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View Full Version : gunpowder containing graphite lubricant...?



skyugo
01-06-08, 12:34
i was reading somewhere, probably here, that powder for m16's should contain some kind of graphite dust, so that when it's fired it will essentially dry lube your bolt.

is this a myth?

what powders will do this?

TOrrock
01-06-08, 16:07
Myth.

The big reason the early M16's were having issues was the switch from IMR powder to WWII style ball powder.

5pins
01-06-08, 16:17
Graphite is added to powder to aid in the in the ammunition manufacturing process. It lubricates the powder so it will run through the machinery better. It will not dry lube the bolt.

Bill Alexander
01-06-08, 19:08
Graphite is added to the manufacturing process to prevent static build up. Correctly formulated propellents which have been manufactured for use in a semi automatic rifle will be more heavily graphited to provide some level of lubrication in the gas residue. Most new military powders will have the graphite level specified within the overall performance specifications. Graphite is graphite unless you reach the sublimation temperature, 2400 C it will deposit into whatever mechanism it is blown onto and it will provide a level of dry lubrication.

Graphite in powder is a very careful balancing act. The burn characteristics of the powder and the other chemicals used to retard the burn rate and remove the residual water from manufacturing must produce a very fine soft residue rather than heavy baked contamination. The newer generation of propellents are well engineered in this respect. The graphite rarely takes the form of dust within the powder but rather is diffused into the surface of the powder grains.

One of the things we are seeing is that the powders are actually becoming more and more specialized. If you shift case volume or operating pressures everything changes and what was a perfect powder can become a disaster.

I will try and persuade a few of the powder design people I work with to drop in at this site. There seams to be an interest in this area and they are the experts.

Bill Alexander

5pins
01-06-08, 20:29
I will try and persuade a few of the powder design people I work with to drop in at this site. There seams to be an interest in this area and they are the experts.


That would be cool!

skyugo
01-06-08, 22:02
Myth.

The big reason the early M16's were having issues was the switch from IMR powder to WWII style ball powder.

i've actually been doing my loads with IMR.

seems very clean.
maybe i'll stick with that. a lot of people complain about it metering, but it seems to work ok in my lee measure..

TY44934
01-06-08, 23:04
Can't say as to rifle propellant.

Pistol powders CAN have a lot added; worst examples I can think of are filthy Red Dot and HP-38/Win 231 - both leave a lot of graphite soot behind too. To their credit, they now have a much cleaner burning version of Red Dot called "E3" which appears to have a much lower level of graphite additive, though it is still a double based powder and therefore less desireable for competition use (USPSA & IDPA) where the handgun must remain clean enough over 150 rounds to function perfectly without cleaning.

Currently for competition, I like single base powders, including Solo 1000, all Vihta Vouri powders and 4756.