As I was browsing all the usual suspects for ordering Sierra Matchking's on-line and I saw a lot of the .308 offerings in Moly.  Does the little bit of extra BC make much of a difference.  Anyone seeing any slight gain in accuracy?

There's no BC change.  You see slightly lower pressures which allow you, if you care to, bump the charge a bit and get them slightly faster (but not enough to see in how you operate your sight knobs).  Saw no delta in accuracy.



Extra hassle/expense for virtually zero tangible benefit.

Moly was all the rage five or six years ago.  Hardly ever seen now. Had several friends try it.  No one noticed any great improvement.  If you shot like  Tubb it might be worthwhile.  I know I'll never be a tenth of the shooter he is, so its plain naked bullets for me.

The only proven advantages are a small velocity gain and reduced fouling, which allows longer intervals before cleaning.  The latter is important to competitors facing long strings of fire with no time for cleaning.  I shoot NRA Highpower and a full match is 88 shots (plus any alibi strings), with the biggest demand for accuracy in the last stage at 600 yards.  Varmint hunters and 3-gun shooters also benefit from this.  The extra bit of velocity can also be important, such as when shooting the .223 at 1000 yards in NRA Long Range/Palma competition; even with the best available bullets it's difficult to keep them supersonic to 1000.  The use of moly isn't mainstream, but there are niches where a lot of folks swear by it.  I particularly like the ease of cleaning: 2 patches wet with Kroil, 2 dry patches and that's it!

I like moly for my Hyper Velocity .22s (.220 Swift, .22-250, .22-6mm AI) for reduced throat erosion, but I do not use it for any others guns because I hate the Kroil/JB Bore Paste cleaning regimen.

I use it.  I get lower SDs.  Cleaning is not an issue, I use Pro Shot Copper Solvent IV and it gets ALL of the crud out.  No need for Kroil and JB.

Cleaning the barrel is a lot of work, due to moly build up. It makes the barrel last longer, better accuracy and better chrony numbers, but the groups size are about the same. To much time cleaning for a small gain. That's IMHO.

Mike  

Moly only builds up to a point then stops. I've gone through 7 or 8 barrels, and I find I get a little more life out of them with moly, maybe because I don't use a brush and don't clean out the moly. I just do the two patches with Hoppe's BR, then dry patch it, then leave regular Hoppe's in the barrel.
Why clean it out?
I've been using moly for about 12 years now, and I find the EASE of cleaning is worth it, get the same accuracy as nekid bullets.
'Borg

I tried it about 10 years ago.   Bought the powder and coated my own.   It is easy and cheap - worth a try if you want to see how it works for you.  

I was able to get more velocity, low SD's and no increase/decrease on accuracy.   For me, the cleanup and switching between coated and non-coated bullets was too much hassle... and it does introduce another variable to my reloading process.    The hygroscopic issue is a concern for me, too.  

If I shot competition (lots of shooting with just one or two calibers), I would probably use it all the time.

What (if anything) is required to swap between moly and non moly bullets? I ask because I've got a single box of 168gr Moly Hornadys I need to get rid of.

You only need to shoot them.  The first few shots can be wild until the residual moly in the bore stabilizes.



Now if you shoot plain bullets, those too can be wild until the residual moly dissipates.



How many shots?  3-5, usually.  Is it much of a change?  Only if you rifle shoots tiny knot-holes.



 

Sir, FWIW I do shoot competition and I do use it all the time.  I started using it in the late '90s and have continued to do so largely because my barrels have been conditioned with it and I have a large supply of ammo loaded with moly coated bullets.  I've read of the hydroscopic issues but never realized any problem perhaps due to the frequency and methods that I use to clean the rifles.  Especially at 600yd moly allows me to achieve slightly higher velocities within reasonable prressure limits with smaller SDs and ESs.  For me that's a plus because I get a higher terminal velocity which translates into less wind drift due to changing conditions.  Most of the time the wind seems to change a bit after I get off the scope and onto the gun and having a higher terminal velocity enables me to stay ahead of the wind.  JMHO, 7zero1.

Is that Pro Shot Copper Solvent similar to Sweets 7.62, Keith?