I am a fan of Dyna-Tek Bore Coat. I have used it on over a dozen rifles that I shoot with some regularity, with good results. I have found no down-side to this product. I have seen noticeable improvement in reduced fouling in brand-new rifles as well as well-pitted bores over one hundred years old.
I just discussed my thoughts on getting the best results with DBC on another thread regarding a new rifle. That posting turned into an essay on DBC, so I will expand on that here in a thread actually discussing Dyna-Tek Bore Coat.
I just purchased a new Bergara B14 rifle in 6.5 Creedmore. The borescope revealed an exceptionally smooth leade/throat area where the chamber transitions to the rifling. Our own MuleDeer has opined that this is the primary area of a new rifle barrel that may actually benefit from some breaking-in.
The chambering reamer may often leave significant tool marks and tiny burrs, in this transition area. Often on factory rifles the chamber is not absolutely perfectly aligned with the center of the bore. The chamber may be ever so slightly offset, or it may be at a very slight angle to the bore. In the past these problems were best avoided by using custom barrels from quality makers.
The borescope reveals these problems. It also is the only way I have found to know for sure when a barrel is absolutely clean, which is seldom really necessary, except when preparing to apply the DBC treatment.
I believe that fairly good results, at least noticeable improvement, can be obtained with DBC even if the barrel is not completely free of all the copper and the very hard, old, thin carbon layer. But the very best results will be obtained with a completely clean, bright, shiny bore achieved with generous use of JB Bore Paste on a large patch wrapped around an undersized bore brush (many, many strokes) alternated with a good copper remover, like KG-12 and the Montana X-Treme products. Some people prefer the electrical Foul-Out process, which is a viable alternative. I have no personal experience with the Foul-Out process.
Some of the best products are safe to use for overnight soakings with no barrel damage, which reduces the workload considerably if you are not in a hurry. Wipe-Out, Patch-Out, and the Montana X-Treme products are safe. Some other products can etch or pit the bore if left in overnight, so read the fine print on the labels when in doubt.
A badly pitted bore can never be made completely clean and patches will come out dark forever due to the old grime down in the pits below the surface. But the grime down in the pits doesn't really matter. If the copper and carbon are removed from the upper surface, where the bullet actually rides, and microscopic imperfections are smoothed out, the DBC will do its job. The surface is smoother and copper fouling is reduced from then on.
I consider the pitted bore to be sort of "sealed" now by the DBC. As in a clean bore, carbon will still accumulate, but very little copper. Badly pitted bores almost always shoot better with a good bit of carbon fouling than they do right after a good cleaning. It frequently takes a dozen shots or more to get the pitted barrel back to its accuracy potential, which is often surprisingly good, in spite of how bad the bore may look. From then on I do very little cleaning of that pitted bore.
Back to the cleaning of a good bore, with a normal accumulation of copper. The initial one third of the overall cleaning effort gets out two thirds of the copper. Sometimes the removal of the last twenty percent takes as much work as it took to remove the first eighty percent. Even after it is difficult to get any blue on the patch there can still be traces of copper in the bore.
Without the availability of a borescope, I can only advise that you keep cleaning for a while longer even after you are sure the bore is copper-free.
And now back to my new rifle:
I got the B14 Timber, 6.5 Creedmore, walnut-stocked with cheekpiece. Once it arrived at my home I scrubbed the factory-supplied traces of copper (from the proof load and any additional test rounds that the factory used) out of the barrel with JB Paste until the bore shined and then applied the Dyna Bore Coat.
Yesterday I fired the ten curing rounds and got the scope adjusted to near a 100 yard zero at the same time. As with past rifles, the curing rounds don't produce a very good group.
Today I cleaned the barrel by first removing the over-night soak of Wipe-Out foam, then going after the traces of copper with KG-12 and Montana X-Treme. The borescope told me when the last trace of copper was gone.
The bright shine in the bore produced by the JB Paste is now replaced by a somewhat darker, duller appearance that is characteristic of a DBC treated bore.
In my opinion, this thorough cleaning of the bore (but without abrasives) after the initial 8-10 curing shots is important to help get a consistent coating spread over the entire surface of the bore.
The initial curing shot always leaves some copper fouling, as does each subsequent curing shot. It is likely that this copper fouling will block those areas covered by the copper from developing complete coverage of the cured ceramic layer that we desire.
It is common experience that the first bore cleaning after the curing shots shows almost no reduction in cleaning effort required, or reduction in fouling. But then there is a very significant reduction in fouling for the next two or three cleanings and then fouling stabilizes at the new-normal state of reduced bore fouling compared to the pre-treatment level. From that point on we enjoy the benefit of the product: reduced fouling and easier cleaning, less often.
I believe this shows that curing of the DBC treatment is still continuing to take place, producing an even coating to the entire surface of the bore, for the first few dozen rounds fired through the bore, possibly aided by the next two or three cleanings of the bore. High temperature and pressure is what is doing the "curing".
I suspect that any copper fouling from the initial curing shots that is not removed during the first cleaning after initial curing may result in incomplete coverage of the ceramic coating within the bore.
This may be the cause for some few first-time DBC users concluding that the treatment didn't work very well for their rifle, or why an occasional rifle may need a follow-up treatment to get satisfactory results. I have yet to feel the need for a second treatment on any of my rifles, though the end result does seem to vary some from rifle to rifle. I have yet to see a rifle that didn't improve from the application of DBC.
For those reasons I try to do a very good cleaning of the barrel for the first couple of cleanings after treating with DBC, and I have always gotten good results.
I did not hesitate to treat this brand new Bergara barrel because close inspection with the borescope showed a high level of finish quality. No flaws or obvious tool marks were found and the leade area was very clean and smooth. A very tight patch run down the barrel showed no change in drag from end-to-end, indicating consistent dimension.
Some folks advocate breaking in a barrel before applying the DBC. In the past I have waited until after the first few dozen shots and a few good cleanings before applying the DBC. This is the first factory-virgin barrel I have treated, for the reasons stated. Whether it really makes any difference, I don't know.
This has been my experience with DBC to this point. I am sure others have more experience than I do, and of course, everyone's mileage may vary. Wishing good results to all.
Last edited by nifty-two-fifty; 02/07/16.
