of fouling as observed by the cleaning patches. Typically the second shot takes far less time and patches to get to the same state as after the first shot often on the order of 50% less. By the third shot, the amount of time and subsequent patches is perhaps 25% to 10% of that as taken after the first shot. I do run a slightly moistened patch with some gun oil as my second last patch while doing this, the last patch is a dry patch always.

Maybe I am seasoning the bore as much as I am breaking it in?

Shot four with Eezox in the bore shows zero copper fouling. Not sure if I want to shoot it dry next time to see if that changes anything.

I agree. Any liquid in the bore would create a "pressure wave" ahead of the bullet as there is nowhere else for it to escape. Any residue that may be left in the bore behind the bullet, with the exception of a metal, would be burnt off.. as it's flash point is normally much less than the temp of of the burning powder and subsequent gases. As for oil remaining in the bore after a shot, don't believe it.

When I mentioned a "wet" bore, I meant that there is no copper cleaner left because I patch it out, run a soaked rag of G96 through , then a loose dry patch that a removes the excess oil, as opposed to a completely dry bore .
There is still a microscopic film left in the bore , that is all.
Cat

I agree, lubricant may help keep the first round from fouling on a dry bare bore, but it's burned off with the first shot, now the bore is coated with powder fouling, carbon fouling, copper and residues from all three which all act as a dry lubricant for subsequent shots. The amount of shots before this fouling needs removed varies on many fronts, amount of powder burned, type of powder, completeness of burn, how hot it is burning, how much carbon and powder fouling it produces, type of barrel steel, properties of the bores surface, type of alloy of the projectile. These are just a few factors involved in fouling. Far from an exact science.

I did notice that the first shot out of a freshly cleaned barrel does not group as well in some rifles, but it isn't noticeable with other rifles. Watching the chronograph, the first shot out of a clean barrel, is sometimes slightly lower out of a freshly cleaned barrel, how much lower depends on the rifle.

I put through the chrony it once and it was a 110 f.s drop in a speed for a first shot out of 'oiled" barrel .
It was 2 1/2 inches lower at 300m also .
Less pressure due to the oil does those things I guess.

S12

I always put two wet patches with g96 spray down the tube prior to cleaning and after followed with one dry patch . If I haven't shot it for a few months I repeat . Before I go shoot it I always run a dry patch down the tube . I just think that a dry clean shiny bore is better for no other reason than I think it is ... prove me wrong !!

a major cause of fouling is created with the chamber reamer, right where the reamer cuts an angled ramp out of the rifling lands. this is the part where a rough surface will do the most damage to a bullet jacket. under a borescope you can watch this section of the lands get smoother with every shot. if the reamer has a rough leade section, this will add to a premature copper fouling condition. oil or other lubricants and coatings won't be enough to protect the bullet jacket from a rough steel surface. usually takes about 20-50 rounds to get this smoothed out, depending on initial surface condition. very hard to diagnose fouling issues without a borescope IMO.

It seems to shoot. These are shots 11, 12, and 13 from this barrel. This was not a group shooting exercise, but merely establishing a velocity base line. But I’ll take it. I have some additional thoughts on barrel break in, but for now process complete.

https://i.imgur.com/K9Dhg40.jpg
https://i.imgur.com/enFEl6r.jpg