Chamber shoulder and case shoulder gauge for .303?

[NuJudge]

I don't know how I missed the .303 case gauge on the Wilson website.

I looked at the RCBS website, and saw their cartridge gauge, but saw they did not offer it in .303. I believe what you are telling me is that I can get .303 shoulder movement information from using the .308 RCBS Cartridge gauge. Is this true?

I am familiar with the differences in backthrust based on chamber conditions. I recently saw a series of pictures of .30-30 cartridge case heads with pressure indicating film on them: oiled cartridges showed the most pressure, followed by cartridges with the precise headspace of the chamber, the least pressure shown by chambers .010" over cartridge headspace. When studying action springyness, I'm going to have to pay particular attention to maintaining several standard chamber conditions: not just oil, but the same headspace.

[Edward Horton]

I use the .308 precision Mic on my 7.62 Ishapore 2A1 and NOT on the .303 British, if you know how long your .308/7.62 case is you can get your headspace with feeler gauges or an unfired case and a spent primer and not need headspace gauges.



On the Enfield you can insert feeler gauges between the right locking lug and the receiver to get your headspace (head gap clearance) with a unfired case in the chamber. You can also insert a fired primer in the same empty case to get your head gap clearance by starting the primer in the primer pocket and then chambering the case. Measuring the case length before and after inserting the primer gives you head gap clearance and this added to your rim thickness gives you your actual headspace measurement.

[ireload2]

EH posted

>>>If I remember correctly cartridge cases are made from five different grades or specifications of brass and American .303 cases are one or two grades below what would be used in the upper pressure category as in the .308 Winchester and above.<<<<

Do you have any citations to back this up?

[Edward Horton]

EH posted

>>>If I remember correctly cartridge cases are made from five different grades or specifications of brass and American .303 cases are one or two grades below what would be used in the upper pressure category as in the .308 Winchester and above.<<<<

Do you have any citations to back this up?

The last time I had a citation it cost me over $100.00

Are you checking my memory or do you think a 38 Special cartridge case designed for a max chamber pressure of 17,000 Cup is made from the same grade brass as a 300 Win Mag at 54,000 CUP.

As I said “if I remember correctly” cartridge cases are made from five different grades of brass BUT the requirements can vary for individual calibers and the pressure rating of the cartridge case.

The photos below are not from what I read some time ago because cases are manufactured by two different methods, drawing and extrusion and the requirements and annealing are different for these two methods. Also the specs for military grade cartridge brass is different from commercial grade brass and I may have read it in a military manual.

As you can see below the copper and Zink mixture varies with the different hardness and pressure ratings and the variations in actual mixtures is endless depending on requirements.

As an inspector at a military depot the contractors were required to submit samples of their cartridge brass for testing and acceptance.

[ireload2]

Your listing is of the different material conditions for 70/30cartridge brass.
Depending on how the cartridge is manufactured including annealing all the material conditions from full hard to annealed may be found in the same case. Some cases may even include the extra hard and dead soft condition.
If you would like to see the military specifications they can be found at the US government "Assist" web site. Pick the quick search option and enter key word for a title such as "cartridge"
As you learn to use the site you will figure out how to get to cartridge and then within that document you will find a specification for "brass, cartridge"

[Edward Horton]

Ireload2

The commercial 30-06 cases in my Springfield 03-A3 with its larger diameter chamber and longer headspace lasted much longer than commercial .303 cases in my Enfields with there equally long and fat chamber.

This tells me the American made .303 British cases I’m using are not designed for the advertised pressures that are in our reloading manuals, on top of this you have thin rims and small base diameter of our American made cases.

You used different cases to solve your problem that fit the chamber better, and I want to find out what is wrong with the existing .303 cases and see if the manufactures will improve them.

Privi Partizan is making .303 cases with larger base diameters and thicker rims and when fired do not stretch in the base web area on the first firing in Enfield’s with headspace in excess of SAAMI standards.

I’m playing the part of the devil's advocate and not blaming the Enfield Rifle for the problems I believe the cases are causing, I’m not looking for something to blame the problem on I want to fix the problem.

I have already seen the specs for military brass because I worked as an Inspector at a military depot, what I want to see is the American commercial specs for .303 cases and what chamber pressure the commercial factory .303 ammunition is loaded to.

In the photo below on top is South African PMP .303 loaded ammunition in a Wilson’s case gauge, it has a larger base diameter and thicker rims than American made cases, in the bottom photo is a new unfired Remington case and they don’t even know where to put the shoulder of the case.

If our American manufactures don’t know where to put the shoulder of the .303 case why should I trust them to make cases out of brass rated for 45,000 CUP.

[ireload2]

My best suggestion is to get the British engineering drawings for the maximum and minimum cartridges and compare them to the maximum British chamber drawing. I think you will find a lot of clearance built in. (As long as manufacturers comply with the industry standards they are covering their butts liability wise.)

Then get the SAAMI drawings for the same and compare. you will probably find the same huge amount of clearance.

Once you have done this compare a similar cartridge and chamber that you know gives long case life. That includes almost any other cartridge except a .22 Hornet and a 6.5 Arisaka. I think you will find the Brits designed in more clearance than almost any cartridge developed after the black powder era ended.

This same issue occurs with the Japanese 6.5 Arisaka in both the Type 38 rifle and the Japanese Type I Italian Carcano rifle. The chamber is much larger than current available Norma brass. No blaming WW for this one. I have both Jap rifles and the cartridge to chamber fit is terrible. They even call the bulging cases the Norma bulge. On the other hand I have a 6.5 Italian Carcano. It has a normal chamber to case fit and the brass appears that it will last a long time.

I understand why you are putting out this effort. The .303 was the second cartridge that I ever loaded for in about 1969 or 1970. That first rifle was a worn out Lithgow 1916 #1 MKIII* with a new 1942 barrel. I had separations with it right from the start with Federal, Winchester, Remington and Norma brass. I did have some boxer primed military brass WRA 1943 that lasted a little better. I sold that rifle to my brother and bought a #4MkI. It did the same thing with the same dies and brass. I sold that rifle and now have another #4Mk1. This rifle has not been so bad but I started out with very light loads in it. Due to my past experience I never shot the rifle much since I am not in the habit of wasting money on new brass that will promptly separate.

About 15 years ago I found some 30-40 Krag brass by both Remington and Winchester that checked .455 at the rim. I made a few cases and they lasted much better than any .303 brass. At that point I thought I would try the .444 marlin brass not because it was cost effective but just to learn if they cut down the incidence of failure. They did though I have not shot them all that much either. They are a lot of work but I did the work to learn more about making brass last.

In our discussion about the case grabbing the chamber wall, there is one contradiction with the Lee-Enfield. If you try to insure the case sticks to the chamber the pressure of the load is high enough to stretch the case ruining it. And if you lube the case it puts more load on the action. The problem is neither is a nice option. The 500 new WW cases that you bought cost more than my rifle is worth. I would never use and destroy that many nice new cases just to lighten the load on the action. For me my rifle is more expendable than 500 new cases. That is why I tend to fire form with lubed cases and use reduced loads.

Another thing you might look at is the weight of the various cases.
Winchester brass is known to be light and relatively hard. In a close fit chamber that works well for lots of powder capacity and high pressure.
However the hard brass is less ductile and is easier to crack.
The HXP brass that I have weighs about 30 grains more than WW brass so it has heavier side walls. The .444 brass also weighs about the same as the HXP brass 190 grains. The 444 brass has much heavier side walls near the head than the brands of .303 brass that I have sectioned. I will restate though that I have use both Remington & WW .303 brass in 6.5 Dutch rifles with zero head separations. However the 6.5 Dutch chambers are a very close fit for the brass and the Mannlicher action is pretty strong and lock in the front.

I am surprised that the commercial brass companies sell brass as light and as thin as they do for .303s. They separate a lot creating a hazard. If it were me I would make the case walls much thicker to stop the separating or get out of the business. While thicker case would cost a little more I am sure consumers would pay a $.10 for better brass.I don't think there is anything wrong with their brass in a more normal applications but Lee-Enfields are not normal.

I have always found the Wilson tools very high quality but in the case of the .303 the actual head space is determined by the rim thickness. You could talk to the people at Wilson to find out if the shoulder in the gauge is supposed to mean anything. You might try giving Mike at CH Tool & Die
a call and asking him about the drawings even if you have to bribe him buy buying a set of dies. He sent me Zerox copies of some original British ammo drawing for the 7.65 Argentine Mauser. Even with engineering drawing you have to be careful because some sources differ.

While you are comparing new cases to you Wilson gauge have you tried fired cases in it? The once fired HXP brass that I bought has some of the goofiest shoulders that i have ever seen. I think there may be a lot of difference between loaded ammo and Lee-Enfield chambers.

In the end you may find that .303 British brass can be a lot better but I don't know how you get a company to change their product. They have been that way longer than I have been loading. My approach was to try something on my own and not worry about changing the big companies.

When do you get to go back to the other forum?

[Edward Horton]

Ireload

You are not telling me anything I do not already know because I have been reloading for over 40 years and we have gone over all this before. The best method I have found for fire forming .303 cases is using the rubber o-ring method and you will have zero case stretching because you have zero head gap clearance.

In the posting at Gunboards that was deleted I went into detail on this method, in Parashooters Headspace 101 he used nylon monofilament instead of the rubber o-ring to hold the case against the bolt face and reloaded the cases 19 times without any case stretching.

The secret is in the fire forming and not letting the case stretching in the web area get started in the first place.

I also said before the American manufactures are loading factory ammunition to below 43,000 CUP and are using a lower pressure rated cartridge brass which makes them fall apart above that pressure.

[ireload2]

You may have a lot of reloading experience but so do I. Plus my entire working career had been involved in machining, metal working and engineering.
You assert good things about your method but have you actually shot any brass to destruction?
What size O ring are you using so I can duplicate your tests?
I would like to try the O rings with .444 brass and .405 brass.

One of the reasons that you may have found no thinning in the HXP brass you have I believe you said it had been fired in a machine gun. That might make a big difference if the machine guns is much heavier and stronger than a Lee-Enfield action.
Is the machine gun fired HXP still available anywhere.

Have you checked your fired brass in the Wilson gauge?
It seems you conveniently ignore my questions.

[Edward Horton]

You are forgetting something very important here, I did not ask you for any advice nor do I want any of your advice, the main reason you came here is to extend the argument, fight, disagreement we had at Gunboards to this forum.

This thread last saw activity before you asked your question on April 6, 2009 and that was over a month ago, the only reason you are here is to stir up more trouble like you did at Gunboards. Take your grudge, ego and B.S. and go someplace else.

Have a nice day