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1/10/2007 3:29:05 PM EDT
In my search to find the best off the shelf home defense round for my new 1/7 carbine I've ended up with two boxes of Black Hills .223 68 GR Match HP-Moly rounds. Lot's of other heavy bullet rounds for testing too. This ammo won't be for blastin just for repelling boarders if necessary

I've read so much info lately that i've managed to confuse myself more than normal. No suprise here.

All things being equal I will obviously use what groups best and is most reliable but my stoopid question is will the Moly negatively react in any way with my chrome lined barrel?

I meant to buy 68GR Black Hills Match HP ust not with Moly coating.

Thanks for the advise.
1/10/2007 4:09:34 PM EDT
[#1]
Rocketman from what I can remember Moly has the bad trait of trapping moisture. I personally stay away from it. I'm sure someone will be here shortly to give you a more detailed answer.

Here is a quote from AMMO-ORACLE?

Q. What is Moly?  What is it good for?

The term “Moly” refers to Molybdenum Disulphide.  This is an extremely fine powder which acts as an inert lubricant between the bullet and the bore.  It is coated onto bullets to reduce the friction incurred on the bullet as it passes down the bore.  The reduced friction is said to prolong barrel life, increase velocity and the ballistic coefficient, and increase accuracy.  The moly coating does not build up in the barrel, as each successive shot removes any excess material from the previous round.

If you are worried about barrel break-in on new rifles, do not use moly to begin with.  The extra friction from an uncoated bullet is necessary for proper break-in.


Q. Moly sounds hella-cool.  I'm going to use it with all my rounds from now on!

Slow down there chief, Moly isn't sliced bread or anything.

The biggest downside is that Moly is hygroscopic – meaning it is capable of absorbing water from the air.  This water is then trapped between the moly coating and the barrel, which is definitely not a good thing.  A quick fix to this problem is to run an oiled patch through the barrel after each shooting session.  The oil will block moisture from being absorbed.

Moly is also extremely messy, and it likes to stick to everything.  It is also easily rubbed off of bullets, leaving a slippery film on whatever it touches.  With practice and experience, however, this can be minimized.

The biggest threat to barrel life is not addressed by the use of moly coated bullets: Throat erosion.  Throat erosion is not caused by the friction of the bullet, rather the high pressure and high temperature gases that are present in every shot.  It is not very often that a rifle barrel wears out it’s rifling before it suffers from extensive throat erosion.
1/10/2007 4:24:25 PM EDT
[#2]
Ah. That pesky ammo oracle!

1/10/2007 6:24:08 PM EDT
[#3]
Yea I heard that. That 1/12 with the 55gr looked pretty good in the 70's. I always got a kicking out of running the butts on qual day at 500 yards and seeing all the keyhole rounds. Scored just like the pretty round holes at the 300m yrd line though.
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