Lee enfield headspace

[351 WINCHESTER]

I've heard that over time the lee enfields action streaches requiring a larger bolt head.

How does one know when to replace the bolt head and does anyone know how many standard rounds can be fired before headspace becomes an issue?

I'm talking about a no. 5 and a no. 4.

I want to shoot these, but I don't want to abuse them.

 

[nathan]

I think thats the weakness of the design . No doubt, Its the fastest cycling bolt action rifle but in time the erosion and stretching will erode headspace and so it needs to be check once problems occur.

 

[Aren't we all]

The lee enfield design is a very interesting one. The design is not as strong in the locking lugs for rate and ease of bolt manipulation. When hundreds of rounds are fired in a Lee Enfield the headspace is increased by the repeated percussive forces of the cartridge on the bolt. Signs of bad (too much) headspace are few, such as neck expansion, gas escape,case head seperation etc. It would be a good idea to get a coin type headspace gauge to measure the headspace visually, and probably the cartridge type gauges as well. As to the bolt heads the No 1 does not have numbered bolt heads for ease of headspacing, but the No 4/5 do. Many of these guns have had thousands of rounds of full pressure millitary loads throught them over the years, use downloaded cast lead bullets and you should probably never have a headspace problem.
Reading materials
http://parallaxscurioandrelicfirearmsforums.yuku.com/topic/3361/t/Headspace-101-for-303-s.html



Marsh

 

[briansmithwins]

The headspace can change with time. I suspect nearly all of that change is going to be due to wear and not the action stretching.

I'm not sure (don't have any documentation) but I think you're going to shoot out the throat of the barrel before headspace becomes excessive. Assuming it was good to start with. BSW

 

[nathan]

If you want a pristine No 4, the mummy wrapped Fazakerleys are out there for a hefty price. Guaranteed they are basically new and unfired.

Most of those NO 4 out there are quite worn and headspace ok , but its no guarantee it will stay that way. A few hundred rounds and excessive headspace comes out. Remember most are 80 yrs old or less and had been fired many many times by different owners.

 

[DougW]

Wow! Lots of things going on here. Maybe a bit of clarification is in order.

1) The action on the #1 and #4 rifles do not "streatch" with time. Corrosion and erosion change headspace. But, first you need to know that the Enfields don't headspace on the case neck. They space on the case rim. The chambers are loose on purpose to handle battlefield conditions, which no one will ever say an Enfield did not do. So, if they headspace on the rim, case streaching is probable. Happens on all mine.

2) The locking lugs are on the rear of the bolt, and are from the older black powder days. The action is fast, but not as strong as a front locking lug bolt. The military loading for the .303 is not quite as high as the 30.06, bacause the Enfield locking system would be overstressed with the higher pressure loadings. But, it fires close to 30.06 velocity. Why do you think the Brits put 8 Browning .303's in the Spitfires and 6 in the Hurricanes if it is so inferrior?

3) I have 14 various Enfields in .303. These rifles date from a 1917 BSA #1mkIII to a 1950 Ishapore #1mkIII, with lots of #4mk1's, #4mk1*'s, a pair of #5mk1's, and a Pattern 14 (#3mk1), and the headspace varies from real tight to maybe a bit loose. None exibit the "classic" headspace issues, some of the rifles having been fired hundreds of times by me with milsurp and my reloads (the Pattern 14 is a Mauser action, and it locks up tight!). These rifles are not worn out, and I am not having to constantly adjust the headspace by swapping the boltheads on the #4's and #5's (something you CANNOT do with a #1mkIII). Wear and tear don't streach the reciever, unless you are shooting 10,000+ rounds.

4) If you want to have some real fun, grab a bunch of different .303 cartridges and put a caliper on the base. You will be surprised how much variation there is on the case heads. And, none will approace the thickness of an actual Military Headspace Gauge, which is thicker than a SAAMI gauge. The SAAMI Field gauge is close to the Military No-Go. So if you throw in some good old SAAMI headspace gauges and your rifle looks good, what happens when you put in a thinner cartridge? Your headspace goes out the window. Now what do you do?

Yes, the Enfield rear locking lug is weaker than a front locking lug Mauser or similar design. But, the rifle is not inferrior to it's contemporaries. Will not shoot quite as fast as an M1 Garand, but it holds more rounds, and more rounds than a Mauser, Arisaka, or Carcano, which means more sustained fire. But then, the Enfield's and Garand's fought together. Don't fear the Enfield. If you do, then send it to me freight paid with a $10 disposal fee, and I will take care of it for you!

 

[351 WINCHESTER]

I have a great deal of respect for these old battle rifles. I appreciate everyones's comments. I like to shoot mine, but someone told me that if I shot it much I would be changing bolt heads.

I reload ammo for mine and stick with the mid range stuff because it's easier on my aching shoulder and my brass too. I guess the old girl will be around for another half century or so.

 

[jd70]

I've owned a #4 fazakersly for the last ten years. Bought it used and the first time I shot it excessive head space. Took her to a good gunsmith I know and he simply welded up then ground it back to the next correct head size. It's worked great ever since.

 

[madcratebuilder]

Wow! Lots of things going on here. Maybe a bit of clarification is in order.

1) The action on the #1 and #4 rifles do not "streatch" with time. Corrosion and erosion change headspace. But, first you need to know that the Enfields don't headspace on the case neck. They space on the case rim. The chambers are loose on purpose to handle battlefield conditions, which no one will ever say an Enfield did not do. So, if they headspace on the rim, case streaching is probable. Happens on all mine.

2) The locking lugs are on the rear of the bolt, and are from the older black powder days. The action is fast, but not as strong as a front locking lug bolt. The military loading for the .303 is not quite as high as the 30.06, bacause the Enfield locking system would be overstressed with the higher pressure loadings. But, it fires close to 30.06 velocity. Why do you think the Brits put 8 Browning .303's in the Spitfires and 6 in the Hurricanes if it is so inferrior?

3) I have 14 various Enfields in .303. These rifles date from a 1917 BSA #1mkIII to a 1950 Ishapore #1mkIII, with lots of #4mk1's, #4mk1*'s, a pair of #5mk1's, and a Pattern 14 (#3mk1), and the headspace varies from real tight to maybe a bit loose. None exibit the "classic" headspace issues, some of the rifles having been fired hundreds of times by me with milsurp and my reloads (the Pattern 14 is a Mauser action, and it locks up tight!). These rifles are not worn out, and I am not having to constantly adjust the headspace by swapping the boltheads on the #4's and #5's (something you CANNOT do with a #1mkIII). Wear and tear don't streach the reciever, unless you are shooting 10,000+ rounds.

4) If you want to have some real fun, grab a bunch of different .303 cartridges and put a caliper on the base. You will be surprised how much variation there is on the case heads. And, none will approace the thickness of an actual Military Headspace Gauge, which is thicker than a SAAMI gauge. The SAAMI Field gauge is close to the Military No-Go. So if you throw in some good old SAAMI headspace gauges and your rifle looks good, what happens when you put in a thinner cartridge? Your headspace goes out the window. Now what do you do?

Yes, the Enfield rear locking lug is weaker than a front locking lug Mauser or similar design. But, the rifle is not inferrior to it's contemporaries. Will not shoot quite as fast as an M1 Garand, but it holds more rounds, and more rounds than a Mauser, Arisaka, or Carcano, which means more sustained fire. But then, the Enfield's and Garand's fought together. Don't fear the Enfield. If you do, then send it to me freight paid with a $10 disposal fee, and I will take care of it for you!

Finely, a post with correct information. The Brit .303 head space is .064 GO and .074 Field. If your rifle is about in the middle of that it well take thousands of rounds to wear the bolt lugs and receiver before you need to go with a longer bolt head. The bolt heads are numbered 0, 1, 2, and 3. Just getting a higher number head does not mean it well be longer. You need to measure these to be certain.

Here's a chart of numerous bolt heads and the measurements.

 

[MR]

Doug has it right.
The over size chamber tends to give the 303 a bad rap I had separations with light loads on the first reload, they didn't care how many times the brass was loaded. I set back a #4 barrel and the reamer barely cut. I want to re barrel but with a chamber cut with a custom reamer. WW and RP brass measures .450 as .455 for the SAMMI I have tried 30/40 Krag brass but it doesn't measure much bigger than 303.

mr

 

[Innovative]

The Brit .303 headspaces on the rim just like the 30-30 Winchester. The clearance at the rim needs to be correct when the barrel is installed or whenever the bolt is replaced. That clearance should should be minimal, and it will never change.

However, the main reason you're getting head separations is due to clamber clearance at the shoulder. This can happen with any rifle caliber. If you're handloading, the clearance "at the shoulder" should be measured. It's easily done by comparing your handloads to one of your fired cases.

A fired case is like the perfect casting of YOUR chamber, and it's easy to compare your handloads (at the shoulder) to that, and see exactly how YOUR handloads will fit. I designed the Digital Headspace Gauge to do exactly that, and it works on ALL different calibers. Check it out on my website.

- Innovative

 

[DougW]

Thanks Madcrate. These thisng will drive you crazy, especially when you start talking headspace. Inovative, you are correct sir. I segregrate all my brass to the rifle I fired it through. I usually avoid going to full length sizing unless I am trying out a different rifle. I usually only shoot my Fazakerley #4mk1 so that I don't have to work the brass so hard. Love them Enfields!

 

[351 WINCHESTER]

Thanks for all the info. I knew it headspaced on the rim, but I'm still dumfounded as how the headspace can change due to errosion. I'm assuming by errosion you are refering to the upper part of the chamber. If a rifle was fired say, 5K rounds the chamber would be erroded, but how does that effect the headspace?

It just doesn't make sence. If I took a reamer and reamed out the forward part of the chamber I still don't see how it would effect headspace. I understand that it would suffer from more strech of the brass and have more casehead seperations, but headspace should remain constant unless the bolt head or locking lugs become compressed or worn down.

 

[Innovative]

Think of it this way ..... when a rimless case (like the .308 Win.) has excessive chamber clearance at the shoulder, that actually is headspace. It's just being measured at the other end of the case.

Being that all rifle cases are tapered, it's always best to FL resize. Even benchrest shooters FL resize. However, it should be done accurately by bumping the shoulder back -.001" to -.002" at the most. You should not be able to "feel" the round chamber - not even a little.

- Innovative

 

[Curator]

One would think the "erosion" would be in the throat area, not the chamber. Headspace on the .303 british Lee Enfield is dependant on rim thickness of the case, the rim cut-out depth, and the bolthead. Unless there is considerable wear on the locking lugs of the bolt or very high pressure rounds fired to cause bolt set back "headspace" should be consistant. I have seen some bolt set-back from firing high pressure reloads with oily cases. Most Lee Enfiled shooters should know better than to shoot oily or wet cartridges.

 

[dogngun]

UES a set of neck sizing dies and don't worry about it.

I like the old Lee Loaders for .303 Brit and have loaded some very hot ammo with them...and I have never had any problems with cases separating in any of my 8 or so .303 SMLE's...and even the ones with terrible looking bores were pretty accurate shooters.

mark

 

[DougW]

dogngun makes a good point. I too only neck size my brass for my "shooter", only full length sizing for shooting different rifles.

I have had case head seperation on reloads using Sellier & Beloit brass. Primer pockets are shallow, and the cases only lasted 4 reloads max. I don't reload S&B anymore.

 

[Innovative]

Why FL resizing is best ...

Even shooters that neck size need to bump the shoulder back sooner or later. That's required for 100% reliable chambering. If you reload for one rifle only, it's best to have -.001" to -.002" shoulder clearance. Your FL die can resize the neck, bump the shoulder and "accurately" resize the tapered body in one operation ... while the case is aligned in a single die.

If you reload for more than one rifle, it's best to load spcifically for the tightest chamber, and you need to measure chamber clearance to resize FL accurately.

Lets say your handloads have -.005" chamber clearance (at the shoulder). That's considered acceptable. When you reduce the chamber clearance (at the shoulder) to -.001" you have reduced the amount of case stretching by 80%. That extends the life of your brass, and it can improve accuracy. Why not give yourself all the main advantages of handloading?

The concern of factory ammo is only for one shot, and the brass is perfectly soft and new. Handloading makes your brass brittle and much more apt to crack. The ammo factories have a rough idea of your chamber size, but YOU can know the "exact" size of your chamber to make the best handloads possible.

- Innovative

 

[DougW]

Innovative, that may apply to "conventional" shoulder headspacing, but headspacing on the case rim is a different issue. Once fireformed, the shoulder in the same rifle will not be moving. The case mouth may stretch, but proper sizing and trimming solve that problem. I have some Remington brass that has been reloaded 9 times (.303) and shows no sign of failing. It is fired throught the same rifle all the time.

Nice thing is that both of my #5mk1's will chamber the ammo neck sized for the #4mk1 Fazakerley, so extra working of the brass for me is not necessary.

 

[Innovative]

DougW ........

I fully understand cases that headspace on the rim, and I also understand case resizing. Are you saying that you just NK resize, and "never" bump the shoulder back? If so, you must be forcing the bolt closed on your handloads.

- Innovative

 

[DougW]

No, you don't have to bump the shoulder on the .303 as the case is fire formed to the chamber and the shoulder will not move enough to need bumping. The only way to really bump the shoulder is to full length resize, and I don't want to work the brass that much. The bolt closes easily on the loads, as long as they are used in the rifle they were formed for. I have other rifles that will not chamber my reloads, as the chamber and headspace are tighter. Never had a problem chambering my loads in my shooter.



Look close and you can see that the necks are resized enough to hold the bullet. Remember, this is a military weapon with a purposly loose chamber to handle mud, dirt, and twigs, something a current day precision rifle or benchrest rifle will never see. The case shoulder grows from "factory new" standards to the actual chamber on the Enfields. I have never seen one that doesn't.

 

[Innovative]

DougW ......

Sooner or later, you'll notice tight fitting rounds. Bumping the shoulder or FL resizing will help. Good luck.

- Innovative

 

[yakimaman]

My headspace issue

I just picked up a really decent looking #4 and took it to the range last weekend. I had some surplus ammo dated 1981 of South African manufacture. When it went off at all ( some took two or three attempts before firing) most cases show damage that I assume is due to headspace issues. No complete separation but some were cracked all the way around as shown in pictures in a number of sites. The cocking piece also blew halfway back to full cock a number of times. So, head space, worn or weak firing pin, or ????

rm

 

[madcratebuilder]

My first guess is excessive head space. SA ammo is the best and should go bang every time unless it's been wet. Have a smith check it out. What number bolt head do you have? Do the bolt numbers match the receiver?

 

[yakimaman]

It's a #1 bolt head - receiver #, the # on the "ring" and the #'s on the bolt handle all match. I scoured every source I can find for bolt heads - can't believe that with the millions of #4 rifles in existence, that bolt heads are that scarce. Must be gold.