The Full Monty Barrel Prep!

[crowski]

I just happen to have a old shuffleboard, I’m using it for storing gun stuff till my room is done. Away the wax is actually minuscule balls. The rocks roll over the wax which looks more like sand.

Now I specialized in hockey skates which has the same theory. Less friction the faster you go. The shallower your hollow (your sharpening) the faster you go and you get an easier glide . Also a polished surface is far better than a rougher cut. Night and day difference. Crow 

 

[heavy-impact]

You don't want a mirror finish because it's too much surface area and causes more friction.

Please elaborate because this logic does not compute... a surface that is smooth and polished has more friction than a surface that is rough, unrefined, or textured?

I didn't say not to polish, just don't over polish because a mirror finish will create more friction and fouling and usually hurts accuracy.

All barrel manufacturers will tell you this. Here's a thread from a PB forum that covers the subject fairly well. https://forum.accurateshooter.com/threads/can-you-over-polish-the-bore-of-a-barrel.4007722/

I prefer to smooth out any rough spots and treat the bore with Dow Corning Molykote M77 now and then.

 

[Matt247365]

You don't want a mirror finish because it's too much surface area and causes more friction.

Please elaborate because this logic does not compute... a surface that is smooth and polished has more friction than a surface that is rough, unrefined, or textured?

I didn't say not to polish, just don't over polish because a mirror finish will create more friction and fouling and usually hurts accuracy.

All barrel manufacturers will tell you this. Here's a thread from a PB forum that covers the subject fairly well. https://forum.accurateshooter.com/threads/can-you-over-polish-the-bore-of-a-barrel.4007722/

I prefer to smooth out any rough spots and treat the bore with Dow Corning Molykote M77 now and then.

Wonder if it's kinda like this...

https://youtu.be/2lOOl3VxOtE

 

[crowski]

I’m not in any way an authority on air guns, I shouldn’t of piped in. I got into the friction part of my business 25 yrs. ago. Déjà vu. Made a massive difference. Friction seams to be the common denominator for a lot of problems, Crow 

 

[nervoustrig]

Thanks for the accurateshoooters link. I read all 4 pages with interest. The thread makes a pretty good argument to avoid overpolishing. Multiple people spoke of rapid copper fouling after polishing. And it didn’t contain a single first-hand or otherwise credible recommendation to polish a barrel to a mirror finish.

Meanwhile however, I don’t know how well the powderburner wisdom maps onto airguns. Copper vs lead, 30,000psi vs 3000psi, cylindricals vs diabolo, high temperature vs room temperature, no lube vs lube.

I can’t recall ever hearing a complaint of an airgun barrel leading up quickly after polishing. Quite the contrary, in fact. But just to be clear, I’m not advocating for a mirror polish...I don’t do it myself so I’m not climbing out on that limb. I’m just expressing some skepticism because the concern runs counter to what others have reported.

 

[randy_68]

my process is very similar to Michaels with the same products. I only do it if I think the barrel will benefit or if it has accuracy issues and so far I have not had any that shoot worse but several that shoot better. It does work.

 

[lennyk]

how long does the m77 moly last in a barrel ?

 

[Andy.Marshall]

I've been using Kroil for over 30 years on all kinds of projects, from restoring vintage race cars to repairing 100-year-old electrical test equipment. One thing I've learned in this process is that with Kroil, which is a penetrating oil, you always need a lot less than you thought you would. It's whole thing is that it works its way into minuscule gaps in metal and does not requite a large volume of liquid to do this. What it does require is time. As their literature states, it creeps. A few drops along the inner edges of the top of a vertical barrel will quickly and easily make its way all the way down the barrel and under everything that is not molecularly bonded to the steel. If you are feeling insecure about the process, apply a few more drops after 12 hours or so, then let it sit for 24 hours.

I use Kroil almost every day in my work and hobbies, and their smallest 8 oz can lasts me nearly a year. I keep some in a micro-oiler bottle with a needle tip. It's amazing for loosening stuck screws and nuts. There's nothing better out there for that purpose.

 

[heavy-impact]

how long does the m77 moly last in a barrel ?

It's something like 65% molybdenum disulfide in a silicone carrier. I never tested to see how long it lasts but it's a long time. Another reason not to polish to a mirror finish is that a lubricant can not stay as well.

 

[lennyk]

how long does the m77 moly last in a barrel ?

It's something like 65% molybdenum disulfide in a silicone carrier. I never tested to see how long it lasts but it's a long time. Another reason not to polish to a mirror finish is that a lubricant can not stay as well.

I guess barrel needs to be really scrubbed clean before apply moly as any leading will hamper the moly staying on the barrel surface