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Old September 10, 2012, 10:53 AM   #20
Slamfire
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Join Date: May 27, 2007
Posts: 3,873
Millions of moly lubed bullets have been fired in rifle matches and never a pressure problem reported. I have dipped hundreds of 303 Bullets in axle grease to reduce bullet fouling, and reduce fouling it did and my Enfield is doing just fine. as stated earlier, British shooters were greasing their bullets for decades, as they were buying the same sort of "never nickle" grease that Americans had used before the Military banned the practice.

Hopefully the greased bullet discussion will be nearing an end, but Hatcher’ Notebook and Townsend Whelen are the ground zero of the concept that lubricated cases are dangerous.

Townsend Whelen was in charge of the manufacture of the tin can ammunition, and as a man who would not publically admit to making a huge mistake, he spent the rest of his life scapegoating grease and oil on cartridges. Gunwriters, who are at best are Journalism majors, take this at face value, amplify, extend it, created a fantasy world around the concept. I like Dick Culver, but here, he has created a morality play about the evil, stupid people who greased their bullets. http://www.odcmp.org/1101/can.pdf This scape goating has been going on in the American press since Townsend Whelen retired and Hatcher put out his Notebook.

As for the 50% increased thrust number, love to see a technical report on that. I do know the American Rifleman had an article on the British Lubed cartridge proof system, perhaps an amplification of that?

Hatcher never blamed lubricated cartridges in service rifles, it was all about greased bullets.

Read the front of Hatcher’s Notebook about his experiences testing early semi automatic service rifles. He personally shot or oversaw service rifles that had oiling pads or used microcrystalline wax as a cartridge lubricant. The most well known was the Pedersen rifle.

There were several factors that doomed the Pedersen rifle, the major one was the cartridge, it was not a 30-06, and the microwax.

I am unaware of any other service rifles that used lubricated service rifle cartridges before the advent of steel cased ammunition. And as I have said earlier, fluted chambers removed the need for case lubrication in blowback actions.

However, the US experiemented in the 50’s with Teflon coatings in 30-06 and 45 ACP ammunition. In the Sept 1973 American Rifleman Dope bag pg 84, there is a picture of a Teflon coated FA54 30-06 ball round. The Army had used steel case ammunition in WW2, that had a zinc chromate coating which caused extraction difficulties. So in the 50’s they are coating steel cases with wax, Teflon, other materials to reduce the friction between case and chamber. From what I heard, the cost of the coatings was more than the savings, and the US military decided to keep using brass cases.

Small arms development was a minor issue, dollar wise, in the 50’s. From what I have seen in terms of reports, the major money was being spent on 20mm cannon development. The good old 50 caliber browning could not put enough lead on target to ensure destruction of jets. You will see report titles, such as the one I posted, experiments to lower the cost of 20mm brass cases and get the cyclic rate up.

This is a report from the period, the title is on DTIC but not the test. Would make interesting reading if I could find it.:

TEST OF TEFLON AND MICROCRYSTALLINE WAX CASE-CHAMBER LUBRICANT APPLIED TO BRASS-CASED 20MM AMMUNITION , DIEWERT,JACK R , ABERDEEN PROVING GROUND MD ,Report Date: 01-Dec-1954

As for analytic evaluations of case lubrication, go to Varmit Al. Look at his analysis. http://www.varmintal.com/a243z.htm Notice at the end of it, what is worse, increased bolt thrust due to lubrication, or stretching of the case head because the chamber is dry?

Let me also recommend a visit to Mr. James Boatright’s site “The Well guided bullet”
http://www.thewellguidedbullet.com/m...al_studies.htm

A bunch of interesting articles under mechanical studies, one of which is:

Yielding of Brass Case Walls in the Chamber A Technical Note 30 June 2009 James A. Boatright

As a footnote:

There are two ways which lubricated cases could cause problems. The first are bottlenecked cases with too much headspace. A case with excessive headspace is going to peen the bolt face, lubricating the case will increase action peening. The second is for people who load over pressure cartridges. There is a tiny amount of load reduction on the bolt face with dry cases, remove that, and the load will be 100% on the bolt face. But the real answer to that is not to load over pressure ammunition.

And one more. You need case friction with blackpowder cartridges. BPCR competitors stick a tube in the barrel and blow, to keep the fouling moist. Blackpowder shooters have reported that with slick cases (due to breath moisture) the cartridge case is pulled up the barrel! Maybe their crimps are so strong that the crimp stretches the case up to the throat.
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