Cases and Enfields and lube - Oh my!

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Below is from the source you listed in your last posting.

Rifle Chamber Finish & Friction Effects on Bolt Load and Case Head Thinning.

Please NOTE the author does NOT recommend lubricating the cartridge case.

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The author of the article is an engineer. Engineers are people who boldly go where everyone else has gone before. Engineers are not by inclination risk takers, they will collect vast amounts of data and analysis to prove that all paths forward are too risky. Managers are always having to kick them out of their comfort zone before they will do something new and novel.

So even though his analysis shows that the back thrust of a lubricated case will not exceed the design limits of the action, Varmit Al will always take the ultra conservative position: "Don’t jump in the deep end of the pool! "

Still, he did say:

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CONCLUSION.... A polished or low friction chamber decreases the plastic strain near the case head and reduces the chance of case head separation on subsequent reloads.

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It is the cartridge case that is the weak link in the system, not the action.

As I am actually trying to run a No.4 action w/ standard controlled pressure loads to destruction in a limited number of rounds, the 300WSM seems a good choice if things work out. I've more 300Win Mag brass and a friend has reloading dies, though.

Don't want a failure on the first shot. A progressive degradation, accellerated by the greater forces of the more powerful cartridge, is desired. Periodic dye penetrant tests will be performed.


ETA The structural failures of AR15 bolts are actually driven by more than just rearward thrust loads. The 6.8SPC cartridge, being of larger base dia. than the 5.56, also weakens the bolt due to the larger counterbore in the bolt face. In actual fact, though, the real drama in that platform as regards bolt life, is that the torsional loads on the bolt are increased quite a bit by the gas port placement in carbines, which is the real reason to use a 6.8SPC- better terminal ballistics in a reduced size package. Bolt life grows shorter even in 5.56 as barrel length is reduced, esp. w/ DI gas systems. (Generally, the lugs closest to the "missing" lug at the extractor cut fail first. Often, the rifle will continue to function if the broken lug doesn't get caught in the "works". The other common failure point is at the cam pin hole.) Rifle length systems rarely have failures, due to a "gentler" operating cycle.

So, let's not muddy the waters further w/ different designs. Stick to "springy" rear locking types.

The last Engineering project I worked on was upgrading the water lines which fed our Military bases 1917 warehouses. Our in-house engineer would not listen to the senior construction inspector about also upgrading the sprinkler system water lines inside these warehouses. When the water pressure was turned on the fire sprinkler heads were blown off the sprinkler lines and the Engineer tried to blame the construction inspector.

At Edwards Air Force Base when the Lockheed C-5A first came out and was under testing and development the first airman to fall off the T-tail wearing a safety harness broke both of his legs. The aircraft engineer used standard average day temperature as the stretch factor for the safety rope and harness. The safety rope had to be shortened 12 feet under “real world” conditions. Less than a week later an airman fell off the fuselage wearing a safety harness and broke his arm. This time the rope wasn’t the contributing factor because both safety anchor points for the safety harness ripped loose from the aircraft. The “engineers” miscalculated the stress and load factors to the aluminum skin of the aircraft.

Varmint Al has a computer program called “LS-DYNA software” in which he inputted all the data and information. Varmint Al is not a firearms engineer nor did he attach strain gauges to an actual rifle to cross check real world data with the software simulation estimates.

With a suggested starting load for reloading the .303 British at 38,000 CUP and a greased cartridge case you would have the equivalent of 53,300 CUP on the bolt face. At a mid range load as Parashooter recommends with a greased cartridge case you would have the equivalent of 60,000 CUP on the bolt face. And at 45,000 CUP and a greased cartridge case you would have the equivalent of 63,000 CUP on the bolt face which is the same pressure equivalent of firing a proof test cartridge .

So let us all understand what the people who recommend lubing cases are telling us.

1. Disregard all safety warnings put out by the firearms industry and the military about bolt thrust and lubing cartridge cases.
2. Trust a computer program the firearms industry doesn’t even use.
3. Trust forum members we don’t even know who are not firearms engineers, and do not work for any firearms company nor do they have they the same test equipment the firearms industry uses.

SURGEON GENERAL'S WARNING: Smoking Causes Lung Cancer, Heart Disease, Emphysema.

Ok people smoke em’ if you got em’. Trust me, if you lubricate your cigarettes smoking will NEVER hurt you. :rolleyes:

That's really confusing. Engineering mistakes DO happen. So what of it?

I'm NOT recommending lubing cases. However, it does tie in with the dire warnings that a certain NRA has made concerning the shooting of 7.62x51 in an action presumably designed by error prone engineers around the .303" SAA.

Sooo, how much abuse will the action take in the real world? How much is it's life span shortened by all of these "ill advised" actions, of whatever sort? What manner of failure actually occurs?

Apparently, merely firing a few thousand rounds of 7.62x51 was not enough to cause danger to the military users over twenty years. Hence the desire to "step up" the "destructive" inputs.

ETA: I do think lubing cases will increase case life in this action signifcantly, but until which point becomes a "non-expendable" item, it doesn't really make good economic/collector sense to trade rifle "life" for brass "life", UNLESS the rifle life reduction can be PROVEN to be negligable.

Grease or oil is for some auto actions to operate easier so as to not malfunction ( all the pressure that can be directed to the bolt operation for reliability) Manual bolt operation as little pressure as can be left at bolt for reliable operation.There was a higher proof load for machine guns (25-27 tpsi) for a short period of time. Normal proof 23-25 tpsi. Where does the No4 7.62 bolt stamp of 19t sit when the original proof in 303 was 23-25 tpsi just a safety margin

"Oily bores and chambers will need to be cleaned and de-greased. The design of the Lee Enfield rifle and the tapered .303 British cartridge exacerbate the problem of bolt thrust when fed greasy cartridges. Dry, oil-free chamber and ammo is required for best accuracy otherwise your best reloads will string out vertically on the target. Bullet lube and sizing die lubricant, along with greasy fingerprints are all culprits!"

Cast Bullets in the Lee Enfield Rifle

Makes me wonder how many people actually read the warnings in the reloading manuals.

I'll put my money on the Sierra reloading manual. ;)

https://www.milsurps.com/images/impo.../sierra1-1.jpg

https://www.milsurps.com/images/impo.../sierra2-1.jpg

Smoke em' if you got em' :rolleyes:

At Gunboards after my posting how to fire form .303 cases using the rubber o-ring method, one avid reloader tested Remington cases to destruction WITHOUT LUBING these cases.

We do NOT need to lube .303 cases and subject our Enfield’s to increased bolt thrust. All that’s needed is to fire form your .303 cases using the rubber o-ring method and neck size only which extended case reloading life to over 30 reloadings. ;)
(Makes me wonder how many reloadings you can get from Prvi Partizan cases) :D

https://www.milsurps.com/images/impo...3/oring1-1.jpg

https://www.milsurps.com/images/impo...3/oring2-1.jpg

https://www.milsurps.com/images/impo...3/oring3-1.jpg

https://www.milsurps.com/images/impo...3/oring4-1.jpg

Over 30 reloadings without any case failures and WITHOUT lubing the cases and ignoring all the safety warnings about bolt thrust. :thup:

Looks like a no brainer to me........................

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Makes me wonder how many people actually read the warnings in the reloading manuals.

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I've certainly read many such warnings. I've also seen warnings from gun and ammo manufacturers asserting handloading is a dangerous practice that should be avoided. And although I don't doubt some individuals probably aren't capable of becoming safe handloaders, that doesn't mean it's always true for everyone.

How about instead of just parroting a bunch of stuff we've all seen before, you contribute to an actual advancement of knowledge by using your considerable research skills to find us some examples of Lee-Enfields documented as being damaged by firing normal ammunition with lightly-lubed cases? Or maybe you could dig up some actual test reports - not just the same old unsupported assertions - detailing the difference in thrust between lubed and dry conditions and the methodology used in the test. That would be helpful. What you've been doing is no more useful than standing on a corner yelling "I'm right and anyone who doesn't agree with me is crazy."

Maybe you are right. My limited tests and a fair amount of experience tell me it's possible other conclusions might be valid, too. Wouldn't it be a heap more interesting for all of us if you'd help investigating the question instead of just repeating the same old stuff to us over and over? I know you have the ability to make a real contribution here and don't understand why you aren't doing so.

>>>With a suggested starting load for reloading the .303 British at 38,000 CUP and a greased cartridge case you would have the equivalent of 53,300 CUP on the bolt face.<<<

Please show the basis of the calculations that makes your numbers right and everyone else wrong.
It seems Varmint Al is correct when you quote him but he is incorrect when someone else quotes him?