enfield head spacing

[JTF#]

I hear allot of people talking about head spacing on the lee enfields. my question is how do you know if the gun is out of head space? like if you take the gun out to shoot it how would you know? without checking it first.

 

[louthepou]

Really streched cases or even ruptured cases (rupturing near the head) are a hint.

 

[rgallant]

You can do a quick and dirty check if you don't mid cutting up and old feeler gauge and have a micrometer.

Get a snap cap or any other non live 303 round that chambers

Measure the rim

I had a dummy round, rim was around .06

I went with field .074 so I chopped down a .014 feel gauge

dropped the dummy in the chamber, muzzle down put the feeler gauge piece on top.

Closed the bolt and gently - no real pressure tried to rotate to close the action, it did not close I am at about .071 or so.

So good to go, all most no case expansion after firing which was nice.

Remember rimmed cartridges headspace differently from non rimmed.

 

[ryan]

No need to worry about headspace. If it's excessive, like lou says, case rupture or stretching may occur, neither will blow up a Lee enfield. If the rifle shoots fine, all is good.

 

[JTF#]

okay thanks. . I'm mostly into No1s and I heard that to headspace them you actually have to file away some of the bolt head. not something I wanted to do.

 

[migrant hunter]

I did a really hillbilly version and stuck masking tape on the head of an empty shell, then cut around it with a knife. I kept adding layers till I could feel it snug when I closed the bolt. Remove the tape layers all in one peice and measure with a caliper.
The hard part is finding a bolt head the right size as the 0,1,2,3,4 heads vary wildly according to where they were made.

 

[bigedp51]

A very simple simple headspace check can be done with a new unfired case or a case that has been full length resized. Meaning the cases are head spacing on the rim and not the shoulder of the case which would give you a false reading.

You chamber the empty case and with a feeler gauge you measure the "head clearance" or the "air space" between the bolt face and the rear of the case.

You can do this headspace check with the bolt dissembled to make it easy or with the bolt assembled and pushing hard on the bolt handle. By pushing the bolt forward you are making contact with the bolt face and the rear of the case and this allows you to measure your head clearance at the right locking lug and the receiver.

Below when pushing on the bolt handle your head clearance can be measured externally between the arrows as the gap between the right locking lug and the receiver.

Below keep increasing the feeler gauge thickness until you find the largest blade thickness that will fit in the gap between the right locking lug and the receiver.

The average American commercial SAAMI case has a rim thickness of .058 and if your feeler gauge reading is .016 you are at the maximum military headspace of .074.

Below the feeler gauge would be measuring your "head clearance" and when you add this to your rim thickness you have your actual headspace reading.

Note, I ran headspace tests with the bolt face just kissing the rear of the case (under .064 headspace minimum) with Remington cases that have slightly thicker case wall thickness in the base of the case than Winchester cases. To the Emergency Wartime Headspace setting of .084 (.010 over normal military maximum) with little to no stretching in the base web area of the case. Meaning you would have to have some very thin brass or headspace settings "over" .084 to cause a case head separation on the first firing. The best brass you can get today is Prvi Partizan .303 cases, they have a larger base diameter, thicker case walls in the base of the case and thicker rims than any other commercial case made today.

 

[W.R.Buchanan]

Big Ed: Excellent write up! Thanks, that is a valuable tool in assessing condition before buying a gun that is easy to do in the field.

Randy

 

[bigedp51]

Big Ed: Excellent write up! Thanks, that is a valuable tool in assessing condition before buying a gun that is easy to do in the field.

Randy

I have .303 British headspace gauges, "BUT" all they tell you is if the bolt handle will close on the gauge. Using the feeler gauge method you should be within .001 of actual headspace, depending on your "feel" when using the feeler gauges.

A second method of checking your headspace is to use a new or full length resized case again, making sure the case is headspacing on the rim. You place a fired spent primer in the primer pocket just using your fingers to seat the primer.

Step 1. Measure the case length and write it down.

Step 2. Place a fired spent primer in the primer pocket just using your fingers.

Step 3. Chamber the case and slowly close the bolt fully using the bolt face to seat the primer and then eject the case.

Step 4. Now measure the case again and write it down.

Step 5. Subtract the first case measurement from the second case measurement, the answer is your head clearance or the "air space" between the bolt face and the rear of the case.

Step 6. Add your rim thickness to your head clearance and you have your actual headspace measurement.

It doesn't matter what type case you have, rimmed, belted or modern bottle neck case, it is the head clearance that causes case head separations.

Below the head clearance controls how far the case must stretch to meet the bolt face when fired. And when this distance is too great you over stress the brass past its elastic limits and the brass will stretch and thin in the base web area.

 

[sunray]

Proper headspace gauges are the only way to check headspace. Bits of tape and anything else mean nothing. Headspace gauges only tell you if the headspace is within spec. They don't measure anything. Headspace is a manufacturing tolerance, period.
The bolt is supposed to close on a Go, but not a No-Go and absolutely not on a Field. Indicati9ons of excessive headspace include excessively stretched case and, in extreme cases, ruptured cases, but also hard extraction and difficulty opening the bolt.
Head clearance is irrelevant to headspace. It ain't the same thing. How a rifle shoots has nothing to do with headspace either.
No. 1's are headspaced by changing bolt heads and checking with gauges until you find one that is good. No filing involved. Problem is the bolt heads are not numbered like No. 4 bolt heads. Means you need a handful at least $20 each.

 

[W.R.Buchanan]

ED: Thanks and I will be doing both my guns this afternoon just to see what I've got. I know they are both OK but I want to see Exactly what I've been working with.

I see three methods here and since I do all my gun work in my machine shop I just bet I could make those head Space gauges.

I also am going to make some for belted cartridges as I have a 03A3 that has been converted to .308 Norma Magnum and I want to make sure it was done right.

Thanks for the info.

Randy

 

[Tinman204]

Proper headspace gauges are the only way to check headspace. Bits of tape and anything else mean nothing. Headspace gauges only tell you if the headspace is within spec. They don't measure anything. Headspace is a manufacturing tolerance, period.
The bolt is supposed to close on a Go, but not a No-Go and absolutely not on a Field. Indicati9ons of excessive headspace include excessively stretched case and, in extreme cases, ruptured cases, but also hard extraction and difficulty opening the bolt.
Head clearance is irrelevant to headspace. It ain't the same thing. How a rifle shoots has nothing to do with headspace either.
No. 1's are headspaced by changing bolt heads and checking with gauges until you find one that is good. No filing involved. Problem is the bolt heads are not numbered like No. 4 bolt heads. Means you need a handful at least $20 each.

For the 1000th time,

Headspace CAN be measured WITHOUT gauges on a rimmed cartridge!!!

OP please disregaurd the quote above and follow Ed's instructions!!

There's 100's if not 1000's of us on here who don't have gauges and yet Ed's method works for us.

 

[englishman_ca]

One shot brass

Sunray needs HIS headspace checked.

If you do a ton of shooting, and want to reload (to save cost), find a tighter chambered rifle. Save yourself some headaches.

OR use new commercial cartridges (mil surp ammo has all but disappeared from the stores) and toss the empties into a bin and worry about reloading later. Headspace was never of great concern with Enfield shooters when there were buckets of surplus ammo for sale.

When these rifles were designed, the brass was a one shot and one shot only. It is later day civilian users who reload and must address the challenges of stretching, sizing, workhardening, anealing. Not a major problem if you segregate used brass to a specific rifle. It will be fire formed to the chamber, it can be reloaded by just resizing the neck where the bullet fits. The dedicated brass will last many reloads if treated right.

There is a whole science to reloading. Even more so with the Lee Enfield. There is a lot of information and miss-information floating about. It can get complicated if you let it. The info you find is in effect just work arounds for reloading and reusing a disposable cartridge case.

Or, you can keep it simple, just buy fresh ammo and enjoy shooting the thing.

 

[bigedp51]

Proper headspace gauges are the only way to check headspace. Bits of tape and anything else mean nothing. Headspace gauges only tell you if the headspace is within spec. They don't measure anything. Headspace is a manufacturing tolerance, period.
The bolt is supposed to close on a Go, but not a No-Go and absolutely not on a Field. Indicati9ons of excessive headspace include excessively stretched case and, in extreme cases, ruptured cases, but also hard extraction and difficulty opening the bolt.
Head clearance is irrelevant to headspace. It ain't the same thing. How a rifle shoots has nothing to do with headspace either.
No. 1's are headspaced by changing bolt heads and checking with gauges until you find one that is good. No filing involved. Problem is the bolt heads are not numbered like No. 4 bolt heads. Means you need a handful at least $20 each.

Sunray

Headspace is also the distance between your ears and how you use the gray matter in between........................why don't you try using your head for something other than a hat rack.

Second, number 1 bolt heads were sanded/lapped for the proper headspace settings and the longest bolt heads were marked with a "S" for spare.

Third, head clearance "IS" part of your headspace and it controls how much the cases will stretch when fired.

Instead of flapping your lips on a subject you know very little about why don't you read the Enfield rifles "Instructions for Armourers" on how bolt heads were fitted.

 

[Tinman204]

Sunray

Headspace is also the distance between your ears and how you use the gray matter in between........................why don't you try using your head for something other than a hat rack.

Second, number 1 bolt heads were sanded/lapped for the proper headspace settings and the longest bolt heads were marked with a "S" for spare.

Third, head clearance "IS" part of your headspace and it controls how much the cases will stretch when fired.

Instead of flapping your lips on a subject you know very little about why don't you read the Enfield rifles "Instructions for Armourers" on how bolt heads were fitted.

I just spit my coffee out!!

Than you Ed!!!!

 

[bigedp51]

Head clearance is irrelevant to headspace. It ain't the same thing. How a rifle shoots has nothing to do with headspace either.

Headspace, specifically "head clearance" effected the Enfield rifles accuracy at longer ranges. This was due to bolt thrust, the rear locking lugs and the receiver flexing causing horizontal stringing. Fulton of Bisley England accurized Enfield rifles for long range shooting and many of these rifles had the headspace adjusted to where the boltface was just barely touching the rear of the case. These Enfield rifles had two bolt heads fitted for varying cartridge rim thicknesses.

And sunray "SOME" of us have studied the Enfield rifle for a very long time and know what we are talking about.

And people like you could fly a hot air balloon without a gas bottle and burner and set the world altitude record.

 

[tootall]

Subscribed!

 

[W.R.Buchanan]

Ed I did my #4 Mk1* Longbranch Parker Hale Sporter today and came up with .066. .063 PPU rim thickness and .003 primer protrusion.= .066. nice tight gun that is getting bored out to .35-.303 soon.

Thanks for the tip I don't have to make headspace gauges now.

Randy

 

[boltonscouter]

Ed ....... many thanks for the primer method also! Worked like a charm! I have two rifles (a No1 & a No4) I have always thought the headspace was fine on but never really knew for sure. Turns out with .060" rim thickness Winchester brass I have .003" primer protrusion on one rifle and .004" primer protrusion on the other !!! .063" & .064" ...... VERY happy & thanks again!

Sunray ......

 

[Remiel]

Thank you for the information, I am helping a friend rebuild a #4 mk1 and this information has save a lot of time and head scratching.