SMLE Headspace Problems

[7th1st]

I picked up a good 1916 SMLE, only thing that doesn't match is the rear sight. Great barrel. I figured I better headspace it before I shoot it so I bought a 30-40 Krag no-go gauge from Brownells (they said this gauge also works for .303 Brit.). I removed the extractor from the bolt head, placed the gauge in the barrel, and the bolt closed on the gauge. Did I do this right? Any suggestions? I hear some bolt heads have different headspaces.

Also, I can't get the extractor spring back in the bolt head. Any tips on this? I already broke my punch trying. I hear there is a tool that will do this. Where can I find one? Will this do it: http://www.gunpartscorp.com/catalog/Search.aspx?catid=0&filter=281780

Thanks in advance for your help.

[JBinIll]

Here's a picture of the issue type extractor spring tool http://www.arrowmark.com.au/extractorspringtools.aspx It's expensive and the company is in Australia.

The problem many times on checking headspace on these using current manufacture commercial SAMMI spec guages is that the chamber specs are different than the military ones often leading to a failed headspace reading.The link listed above has the mil-spec guages,expensive,and I have seen these guages mentioned on the Enfield Boards http://www.okiegauges.com

The tool pictured in the GunParts link is for unscrewing the fireing pin after the bolt head is removed.

[John Sukey]

To get the extractor back in, Make a double loop of dental floss and pull the extractor back in. (a single loop will break) Not a theory as I have done that.

As JB has stated, SAMMI gages will give a false reading. Military spec for a no-go is .074

By the way, ANY resistance is sufficient. You CAN force the bolt closed on a no-go gage if you try hard enough:eek:
Personaly I think this headspace thing is overblown. When the rifle was surplussed out it still had to pass proof before being sold on the civillian market. If the bolt serial matches that of the rifle, I wouldn't worry all that much about it.

[chuckindenver]

remember, the cocking assembly should be removed on any cock on closed bolt action rifle when checking headspace..
with the cocking assembly attached, its too easy to push through the gage...
cock on open rifles it really doesnt matter, i remove it out of safety....hate to have a firing pin hit a hardened gage....ouch.

[Lngstrt]

What about 7th1st's comment about the 30-40 Krag gauges subbing for .303??

[carym2a]

I would get a set of .303 gauges first, but like John S. said you can force them so be careful, then if it is out of spec then look in to getting the right size bolt head.

[JBinIll]

At the very least get a Field gauge to check it with before messing with the bolt head.Military spec if at all possible.Changing out a bolt head on the No.1MkIII is a little more complicated than just screwing one out and another in to get headspace correct.

Firing a round or two and inspecting the brass will give a good indication of the headspace if done safely by remote firing if you really suspect a problem.

[7th1st]

Thanks all. I ordered the bolt disassembly tool. Once that comes in, I'll check on a field gauge...what brand field gauge do you recommend? How is Forster?

[John Sukey]

You should have ordered two bolt disassembly tools because you will probably break one;)

[7th1st]

You should have ordered two bolt disassembly tools because you will probably break one;)

Way ahead of you John, I ordered two for that reason! ha!

[JBinIll]

Thanks all. I ordered the bolt disassembly tool. Once that comes in, I'll check on a field gauge...what brand field gauge do you recommend? How is Forster?

You indicated in your OP that you had bought a no-go gauge.Keep in mind that there are differences in each manufacturers gauge and it is recommended you stick with the same make gauges.I prefer Clymers but that's just a personal choice.I'm considering the mil-spec set that Arrow Mark offers but it's pretty expensive at $155 Aus. plus shipping to USA.

[John Sukey]

Using the disassembly tool, Don't gorilla it, try wiggling in both directions just a bit at a time. As for the Clymer gage, it can fail an otherwise serviceable rifle.

If you promise to return them, I can lend you my Canadian military headspace gages.

[JBinIll]

Using the disassembly tool, Don't gorilla it, try wiggling in both directions just a bit at a time. As for the Clymer gage, it can fail an otherwise serviceable rifle.

If you promise to return them, I can lend you my Canadian military headspace gages.

As many surplus rifles have been sold in the US in large quantities wonder why some of the companies don't offer milspec gauges even if only in limited runs.The 6.5 Swedish is another one that is hard to find gauges that are correct for the military spec and will fail using commercial gauges.

[Parashooter]

Several generations of American shooters have been convinced by bad information that something mysterious and scary called "headspace" should be checked and re-checked on almost any surplus rifle, especially Lee-Enfields. The truth is less interesting but still worth knowing.

Stripped to its essentials, with a rimmed cartridge like the .303, headspace is simply the distance between the front of the bolt and the back of the barrel. It's the space where the "head" (rim) of the cartridge fits when the rifle is loaded. Since there has to be some room to allow for varying rim thickness, the headspace is normally a bit more than necessary - giving a little extra space so the bolt can close easily, even on the thickest rim allowed.

In addition, Lee-Enfields and their ammo were often made with a fair amount of space for dirt, mud, snow and other battlefield debris between the chamber and the cartridge's body and shoulder. Since the cartridge is controlled by its rim, this clearance doesn't do any harm (except to handloaders who insist on excessive sizing).

When a full-power .303 cartridge is fired, a whole string of events occurs.
1. The firing pin shoves the case forward, rim against the breech.
2. The primer detonates. If it's not heavily crimped in place, it backs out, shoving the bolt and barrel as far apart as it can.
3. The thin, forward part of the case expands to fill and grip the chamber while the bullet moves out of the case and down the barrel.
4. The solid case head can't expand and grip the chamber, so it moves rearward, re-seating the primer, stretching the case walls just forward of the head, and stopping when it hits the bolt face. (In rear-locking actions like the Lee, the bolt and receiver also compress/stretch to add a little more movement. The higher the pressure, the more they move.)
5. If (and only if) the amount of head movement exceeds the elastic limits of the case, the cartridge separates into two pieces.

http://telecom.hartford.edu/images/headspacenaramore.gif

New cartridge cases can normally stretch a lot before breaking. Even with a minimum rim .054" thick and maximum "field" headspace of .074", the resultant .020" head clearance is well within the limits of new brass and it's very unlikely a new case will separate even if the headspace is somewhat more than the field maximum (which is pretty rare).

OK, but if one does separate I'm in deep trouble, right? Not really. It seems the short "cup" left behind the break is pretty good at keeping most of the gas where it belongs.

As a demonstration, here's a case that had been reloaded with heavy loads enough times so it was stretched near breaking. I loaded it with a 180-grain bullet and 40 grains of 4895 - a reasonably stiff charge about 2 grains under "maximum" - and fired it in a much-abused No.4 with a clean sheet of typing paper wrapped around the receiver. When I opened the bolt, the separated head extracted. The paper showed where some gas escaped. No rips or holes, just a little soot - and only where the bolt meets the barrel. Had I been shooting from the shoulder and wearing glasses, I probably wouldn't have noticed the leak at all.

http://i42.tinypic.com/11ayg6q.jpg

The point of all this is that excess headspace, even a bit beyond normal limits, isn't the terrible danger we've heard so much about. It's not a good thing for consistent ignition or long case life (although handloaders who neck-size or adjust F.L. dies carefully can control this) - but it's not a disaster waiting to happen.

Unless you're consistently getting broken cases when firing new ammo or brass, there's little reason to be worried about headspace in a Lee-Enfield that's in overall sound condition.

Handloading -

If you handload for a .303 with generous headspace, there's little need to mess with bolt heads - changing the rifle's clearances to yield longer case life. You can control cartridge end-play simply by changing technique.

When you fire a new case for the first time, use an improvised spacer ahead of the rim - anything from a precision metal washer to dental floss can work to hold the the cartridge head firmly against the bolt face and eliminate or reduce stretch even if end-play is significant. Another way of accomplishing the same end is to use a bullet seated out far enough to jam into the lands, "headspacing" on the bullet instead of the case. Such techniques are useful only if the rifle has excess headspace. With normal headspace, initial stretch isn't enough to worry about.

After you've fire-formed your new cases they will fill the chamber fully, stopping on the shoulder just like a rimless cartridge. If you neck size, you'll have zero "headspace". If you must full length size, adjust the die so the cases chamber with just a bit of resistance in the last few degrees of bolt rotation. Keep the pressures below the limit and you reduce the small amount the bolt and receiver compress/stretch on firing in a rear-locking action.

With these techniques we can make our .303 cases last for dozens of loading cycles, even if "gauge headspace" is a bit beyond .074".

US commercial gauges for .30-40 and .303 British are generally interchangeable. Here's Forster's size chart, showing that the thicknesses of the two are identical -

http://telecom.hartford.edu/images/303gaugepage2.gif

The problem for Lee Enfield fans is that the British military maximum allowable headspace was .074" - which is .004" greater than the US commercial "field" gauge thickness. Consequently, many rifles that were perfectly acceptable for British service will swallow a .070" US field gauge, causing lots of unnecessary worry.

FWIW, when using a headspace gauge made with a firing-pin-clearance hole, there's no need to remove the striker assembly when gauging a L-E. Just hold back the trigger while easing the bolt closed on the gauge. This takes the mainspring out of the process almost as effectively as removing it.

[jmoore]

Only one tiny quibble w/ Parashooter's post:

"5. If (and only if) the amount of head movement exceeds the elastic limits of the case, the cartridge separates into two pieces."

Replace "elastic" with "plastic" or equivalent. The elastic limit is that stress up to which a material will return to it's previous dimensions when the load is removed. Beyond that stress limit there will be some permanent deformation.

Rupture may occur after one severe excursion past the yield strength, or several loadings at lower levels of stress. Note that as the brass thins, the stress will increase for each following cycle as there's a reduction in area at the localized "failure zone".

I'm sure it was just a mistype!

[John Sukey]

Just a small add. When British rifles were sold out of service thay had to pass proof again before a civillian could buy them. Add to that, at the time the rifle was surplussed it was still in use by the army.

Where we encounter problems is later when bolts may have been swapped or rifles assembled from bits by some importers.

One might also note that the British army was NOT into reloading so case life did not enter into anything.

[7th1st]

Using the disassembly tool, Don't gorilla it, try wiggling in both directions just a bit at a time. As for the Clymer gage, it can fail an otherwise serviceable rifle.

If you promise to return them, I can lend you my Canadian military headspace gages.

That's very nice of you John, but I'll buy either a Forester or a Yankee Engineering gauge. It's not a bad thing to spend money to build up gauges that I very well need later on as well. Thanks for the offer!

[Edward Horton]

Firing pin disassembly:

On some firing pins the armourers crimped or swedged the last 2 or 3 threads of the firing pin to tighten the firing pin in the cocking piece.

Therefore it is always better to "tighten" the firing pin and extend the threads past the end of the cocking piece, and then try removing the firing pin by going counter clockwise and then clockwise. ("wiggling in both directions") This will help from breaking the teeth off the bolt tool, also if you clamp the cocking piece in a padded vice while pushing down hard on your bolt tool you will reduce the chances of breaking the bolt tool.

Below, from the Canadian No.4 manual.

http://i122.photobucket.com/albums/o254/bigedp51/tightencockingpiece.gif

Headspace is determined by the type cases you shoot and not the rifle.

Below a Winchester factory loaded case fired once in an Enfield with the headspace set at .067.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP4521-1.jpg

The above Winchester case stretched .009 thousandths on its first firing thus weakening the case by stretching in the base web area.

Below, base diameter and case thickness play a big part in case life when reloading. On the left is a once fired Prvi Partizan case, it is .010 thicker than any brand of case and the base diameter is larger helping to prevent case stretching. On the right is a Greek HXP case and from the expansion you can see the base diameter was smaller than the Prvi Partizan case.

NOTE: Neither the Prvi Partizan or the Greek HXP case stretched or thinned in the base web area when fired.

Headspace is determined by the type cases you shoot and not the rifle, American commercial SAAMI cases were not designed by the British military and are loaded to lower pressures than British military standards.

http://i122.photobucket.com/albums/o254/bigedp51/privihxp.jpg

By placing a rubber o-ring around the base of the case and fire forming them the word "headspace" becomes meaningless.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP5096.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6290.jpg

The rubber o-ring holds the case against the bolt face eliminating head gap clearance or excess headspace when fired and also centers the case in the chamber when the o-ring is compressed.

Firing an American made .303 case without an o-ring in the Enfield chamber can cause the case to become "banana" shaped and when fired and the case becomes warped and off center with the bore.

http://i122.photobucket.com/albums/o254/bigedp51/bent.jpg

[Parashooter]

"Headspace is determined by the type cases you shoot and not the rifle."

This is a very popular misconception. Strictly speaking, "headspace" is a rifle dimension. With a rimmed design, it is simply the distance from the rear of the barrel breech to the face of the bolt. That dimension exists whether or not there is a cartridge in the chamber. As the term implies, it is a space for the cartridge head (the original term for what we now call the rim).

Using cartridges with thick or thin rims doesn't change the rifle's headspace. If we want to change the rifle's dimensions, we have to adjust, modify, or replace something on the rifle. If my L-E rifle's headspace is .067", that dimension remains the same whether my cartridge rims are .064" or .054" thick - or even if I file off the rim completely and let the cartridge stop on the shoulder.

http://telecom.hartford.edu/images/303rimless20.jpg

Many people today say "headspace" when referring to the difference between the actual rifle headspace and the cartridge rim thickness, but this is technically imprecise. The "slop" occurring when the rim is thinner than the space provided in the rifle is more precisely called "cartridge end-play" - or sometimes "head clearance".

http://i41.tinypic.com/2v2gswz.jpg
Headspace and head clearance (cartridge end-play) are different animals.

Fortunately, the .303 cartridge has a sturdy little shoulder, and after fireforming we can use it to control end-play while disregarding the rim - just as we do with rimless designs.

[Edward Horton]

Parashooter, cartridge case manufacturing standards and headspace settings are NOT misconceptions, Remington and Winchester do NOT make .303 British cartridge cases to British Military specifications. Not only are the manufacturing standards different on American .303 cases, the SAAMI headspace standards are also different from British military standards.

Therefore headspace is governed by the cases you shoot and not the rifle, if a Winchester case stretches .009 thousandths in my 1943 Maltby with the headspace set at .067 and a Greek HXP and Prvi Partizan cases do not stretch or thin in the web area in the same rifle then "something" in their case construction IS different.

Given the fact that I actually measure my cases before and after shooting them and you do not, means your very comments here are in question.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP4513.jpg

Also given the fact that you are still greasing your cases for your tests and postings, the information you are posting here is more than questionable and your entire premise behind your "Headspace 101" is flawed and defective with your "testing" methods.

The British "Textbook of Small Arms" tells you to keep your cases and chamber grease and oil free.

The United States Military tells you to keep your cases and chamber grease and oil free.

The ammunition manufactures tell you to keep your cases and chamber grease and oil free.

The reloading manufactures tell you to keep your cases and chamber grease and oil free.

And you told everyone to grease their cases for over six years in your "Headspace 101" when they fire formed their cases, which then double the bolt thrust on everyones Enfield rifle who used YOUR "Headspace 101" information.

http://i122.photobucket.com/albums/o254/bigedp51/boltthrust.jpg

And YOU want to talk about misconceptions.

From a reloading manuals.

http://i122.photobucket.com/albums/o254/bigedp51/scan0048a.jpg

http://i122.photobucket.com/albums/o254/bigedp51/oil-lube.jpg

From the firearms manufactures.

http://i122.photobucket.com/albums/o254/bigedp51/oilcover.jpg

http://i122.photobucket.com/albums/o254/bigedp51/oilinchamber.jpg

Military warning about oil and grease on ammunition and in your chamber.

http://i122.photobucket.com/albums/o254/bigedp51/dontlube-1.jpg

http://i122.photobucket.com/albums/o254/bigedp51/lube-2a.jpg

What is "technically imprecise" Parashooter is YOU greasing your cases to get YOUR results and then wanting to nitpick someone else's posting about headspace and head gap clearance.

Below is your own animated .gif image Parashooter showing a .303 case stretching when being fired from YOUR "Headspace 101" and YOU told everyone to grease their cases to prevent their cases from stretching.

http://i122.photobucket.com/albums/o254/bigedp51/headspacestretch-1.gif

Now you were saying something about misconceptions Parashooter............

With a rubber o-ring around the base of the case you have zero headspace and zero head gap clearance no matter how nitpicky you are and you don't need to lube your cases.

http://i122.photobucket.com/albums/o254/bigedp51/headspacestretch_frame_0001.jpg

[Parashooter]

Well, Ed, I see you're still tending to uncontrolled ranting when someone points out a possible flaw in one of your posts. I sure wish you'd try to control that behavior on these forums. It's sad that you've chosen not to; you've done heaps of very good work on these subjects but it sometimes gets lost in the explosions.

Stated as simply as possible, you have made the very common error of confusing headspace with cartridge end-play. Simply substitute "end-play" for "headspace" in those parts of your first post on this topic that deal with the remaining unoccupied space between barrel and bolt face when a cartridge is in the chamber and there's very little to quibble about - except maybe the assertion that US .303 cartridges are loaded to lower pressure than "British military standards". Could be true or not - I don't have the tools or resources to know for sure. Do you?

Nobody participating in this topic said a word about case lubrication - until you chose to go off on that overworked tangent. I suspect we'd all have a better time if you gave it a rest unless it's actually being discussed.

Come on, Ed. I know you can be better when you want do.

[Edward Horton]

That wasn't a uncontrolled rant, I have been telling you for over six years that you are wrong and you decided to get your little zinger in about a "possible flaw" in my posting.

If you were never wrong Parashooter then why did you change "Headspace 101" from telling people to lube their cases to using weed whacker cord and dental floss to wrap around their cases. The original o-ring idea was posted at the old Jouster forum by a Canadian and we both read his posting.

Once the case is fired using the o-ring method without grease, lube or oil on the case or in the chamber the word headspace becomes meaningless.

http://i122.photobucket.com/albums/o254/bigedp51/fireformed-zeroheadspace.jpg

And Parashooter even the European CIP the equivalent of SAAMI in the U.S. claims the .303 British has "problematic headspace" for the cartridge cases being manufactured.


Delta L problem or "One size doesn't fit all"

Many times I have said something was wrong with our American .303 British cases now even the European CIP seems to agree.
("practical incompatibility with ammunition made for the corresponding chambering")

Delta L problem

The delta L problem (ΔL problem) is a condition that occurs regarding certain firearms chambers and their practical incompatibility with ammunition made for the corresponding chambering. The ΔL refers to a Commission Internationale Permanente (C.I.P.) geometric dimensioning and tolerancing definition for firearms cartridge cases which are longer than the chamber they have to fit in.

Conflicting industry standards

The main cause for the ΔL is that the two main civilian ammunition and firearms industry standards organizations C.I.P. and SAAMI have assigned different standards for the same cartridges. This leads to officially sanctioned conflicting differences between European and American ammunition dimensions and chamber dimensions. Since C.I.P. and SAAMI do not rule nor control civilian ammunition standards worldwide other causes for conflicting standards leading to ΔL issues are also possible.

Firearm cartridges with otherwise problematic headspace

There are also some firearm calibers with problematic headspace listed by C.I.P.[2]
The headspace defined by:
Depth of rim recess
.303 British
.38 Sp AMU
6.35 Browning
7.65 Browning
9 mm Browning long

http://en.wikipedia.org/wiki/Delta_L_problem

Parashooter, this means:

"Headspace is determined by the type cases you shoot and not the rifle."

2002 Canadian headspace standards for the No.4 Enfield rifle.

.064 GO
.070 NO-GO
.074 FIELD MAX

http://i122.photobucket.com/albums/o254/bigedp51/Canadianheadspace.jpg

Here Endeth Today's Lesson Parashooter...(from published facts and NOT myths or assumptions)

"Come on, Ed. I know you can be better when you want do"

Parashooter, when you make postings telling me I misspelled a word or I don't know the difference between headspace and head gap clearance its more than just nit picking. You decided to make it personal in this posting because YOU don't like being wrong and decided to get even with your comments which were not needed or called for.

My personal rant Parashooter is garbage information shouldn't be handed out in forums when you have NO official printed data to back up your incorrect assumptions. ;)

Below from the 1929 British War Office Manual the "Textbook of Small Arms" on the Enfield rifle.

http://i122.photobucket.com/albums/o254/bigedp51/oilpressstrain.jpg

Your telling everyone to lube their cases is more than a little "possible flaw" in your postings and your own "misconception" in "Headspace 101" Parashooter.

On top of this you can check Enfield headspace with an unfired case and a set of feeler gauges, by placing the feeler gauge between the receiver and the right locking lug.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6598b.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6601.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6600.jpg

Add the feeler gauge thickness to your rim thickness and you have your Enfields headspace setting.

Goodbye Parashooter I'm going on a weeks vacation, I'm meeting the Dalai Lama and we are going to reach headspace Nirvāna..................

[Bindi2]

I have been reloading the 303 for more than 40 years and have never had a hadspace problem to cure shooting 50 to 100 rounds a week. I do have problems with rubbish cases separating as low as the second fireing. They all came from the same country which appears to have this headspace phobia. Buy the proper mil spec guages find the real problem and fix it. ED did and has.

[Edward Horton]

Just a little clarification from the British War Office in 1929.

http://i122.photobucket.com/albums/o254/bigedp51/TBOSA-1.jpg

http://i122.photobucket.com/albums/o254/bigedp51/TBOSA-2.jpg

I took a 0 (zero) bolthead and lapped the bolt head (wet sanded it on a piece of glass) and set the headspace on one of my Enfields at slightly over .084 or .010 over maximum headspace.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6471.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6472.jpg

Using the rubber o-ring method of fire forming cases with the case being held firmly against the bolt face I fired factory loaded and my reloads with absolutely no ill effects.

Using the rubber o-ring to fire form your cases makes the word headspace meaningless with the Enfield rifle, without worrying about case head separations and excess bolt thrust from oiled or greased cases.

Below in the top photo is a South African 1982 military surplus .303 ammunition resting in a Wilson case gauge. The American made Wilson gauge is nothing more than a "American" SAAMI .303 chamber. The South African made .303 round is .002 below the gauge markings as it should be.

In the bottom photo is a new unfired Remington case and it is over a 1/4 of an inch short of where it should be in the gauge. (American made .303 British ammunition is NOT made to British military standards)

http://i122.photobucket.com/albums/o254/bigedp51/twocases.jpg

American made commercial .303 cases were not designed to British military standards and fall apart quickly when reloaded at over 43,000 CUP.

http://i122.photobucket.com/albums/o254/bigedp51/shoulder-a.jpg

The best cases you can presently get for your .303 British Enfield are Prvi Partizan cases, they ARE made military heavy duty and will last much longer. In another forum one member did a destruction test after fire forming his cases with the rubber o-ring method and got over 30 reloads before the first case failure.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6206.jpg

Below a Prvi Partizan case reloaded 3 times, the rims are thicker, the base diameter is larger and the case walls are thicker than ANY American made .303 British ammo.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP5058.jpg

Headspace is governed by the cases you shoot and NOT the rifle.

[Jim K.]

The NO-GO is the wrong gauge for checking headspace on a used rifle. The GO and NO-GO gauges are used by factories and gunsmiths when installing a barrel or a bolt. The proper gauge for checking out headspace on a used rifle is the FIELD GAUGE, which takes into account a reasonable amount of wear. Almost any rifle that has seen much use will accept a NO-GO gauge and falsely indicate a dangerous condition.

Jim

[Edward Horton]

The NO-GO is the wrong gauge for checking headspace on a used rifle. The GO and NO-GO gauges are used by factories and gunsmiths when installing a barrel or a bolt. The proper gauge for checking out headspace on a used rifle is the FIELD GAUGE, which takes into account a reasonable amount of wear. Almost any rifle that has seen much use will accept a NO-GO gauge and falsely indicate a dangerous condition.

Jim

When buying a new Enfield the first gauge I use is the .067 gauge.

When proof tested the Enfield had its headspace set as close to .064 as possible, after the oiled high pressure proof round was fired the Enfield was checked with a .067 headspace gauge. If the bolt closed on the .067 gauge the Enfield developed too much lug setback and failed proof testing.

All my Enfields that are new, low mileage or have gone through an FTR have headspace below .067 and were untouched by me.

The book below by Ian Skennerton tells you to set your Enfield headspace .003 over your rim thickness.

http://i122.photobucket.com/albums/o254/bigedp51/cover-a.jpg

The Mk.2 below has two bolt heads fitted, the original at below .067 and a newly lapped bolt head with the actual headspace set at slightly below .062. The rim thickness of my Remington and Winchester cases are around .058-.059 and this give me .003-.004 head gap clearance.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP1355-1.jpg

These are the headspace gauges I use to check an Enfield.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP5264.jpg

American made commercial cases are NOT made to British military specifications and have lower or tighter headspace limits.

Headspace is governed by the cases you shoot and NOT the rifle and this is why American cases do not last as long when reloaded. On top of this American .303 commercial cartridges are loaded to LESS than 43,000 CUP to ensure they are safe to shoot in all .303 models. The original .303 smokeless cartridges were loaded to 16.5, 17.5 and 18.5 tsi and this why the American factories load the .303 to pressures lower than the last rated cartridge pressure of 18.5 tsi or 46,000 cup for the .303 British.

If you use the .074 headspace gauge and American made cases you can have as much as .020 head gap clearance or air space between the bolt face and the rear of the case. And this is what causes case head separations unless the cases are properly fire formed.

If you haven't noticed the people who say the least about headspace are shooting military Greek HXP ammunition, and the people who complain the most are shooting American made cases.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6195.jpg

[John Sukey]

Hey Ed. I have that brace and screwdriver bit for removing stock bolts.

[Edward Horton]

Mr. Sukey

The same book shows all the older No.1 Armourer tools.

Photo from above book of an older No.1 Stock Collar Gauge/filing jig.

http://i122.photobucket.com/albums/o254/bigedp51/collargauge-a.jpg

And my Canadian made No.4 Stock Collar Gauge/filing jig

http://i122.photobucket.com/albums/o254/bigedp51/IMGP2147.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP2148.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP2149.jpg

[DaveP]

Hi, guys. You all seem to know about this problem. I don't. I have a #5 carbine made at Fazakerley, and I have trouble chambering rounds prior to firing. I have to force the bolt closed. After firing I really have to force the bolt to open. Sometimes I have to whack the bolt handle against some immovable object to move the bolt to the rear. Needless to say the cases are all scratched up. Is this a headspace problem or something else? I'm using Australian military ammo from the 80's. I used to have a 1915 dated #1 MkIII* and had no such issue. The action was as smooth as butter-and fast. I know enough about guns not to fire this one until whatever this problem is gets corrected, but since I live in NYC, finding a gunsmith might be a problem. Any input is appreciated.

[Edward Horton]

DaveP

1. Move out of NYC (my son did) :icon_lol:
2. As closely as possible examine your chamber for defects, corrosion, embedded material in chamber walls, and possibly the remains of a case that separated near the shoulder.

The .303 Enfield military chamber is "longer" than a civilian SAAMI chamber to allow room for the mud of Flanders at the shoulder area of the chamber. The chamber also has a larger diameter neck area than standard civilian commercial chambers. This leaves ample room for "excess" garbage that doesn't belong in the chamber and could explain your hard chambering.

Posting photos of your scratched and damaged fired cases would be a good starting point for our long range psychic repair of your Enfield rifle. ;)

http://i122.photobucket.com/albums/o254/bigedp51/303deawingjpg.jpg

http://i122.photobucket.com/albums/o254/bigedp51/303drawing-2.jpg

[Parashooter]

The .303 Enfield military chamber is "longer" than a civilian SAAMI chamber to allow room for the mud of Flanders at the shoulder area of the chamber. The chamber also has a larger diameter neck area than standard civilian commercial chambers. This leaves ample room for "excess" garbage that doesn't belong in the chamber and could explain your hard chambering.

http://i122.photobucket.com/albums/o254/bigedp51/303deawingjpg.jpg


If the above drawing dimensions are accurate, the accompanying statement is not. Examination of SAAMI .303 chamber dimensions shows that neither the overall length, head-shoulder distance, nor the neck diameter are smaller than the dimensions given in "Fig. 3".

http://telecom.hartford.edu/images/303saami.gif
SAAMI .303 drawing

[Edward Horton]

Parashooter

Please read this very carefully and try and remember what I say and show you here this time, this is the third time you have doubted my statements on the very same subject.
(You need to get some gauges)


Below is a box of Remington .303 ammunition, and one factory cartridge is resting in a Wilsons case gauge. The Wilson case gauge is used to adjust your reloading dies for bumping the shoulder back to approximately .001 to .002 smaller than actual chamber headspace for ease of chambering and still not over resize the case.

The .303 cartridge below is resting on the shoulder of the case and it is .002 below the top of the gauge and is correct for a newly manufactured American SAAMI cartridge case.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP5198.jpg

Pictured below is a 1981 South African Military surplus .303 cartridge resting on its shoulder as the Remington case above. Both cartridges meet American SAAMI and European CIP standards.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6318.jpg

Below is the same South African ammunition after being fired, the amount the case is sticking above the gauge is how much longer or deeper the British military chamber is compared to a civilian SAAMI chamber.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP6321.jpg

All the drawings of the .303 British chamber on the Internet and pictured here predate the modifications done to the Enfield chamber during WWI and subsequent manufactured Enfield rifle chambers.

The bottom line is the military Enfield chamber is longer than commercial standards and our American reloading dies over resize the .303 cases and push the shoulder back too far by approximately an 1/8 of an inch.

Parashooter, the fired shoulder is so far forward after firing I'm using a .303 case forming and file die as a shoulder bump die to push the shoulder back for easier chambering.

Shown below the cases can be inserted and removed with just your fingers, "BUT" when used in the reloading press and adjusted properly the shoulder can be bumped back .001 - .002.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP7098.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP7099.jpg

So "YES" Parashooter the drawings are off and my statements are dead on the mark as usual. :icon_wink:

Also to add insult to injury for the last six years Remington and Winchester cant make up their minds of where to put the shoulder of newly manufactured cases. In the bottom photo below a brand new Remington case is approximately 1/4 of an inch too short.

http://i122.photobucket.com/albums/o254/bigedp51/twocases.jpg

Below the red lines show how far off the shoulder location is off on new cartridge cases made by both Remington and Winchester. No wonder they fall apart after three reloadings with this type of quality control

http://i122.photobucket.com/albums/o254/bigedp51/shoulder-a.jpg

[Parashooter]

If the "Fig.3" drawing is wrong, why post it?

http://telecom.hartford.edu/images/303samples.gif
My unfired Remington cases have their shoulders in the same place as British and South African military ammunition. Maybe you got rejects. Anyway, we both know the initial location of the shoulder is immaterial if the case head is held against the bolt face when first fired, so why fuss about it?

http://i122.photobucket.com/albums/o254/bigedp51/twocases.jpg
Do you really think this is "approximately 1/4 of an inch too short"? Time to buy a little ruler - or calibrate your eyeballs.

Come on, Ed, I know you can do better!

[Edward Horton]

Parashooter

I posted figure 3 because the majority of forum members aren't as crabby, picky and anal retentive as you are. ;)

I posted the photo because I don't need your permission to post a photo from a old British manual.

And I don't need to do better if the rim of the case is hitting internally on the case gauge. What you need to do Parashooter is recalibrate your attitude.

http://i122.photobucket.com/albums/o254/bigedp51/IMGP7160.jpg

And you of all people Parashooter should know the case head is "NOT" held against the bolt face when first fired. (unless you lube your cases to prevent them from gripping the chamber walls and double the bolt thrust like you do Parashooter) :eek:

http://i122.photobucket.com/albums/o254/bigedp51/headspacestretch-1.gif

This forum or any forum isn't "your" classroom Parashooter and your entire "Headspace 101" is based on greasing cartridge cases when the whole world tells you not to.

http://i122.photobucket.com/albums/o254/bigedp51/dontlube.jpg

Do you actually think you are smarter and know more than the entire firearms community with all their engineers and pressure measuring test equipment.

I don't want to use your ruler Parashooter because its too far out of calibration. ;)

[Parashooter]

OK, I could be wrong - you apparently can't do better anymore. That's too bad, because you have a lot to offer when you can climb off the soapbox, stop playing the clown, and act like the rational person with whom I used to have spirited and worthwhile discussions.

[Edward Horton]

You "ARE" wrong Parashooter, your posting here has "NOTHING" to do with the question DaveP asked about his No.5 Enfield. And you want to argue about a 100 year old British military photo and make the statement that the information I provided was wrong...........

"If the above drawing dimensions are accurate, the accompanying statement is not"

Don't play games here Parashooter, you know the Enfield chamber was enlarged and reamed out in WWI and doesn't comply with SAAMI standards because the SAAMI didn't come into existence until 1926.

On top of this the American SAAMI or the European CIP does "NOT" regulate military cartridge or chamber dimensions.

And the only "clown" here is you Parashooter trying to be cute and start an argument over a British photo and American commercial SAAMI chamber dimensions that do "NOT" apply to the British military Enfield .303 rifle.

[John Sukey]

QUOTE=Edward Horton;81195]Mr. Sukey

The same book shows all the older No.1 Armourer tools.

Photo from above book of an older No.1 Stock Collar Gauge/filing jig

http://i122.photobucket.com/albums/o254/bigedp51/collargauge-a.jpg

And my Canadian made No.4 Stock Collar Gauge/filing jig

http://i122.photobucket.com/albums/o254/bigedp51/IMGP2147.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP2148.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP2149.jpg[/QUOTE]

Ed, you're not the only one with that tool, I have one as well:icon_wink:
Also a set of bore gages.

[MJ1]

So Ed do you use the O-ring on every firing or just the first?

[Edward Horton]

So Ed do you use the O-ring on every firing or just the first?

MJ1

I use the rubber o-ring method once or twice on reduced loads fire forming the cases and then there after the o-ring is not needed because the case is head spacing on the shoulder and not the rim of the case.




http://i122.photobucket.com/albums/o254/bigedp51/IMGP2717-a.jpg

http://i122.photobucket.com/albums/o254/bigedp51/IMGP4691.jpg

http://i122.photobucket.com/albums/o254/bigedp51/fireformed-zeroheadspace.jpg