A question of head space

lupothebutcher

lupothebutcher

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So....I have four .303's
No1 mk3 1917 sporter
No1 mk3 1918 restored full wood
No1 mk3 1941 sporter
No4 mk1 1942 restored full wood
(honestly, I'm sitting in a parking lot waiting for my daughter and don't remember the full details)
My question stems from the No1 mk3 1918 restored full wood, I bought this rifle from a nuter and it looks like a pretty good job, when I took it to the range, it puts out distorted brass; now, I don't reload, so I don't really care as far as that goes but, the brass is clearly being stretched, the base comes out at an angle (maybe a degree or two, enough so that if you stand it up, you can clearly see it lean) and you can see a slight line and bulge, maybe 5mils (if memory serves) up from the base on one side; my thinking was either head space or a worn out chamber (barrel looks to be "good" at least, and the chamber shows no flaws that I can see). I bought a set of "go" "no go" "field" gauges, all four rifles fail "no go", all four pass (just) "field".
The question here is, of course, safety; especially if I let anyone else use it. I'm inclined to say "f it, it fired fine, passed the "field" test and should be safe enough". Any thoughts? I know for the No4's, there are the different bolt heads which I assume are for changing the head space, but I don't recall ever seeing the same for the No1's.
If you guys have to see, I can upload pictures of the casings later.
Thanks for any help.
Lupo
 
do the bolts match i.e.serial numbers on bolt match with s/n's on receiver?
if they don't why not try to change bolts around and try your headspace gauges on them now.
on the 4mk1 the heads are numbered from 0-3.zero being smallest and 3 being longest bolt head.which 1 do you have?
distorted brass honestly I would not shoot it until properly checked out--could be bad chamber or even bolt/receiver warped out of shape or flexing too much when fired.

p.s. don't mix no4's and no's 1mkIII bolts up,they are not the same...
 
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If they fail the no go, then the head space is out. It could be the chamber but hard to tell over the net. #1 rifles can be headspaced using different bolt heads. It is a matter of measuring the heads and finding one that is larger. As far as safety goes, if you are not getting case seperation, then you can probably shoot it till the cows come home. That is a very tough gun.
Perfect is great but less than perfect can still be okay. There are those that disagree with this take but that's my opinion.
 
The bolt does match, but the idea of switching around the heads might be worth looking at, I'll measure them all when I get home. The fact that all four rifles fail the "no go" I think I put down to 1) age, and 2) military rifles being known for having pretty loose tolerances; I don't know a whole lot about head spaces but I do know that the "field" gauge is more tolerent than "no go" and that "field" is considered safe; I don't have the numbers here, but, I know that the "field" gauge is just a split c-hair thicker that "no go" so it can't be that far out.
 
Go is .064; commercial No Go is .068; Field is .074. A lot of rifles would accept the No Go, and still be considered serviceable.
 
Are your gauges SAAMI or military gauges? Different gauges if I remember correctly. I know exactly what you mean without seeing pictures of your brass. I have a dozen rifles here all in 303. All the Lee-Enfields do this to civilian spec brass but do not do it to military brass or PRVI brass. The rim is simply too thin on civi brass and it leaves too much of the case unsupported out the back of the chamber. This causes the distorted look. I don't recall the Rosses doing this though.
 
No numbers on No. 1 bolt heads. Fixing bad headspace requires a handful of bolt heads($22 each from Marstar) the try with the guages until the bolt will not completely close. Operative word is 'completely'. If your bolts don't completely close on the Field guage, you're fine.
Firing it means nothing. A rifle with really excessive headspace will go bang every time. Only a matter of time until the bolt head will break and the bolt ends up in your forehead though.
However, the rifle that bends the case has chamber issues that have nothing to do with headspace. That one I'd retire to a place of honour.
Bits of rubber on the case do exactly nothing for anything.
 
sunray said:
Firing it means nothing. A rifle with really excessive headspace will go bang every time. Only a matter of time until the bolt head will break and the bolt ends up in your forehead though.
However, the rifle that bends the case has chamber issues that have nothing to do with headspace. That one I'd retire to a place of honour.
Bits of rubber on the case do exactly nothing for anything.
Click to expand...

Wow where do you come up with this stuff???

Unless the headspace is WAY out of spec excessive headspace causes nothing more then the case to fireform and stretch in the web area!!

The buldge isn't a problem, the brits reamed out chambers on Smle's to help with chambering out of spec ammo and ammo covered in mud during the great war.


OP, a hair tie or rubber o-ring on the case slid back to the rim will take up any slop in the headspace on a lee enfield. I've been doing it for years but only because I reload so I prefer to have the shoulder pushed forward during the first firing keeping the stretch in the web area to a minimum.
 
It was very, very quiet, but the British started reaming their chambers extra-generously - read QUITE oversize - about the middle of 1916.

Reason for this was to accommodate the rifles to that terribly-oversized ammunition that BM&M was turning out: the same stuff that jammed the Ross. It also jammed the LE, some of it was so bad. This was not mentioned out loud for a reason: they were withdrawing the Ross at that time because it was "no good" but they were smart enough to recognise that they had exactly the SAME problem with their own rifles, for the same reason.

Yes, some of the brass can look pretty weird, but expansion at the front is meaningless with rimmed cases.

Two people have suggested O-rings or pony-tail ties when firing your fresh ammo. TRY IT. Done properly, it reduces your effective headspace to ZERO and your brass comes out fire-formed to THAT rifle perfectly, ready to reload for MATCH accuracy at half the price of new ammo.
 
lupothebutcher said:
So....I have four .303's
No1 mk3 1917 sporter
No1 mk3 1918 restored full wood
No1 mk3 1941 sporter
No4 mk1 1942 restored full wood
(honestly, I'm sitting in a parking lot waiting for my daughter and don't remember the full details)
My question stems from the No1 mk3 1918 restored full wood, I bought this rifle from a nuter and it looks like a pretty good job, when I took it to the range, it puts out distorted brass; now, I don't reload, so I don't really care as far as that goes but, the brass is clearly being stretched, the base comes out at an angle (maybe a degree or two, enough so that if you stand it up, you can clearly see it lean) and you can see a slight line and bulge, maybe 5mils (if memory serves) up from the base on one side; my thinking was either head space or a worn out chamber (barrel looks to be "good" at least, and the chamber shows no flaws that I can see). I bought a set of "go" "no go" "field" gauges, all four rifles fail "no go", all four pass (just) "field".
The question here is, of course, safety; especially if I let anyone else use it. I'm inclined to say "f it, it fired fine, passed the "field" test and should be safe enough". Any thoughts? I know for the No4's, there are the different bolt heads which I assume are for changing the head space, but I don't recall ever seeing the same for the No1's.
If you guys have to see, I can upload pictures of the casings later.
Thanks for any help.
Lupo
Click to expand...

As per Peter Laidler. If the bolt comes within .050" of the wrist with the field gauge (.074) in it is a pass. A no-go was never used in the British military.

http://photos.imageevent.com/badgerdog/generalstorage/peterlaidlerpostsleeenfieldforums/Cartridge%20Headspace%20_CHS_.pdf
 
Loose head space will not destroy the bolt. Ever. Very loose headspace can cause case seperation. Even then you don't usually notice anything wrong till you extract only the back end.
 
Crooked brass is the norm for a Lee Enfield. The spring loaded extractor will push the brass to one side of the chamber while firing, causing it to expand unevenly. Some folks say the o ring helps to centre the brass - cant say one way or the other.
Your rifle is completely normal, sorry to say.
 
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