All this headspace information

[Bindi2]

Patrick i would change [2] use a neck sizing die only correctly adjusted.
The rest is as Son said to Ed we are on the same hymn sheet though i have some reservation about [1] centralizing cases to chamber maybe the option

[Patrick Chadwick]

Correctly adjusted, of course. The essential message is: adjust the ammo to fit the rifle, not the other way around.

Some of those who get steamed up about "headspace issues" should get out a bit more and fire the old black powder cartridge rifles.

OK, so there is even a CIP data sheet for 8.15x60R. So what have I got? I suppose you could say an 8.14x59.5R and a 8.16x60.5R or whatever. You just have to accept that each one requires individually fire-formed cases. And the discrepancy between the 1905 Carl Gustaf and the Schultz & Larsen M69 points out that the same applies to more modern calibers, although not so obviously.

Patrick

[Patrick Chadwick]

This link shows how pointless it is to use SAAMI gauges on a rifle that was not built to SAAMI standards. In this case, the 6.5x55 (M96 / Carl Gustav / Swedish Mauser)

http://dutchman.rebooty.com/headspace.html

Patrick

[Edward Horton]

Patrick Chadwick


It took a while for the light bulb to come on but the majority of people who “jumped” on Americans about “headspace phobia” were using Greek HXP cases. As soon as I got my first Enfield I ordered a box of 500 Winchester cases that were made on a Friday before a holiday (translation- This batch of Winchester cases was never made to shoot in a Enfield chamber and maybe not even a SAAMI chamber)

Here in the U.S. military match grade cases made at the Lake City arsenal were considered the very best for reloading the 30-06 and .308/7.62 “IF” you could find them. On my favorite shooter I removed the non-spec tightly headspaced bolthead and installed the original bolt head that headspaces at .067 and now fire form my cases using the rubber o-ring method using Remington cases.

It is NOT pointless for anyone who reloads to tighten up your headspace to SAAMI standards, when you shoot cases designed to civilian SAAMI standards. Please remember between .064 and .067 “BOTH” SAAMI and British headspace standards are being met. The less head gap clearance or “air space” between the rear of the case and the bolt face the less the case can stretch and become “deformed” i.e. warped, bent or banana shaped and then misaligned with the bore.

I do not belong to the “.074 is good enough for me club” and even the Canadian military tightened up the headspace settings for their No.4 Enfield’s. I also believe the Canadian headspace standards were changed for a very good reason on the Enfield Rifle, and this is because they are shooting the cartridges made today and not the cartridges of yesteryear.

In the book below written in 2005 by Ian Skennerton and Brian Labudda it tells you to set your headspace .003 (three thousandths) larger than your rim thickness. With the American made cases I’m using this means setting my headspace at .061 or .003 under minimum headspace.



Headspace example: on a SAAMI .308 chamber and a case .002 shorter than minimum headspace with the rifle headspace set at 1.633 you would have .005 head gap clearance. On a .303 Enfield with the headspace set at .073 and a rim thickness of .058 you would have .015 head gap clearance. Which case is going to stretch the most in the web area when fired?

Below is a photo of a fired Prvi Partizan case on the left and a fired Greek HXP case on the right, the Prvi Partizan case is much thicker and larger in diameter in the base web area than the much vaunted Greek HXP cases. Guess which cases I have been buying “when I can find them”.



I do NOT oil or grease any cartridge before shooting them and my chambers and bore are cleaned, dry and free of any oils or grease before shooting. Cartridge cases were designed to grip the chamber walls and I see no reason in preventing this.

Please note many people do oil their cases and some of them are here and alive to tell us about it, I chose not to and I also don’t swim when sharks, piranhas or alligators are in the water.

With all humor aside many people do safely oil their cases to fire form them and it can be done safely “at the correct reduced loadings and lower pressure levels” when reloading and fire forming your cases.

On the flip side of this I would NEVER think of shooting factory loaded ammunition or reloaded ammunition at higher pressure levels in a chamber with oil or grease in it due to the increased bolt thrust.

[Parashooter]

. . . the die must be set up (as also noted in recent postings ) to allow for the spring-back in the press, otherwise the result can be a case with the neck too far forwards that has to be cammed into the chamber, and can be very stiff to extract.
. . .
Or take a look at the bolt on the Swiss G96, 96/11 or K11, with lugs at the back. Then try and find "head separation" on the forums that cover Swiss rifles. No luck.
. . .
1) First fire-forming with a slightly greasy case to get the maximum forming effect. I.e. merely wipe lube off case after sizing, but do not degrease it.
2) For all subsequent reloads, use neck-sizing with a properly adjusted press.
3) Except for that first fire-forming, keep all loaded cases dry to avoid continual and unecessary stress on the bolt lugs.
4) Forget SAAMI gauges, except for US-made rifles and ammo.
. . .
Patrick

Patrick, it seems you've come a long way toward appreciating some parts of the issue but still have areas of misunderstanding.

Press "spring-back" is negligible in neck sizing, simply because sizing just the neck takes very little force. Press flex is an issue when full-length sizing, especially with thick, heavy cases. The primary source of neck-sizing problems is attempting to do it with FL dies that contact the body before the neck is sized far enough. This contact often compresses the body and displaces the shoulder forward.


Smoked cases reveal body contact when attempting to neck-size with full-length sizer dies.

Head separations certainly occur with the Swiss 7.5 rifles and have been discussed at length on the forums dedicated to these arms. Here's an image from one such thread -



While fire-forming with lubed cases is an effective technique for some handloaders, others object to the practice on the grounds that it delivers unnecessary stress to the bolt and receiver. Fire-forming with some kind of spacer ahead of the rim is nearly as effective in reducing initial stretch and avoids the controversy. A spacer that also serves to center the case is additionally useful, especially with fat chambers or skinny brass.

Effective neck sizing often requires special dies, dimensioned to clear body and shoulder. It is the die position that is adjusted to give the amount of sizing desired, not the press. Most common reloading presses aren't readily adjustable in any way that affects neck sizing.

Whether or not increased stress on the rifle resulting from regular use of lubed cases is more important than reduced stress on the cases is arguable and will vary with the relative value and strength of the rifle and of the cases.

It seems pointless for a recreational handloader to obsess about gauges or varied specifications when the truly critical factor, the actual fit of his handloaded ammo in his individual rifle(s), can be determined and managed using no other gauge than the rifle itself and his "calibrated" fingers. Leave headspace gauges to gunsmiths fitting barrels or bolts, armorers or buyers checking numerous used rifles, or commercial reloaders producing ammo to be used in a variety of arms - and life gets much simpler.

[villiers]

"Fire-forming with some kind of spacer ahead of the rim is nearly as effective in reducing initial stretch and avoids the controversy. A spacer that also serves to center the case is additionally useful, especially with fat chambers or skinny brass."

I´d be grateful for further information (if possible with pics) of these spacers.

[Edward Horton]

I read about using rubber o-rings in the old Jouster forum, I think Terry in Victoria brought it up. Below I fire formed 50 rounds using the o-ring method with the extractor removed. As the o-ring is compressed it centers the rear of the case in the chamber promoting equal case expansion. The cases can be removed with a flick of your finger nail or a small common screw driver.





Headspace or head gap clearance determines o-ring size.





Cases fire formed with the rubber o-ring had absolutely no thinning or stretching in the web area, my gauge tells no lies.

[Bindi2]

Parashooters post shows why i use LEE neck sizing collet dies.
Ed have you tried the o rings with WW brass. The only way i will get enough wider headspace is to face a bolt head off. My 0 is as near to perfect as you can get or as good as a new bought one. Head separation still occurs

[Edward Horton]

Bindi2

The box of 500 empty Winchester cases I bought after I got my first Enfield drove me to the point of excessive compulsive headspace phobia. I personally would not recommend Winchester cases for reloading the .303 British Enfield, and I have been reloading for over 40 years. There is a chance the Winchester .303 cases I purchased are defective, BUT prior to this I NEVER had any problem with Winchester cases in any commercial rifle with a SAAMI chamber.

I’m using Remington cases right now and I have 60 rounds of factory Prvi Partizan to shoot and reload. The Prvi cases are the thickest by .010 than any other manufacture and have a larger base diameter and thicker rims than any American made case.

Beelzebub the New Zealander at the Gunboards told me 5 years ago that the Priv Partizan cases were the best he ever reloaded.

Below a factory loaded Prvi .303 case fired without any o-ring, the headspace was .067 and the cases did not thin or stretch in the web area of the case. (these Prvi cases may be made with Kryptonite)



Use your Winchester cases for fishing weights and switch to a better brand of brass that fits these silly Enfield inch non-SAAMI military chambers.

If you use American made cases keep your pressures below 43,000 CUP.

[Bindi2]

The problem is when the supply was only, you take what is available but i have now seen a brand name change big time. Poor proforming projectiles, leftovers have been made into sinkers on many occassions, havent had much success making lures out of cases and the mighty Barra is to far away for a quick fishing trip. Interesting reading the Varget data exactly the same as my ADI book but with the pressures added. Some other numbers are the same in some loads but vary in others, wonder whose data is right for the same powder but then different place different time different conditions