303 head space
- Thread starter jessie01
- Start date
Headspace is best checked with headspace gauges.
Some folks feel that a cartridge case with shims between the boltface and the cartridge can give a good indication.
What do you mean by "expanding at the base"?
Case life in Lee Enfields can be enhanced by neck or partial sizing. Complete full length resizing can contribute to reduced case life.
Some folks feel that a cartridge case with shims between the boltface and the cartridge can give a good indication.
What do you mean by "expanding at the base"?
Case life in Lee Enfields can be enhanced by neck or partial sizing. Complete full length resizing can contribute to reduced case life.
monkeycanada
Regular
Take it to a good gunsmith, headspace guages are expensive (about $100) and hopefully they would not charge you that. If you have a Lee Enfield the headspace and easily be changed by changing the bolt head for the next size up (I believe there are four bolt head sizes).
- Location
- Grande Prairie, Alberta
do what those guys said. but i'll tell you how i did it.
go to gravel pit, crown land. load gun. put on a work glove. hold gun with gloved hand around behind a tree, so that the tree is between you and the gun. fire gun. eject spent casing. then examine casing for stress or damage. if the casing is marked or damaged, probably you have too little head space. if gases etc come out of the action, and other nasty stuff happens, you may have too much headspace.
yes i know, it's a pretty idiotic way to do it. i was told this method by a very experienced shooter, and being the cheap prick i am, figured i could save the 60 bucks an hour the gunsmith charges. lucky for me, my gun had no problems.
go to gravel pit, crown land. load gun. put on a work glove. hold gun with gloved hand around behind a tree, so that the tree is between you and the gun. fire gun. eject spent casing. then examine casing for stress or damage. if the casing is marked or damaged, probably you have too little head space. if gases etc come out of the action, and other nasty stuff happens, you may have too much headspace.
yes i know, it's a pretty idiotic way to do it. i was told this method by a very experienced shooter, and being the cheap prick i am, figured i could save the 60 bucks an hour the gunsmith charges. lucky for me, my gun had no problems.
A simpler improvised test is to take a primed case and fire it. Have a look at how much the primer protrudes from the pocket. You could measure the primer protrusion, add that to the rim thickness, and this would tell you the distance between the breechface and the boltface. If it is over .074" you might look for a longer bolthead.
I wouldn't count on work gloves to provide much protecton in the event of a major failure. Then again, I have never seen any harm done by a case separation in a Lee Enfield, apart from the inconvenience of the front portion of the case having to be removed from the chamber. If I need to test fire something that I would not hand hold, I sandbag the sucker in place and use a string.
Lee Enfields frequently have generous headspace. Case separations are not all that uncommon, especially when cases are reloaded. Loading so that headspace is controlled by the shoulder, rather than the rim can reduce problems. In the past, I have acquired cases fired in gov't property rifles. I could count on culling at least 20% because of incipient separations - and these were new cartridges fired in issue rifles.
I wouldn't count on work gloves to provide much protecton in the event of a major failure. Then again, I have never seen any harm done by a case separation in a Lee Enfield, apart from the inconvenience of the front portion of the case having to be removed from the chamber. If I need to test fire something that I would not hand hold, I sandbag the sucker in place and use a string.
Lee Enfields frequently have generous headspace. Case separations are not all that uncommon, especially when cases are reloaded. Loading so that headspace is controlled by the shoulder, rather than the rim can reduce problems. In the past, I have acquired cases fired in gov't property rifles. I could count on culling at least 20% because of incipient separations - and these were new cartridges fired in issue rifles.
easy headspace check. put a piece of tape on case head, insert bolt should just close, repeat with second layer of tape, bolt should not close. if it does use next size bolt head, and repeat.
Now the brits weren't too worried about reloading, so they made most chambers large enough to work with the grime/mud of battlefield operations, not nuch to do except maybe have a smith turn the barrel back a turn and recut a tighter chamber. good luck
Now the brits weren't too worried about reloading, so they made most chambers large enough to work with the grime/mud of battlefield operations, not nuch to do except maybe have a smith turn the barrel back a turn and recut a tighter chamber. good luck
"...Headspace is best checked with headspace gauges..." Headspace is only checked with guages. Bits of tape the cartridge or anything else will tell you nothing. The cartridge will give you indications that the headspace may be bad though.
"...guages are expensive..." Kind of. $25US each from Brownell's. However, you don't need the whole set. A No-Go and a Field will do. If the bolt closes on the No-Go, try the Field. If it closes on it, the headspace is excessive and the rifle is not safe to shoot.
The ease and expense of fixing it depends on which model you have. A No. 4 Rifle's bolt heads are numbered. 0 to 3, only. You can try the next number up with the guages, if the one you have is a 0, 1 or 2, but that alone does not guarantee a fix. You may need one that is two numbers up. If you have a 3, you can try changing the bolt body for a longer one. Otherwise, it's an expensive smithing job.
If you have a No. 1 Mk III, the bolt heads are not numbered. The only way to fix headspace on a No. 1 is to have a handful of bolt heads(at $11.90US each from Gunparts, if they have any) to try with guages until you find one that works.
After all that, you may not have a headspace issue at all. Is the bolt hard to open after firing? Are you seeing primers being severely flattened? Primers backing out? Case head separations? These being the indicators.
When you resize, are you full length resizing? You may not have the die set up properly. Have the headspace checked or buy the guages and do it yourself first then look at the dies.
"...guages are expensive..." Kind of. $25US each from Brownell's. However, you don't need the whole set. A No-Go and a Field will do. If the bolt closes on the No-Go, try the Field. If it closes on it, the headspace is excessive and the rifle is not safe to shoot.
The ease and expense of fixing it depends on which model you have. A No. 4 Rifle's bolt heads are numbered. 0 to 3, only. You can try the next number up with the guages, if the one you have is a 0, 1 or 2, but that alone does not guarantee a fix. You may need one that is two numbers up. If you have a 3, you can try changing the bolt body for a longer one. Otherwise, it's an expensive smithing job.
If you have a No. 1 Mk III, the bolt heads are not numbered. The only way to fix headspace on a No. 1 is to have a handful of bolt heads(at $11.90US each from Gunparts, if they have any) to try with guages until you find one that works.
After all that, you may not have a headspace issue at all. Is the bolt hard to open after firing? Are you seeing primers being severely flattened? Primers backing out? Case head separations? These being the indicators.
When you resize, are you full length resizing? You may not have the die set up properly. Have the headspace checked or buy the guages and do it yourself first then look at the dies.
Headspacing is not a firearm manufacturing term only. It is a firearm manufacturing term derived from real world circumstance. Headspace, as used by manufacturers, is the difference between a measurement from a point in the chamber to the face of the breech compared to the nominal minimum dimension. Headspace, as it applies in the real world is the "space" between the "head" (which could as sensibly be called the base or butt but the term "buttspace" never caught on) of the cartridge and the breech face.
So; in one case you have the headspace measurement as it is in theory and in the other, as it is in practice. Placing layers of Scotch tape on the head of the case (tape= about .0015 per layer) is a viable way to establish what the headspace is with a given piece of brass. Doing the same thing with a "go" gauge will establish what the headspace is in relation to the nominal minimum.
Either way, it is better to remove the striker to better feel contact as the bolt is closed. On a Lee Enfield, the angled locking lugs and seats, in combination with the stretchiness of the action, will allow considerable compression of the tape so one must have a feel for it.
Brass which is bulged at the base has nothing to do with headspace. It is instead a result of the difference in diameter between the chamber and the unfired cartridge. On a military rifle this can be considerable. Regards, Bill.
So; in one case you have the headspace measurement as it is in theory and in the other, as it is in practice. Placing layers of Scotch tape on the head of the case (tape= about .0015 per layer) is a viable way to establish what the headspace is with a given piece of brass. Doing the same thing with a "go" gauge will establish what the headspace is in relation to the nominal minimum.
Either way, it is better to remove the striker to better feel contact as the bolt is closed. On a Lee Enfield, the angled locking lugs and seats, in combination with the stretchiness of the action, will allow considerable compression of the tape so one must have a feel for it.
Brass which is bulged at the base has nothing to do with headspace. It is instead a result of the difference in diameter between the chamber and the unfired cartridge. On a military rifle this can be considerable. Regards, Bill.
Sunray,
You may have noticed I commented on the necessity to feel the contact of the bolt on the tape; especially when working with a Lee Enfield. This due to the design of the Lee Enfield and the compressability of the tape (Scotch tape is actually not real compressible). The method remains a workable means of checking the headspace of a rifle. In other words, bits of tape may tell you nothing but they can tell me plenty! If the use of tape seems too crude for you, steel shim stock may be substituted. Tape is a bit more convenient though. Regards, Bill.
You may have noticed I commented on the necessity to feel the contact of the bolt on the tape; especially when working with a Lee Enfield. This due to the design of the Lee Enfield and the compressability of the tape (Scotch tape is actually not real compressible). The method remains a workable means of checking the headspace of a rifle. In other words, bits of tape may tell you nothing but they can tell me plenty! If the use of tape seems too crude for you, steel shim stock may be substituted. Tape is a bit more convenient though. Regards, Bill.
