....
- Thread starter The Hackmaster
- Start date
- Location
- land of f-cktards
full length resize ?
calling Andy !
calling Andy !
saskgunowner101
CGN Ultra frequent flyer
- Location
- near Prince Albert
I will guess a headspacing issue. I don't know enough about Enfields except you can swap bolts on some of them to get a tighter fit.
blaser.306
CGN Regular
- Location
- Saskatoon , Sask
.303 loads
Looks like quite possibly headspacing issue . In the future try using once fired brass "out of that chamber" and neck size only and compare results !
Looks like quite possibly headspacing issue . In the future try using once fired brass "out of that chamber" and neck size only and compare results !
blaser.306
CGN Regular
- Location
- Saskatoon , Sask
.303 loads
I just remembered another trick that I heard of ,try to find some 30/40 krag brass and run it thru your full length sizing die . If I remember correctly the krag brass has a thicker web and the bases are also a little thicker , helping to cure some headspace issues !!!
I just remembered another trick that I heard of ,try to find some 30/40 krag brass and run it thru your full length sizing die . If I remember correctly the krag brass has a thicker web and the bases are also a little thicker , helping to cure some headspace issues !!!
43 grains, isn't that a bit too hot? Or at least it is with the IMR 4320 I load behind 174 grains. Max load for these is like 39 grains for 2400 fps.
I've loaded over that, maybe 42 grains and got separated cases like yours sometimes. Especially with cases loaded more than a few times. But I have a Nitro proofed barrel, so I don't scare easily.
RL-15 max load is 40 grains for 2400 fps in my bible.
Add to that the poor headspacing factor, a tight crimp and the results are mighty close to dangerous. And how close are you to the rifling with your bullets.
I've loaded over that, maybe 42 grains and got separated cases like yours sometimes. Especially with cases loaded more than a few times. But I have a Nitro proofed barrel, so I don't scare easily.
RL-15 max load is 40 grains for 2400 fps in my bible.
Add to that the poor headspacing factor, a tight crimp and the results are mighty close to dangerous. And how close are you to the rifling with your bullets.
Last edited:
I don't see any signs of excessive pressure. Primers look fine.
There should be an expansion ring about 1/4" up from the base. That is where the solid head is making the transition to the casewall, and where the case expands.
Incipient, partial and complete separations in the expansion ring area are not uncommon with Lee Enfield rifles. Can result from reloading a case which has been fired in a rifle with excess headspace and then reloaded. It is not unusual for there to be incipient separations on first firing in an issue rifle.
What happens is that the firing pin drives the case foreward. Primer fires, pressure spikes, case expands and is held to the chamber wall, base of case is forced back against the boltface, the case stretches in the web area. If it stretches too much, there will be a separation.
Check the headspace of your rifle. Correct if necessary. Carefully inspect new factory cases fired for the first time. Any sign of incipient separations? Cull any cases which show signs of separation. You can examine the inside of the case with a little L shaped probe, or with a good light. If you are suspicious, section a few caseheads. Size the necks of good cases only enough to hold the bullet.
Even if headspace is minimum, and cases are not overstretched, separations will still occur after cases have been reloaded repeatedly.
The Lee Enfield action flexes every time it is fired, and this is harder on brass than if fired in other actions.
There should be an expansion ring about 1/4" up from the base. That is where the solid head is making the transition to the casewall, and where the case expands.
Incipient, partial and complete separations in the expansion ring area are not uncommon with Lee Enfield rifles. Can result from reloading a case which has been fired in a rifle with excess headspace and then reloaded. It is not unusual for there to be incipient separations on first firing in an issue rifle.
What happens is that the firing pin drives the case foreward. Primer fires, pressure spikes, case expands and is held to the chamber wall, base of case is forced back against the boltface, the case stretches in the web area. If it stretches too much, there will be a separation.
Check the headspace of your rifle. Correct if necessary. Carefully inspect new factory cases fired for the first time. Any sign of incipient separations? Cull any cases which show signs of separation. You can examine the inside of the case with a little L shaped probe, or with a good light. If you are suspicious, section a few caseheads. Size the necks of good cases only enough to hold the bullet.
Even if headspace is minimum, and cases are not overstretched, separations will still occur after cases have been reloaded repeatedly.
The Lee Enfield action flexes every time it is fired, and this is harder on brass than if fired in other actions.
tiriaq, maybe you can answer another question at the same time here. I have a mix master Savage No4 MKI* that was doing the same thing as Hack Master's rifle.
I agree that pressure doesn't seem to be the issue here nor was it with mine. I checked the head space with a field go/no go gauge and all was well. A friend suggested that some of the so called "flex" in No4 actually comes from the rear locking lugs not being square. I thought it was worth a try, so I lapped in the rear lugs. It took quite a while, and the end result was I had to go from a #1 bolt head to a #2 bolt head. The field gauge fit was tight but not excessively. The rifle was noticeably more accurate (still not a tack driver) and the case head separation was no longer a problem. There was still a lot of expansion because of the oversize chamber but that isn't abnormal or a problem as far as I'm concerned.
This was a relatively easy fix as I had the parts, it may not be for some one looking for the parts or not having the gauges.
The question is, is this a normal fix for No4 rifles that for some reason has been overlooked or is this a one time oddity? In some of the accurizing manuals I've read, I've never seen mention of lapping the lugs. It's common practice on target and custom rifles, why not on the No4?
I agree that pressure doesn't seem to be the issue here nor was it with mine. I checked the head space with a field go/no go gauge and all was well. A friend suggested that some of the so called "flex" in No4 actually comes from the rear locking lugs not being square. I thought it was worth a try, so I lapped in the rear lugs. It took quite a while, and the end result was I had to go from a #1 bolt head to a #2 bolt head. The field gauge fit was tight but not excessively. The rifle was noticeably more accurate (still not a tack driver) and the case head separation was no longer a problem. There was still a lot of expansion because of the oversize chamber but that isn't abnormal or a problem as far as I'm concerned.
This was a relatively easy fix as I had the parts, it may not be for some one looking for the parts or not having the gauges.
The question is, is this a normal fix for No4 rifles that for some reason has been overlooked or is this a one time oddity? In some of the accurizing manuals I've read, I've never seen mention of lapping the lugs. It's common practice on target and custom rifles, why not on the No4?
I do know that British gunsmiths who accurized SMLE rifles for competition did lap the lugs. I have heard that some lapped the lugs differentially, to try to control the flex and vibration. Don't have any specifics about this. All Lee Enfield actions flex when fired. If only one lug is making good contact, the flex is going to be increased, and a greater lateral component to the whipping introduced. Sounds as if you made a real improvement in your rifle. It is not unusual for there to be uneven lug contact if there is more than one lug, in any action. Multilug actions may be the worst offenders, particularly if there is no final fitting in manufacture. I've heard that proof testing increased the number of lugs making contct in the Rem. 788. I have observed uneven or partial lug contact in Rem. 700s.
- Location
- Georgetown Ontario
Look at a fired round and compare it to a new round. Notice the difference! "Hint shoulder area" 303 rounds stretch a lot when fired, so try neck sizing only when reloading and you wont get the brass flow from the web causing the bulge and possible case head separation issues. Reloading for my No.1Mk.3 when I full length sized my cases they looked as yours and I had one separation on the first time reloads! Bought a neck sizer and now I have cases going on 5 reloads with no signs of separation.
303 reloading
Is that a bad thing to do?.
As long as the case rim is not being pushed back & not properly contacting the chamber.
Not being funny, I just want to learn all I can before actually reloading 303.
Peter (Burlington, Ontario)
Is that a bad thing to do?.
As long as the case rim is not being pushed back & not properly contacting the chamber.
Not being funny, I just want to learn all I can before actually reloading 303.
Peter (Burlington, Ontario)
centerline
New member
- Location
- New Brunswick
As several others have pointed out, it looks like you need a different bolt head to reduce the clearly excessive head space. Your removable bolt head has a number on it (0,1,2,3,4 or 5) The higher the number, the greater the reduction in headspace. Get a new, unfired, preferably unprimed, empty case. Obviously, don't use a live cartridge!! Try higher-number bolt heads until the bolt won't close. Use the next-lower number bolthead (ie the highest number which will still comfortably close). Where to get these other bolt heads? Try to borrow from friends until you know what size you need, then buy your own. Expect higher numbered bolt heads to cost more than lower numbered ones, because many persons need them. As to the brass you have already fired: they are now ruined trash & should not be reused.
Civilian brass sometimes (should I say most of the time) have very thin rims. This may cause a heaspace problem with a large chamber.
I measured Remchester brass rims as small as 0.054", while mill brass usually runs around 0.062" (0.058" to 0.064").
Try the "protruding primer method" to give you an idea of the headspace of your rifle. Always us spent primer, though.
This text comes from the "Textbook of Small Arms, 1929, War Office" pp 194/195;
Test No.4 for Cartridge Head Space
1. With Rimmed Cases. - This type of case is positioned in the chamber by its rim butting on the face of the breech, and in order to ensure easy closing of the breech the space between the face of the bolt (or its equivalent), when fully forward, and the face of the breech must not be less than the greatest thickens of rim likely to be encountered in any cartridge.
This space, known as cartridge head space, must, however, be limited, since if it is greater than the thickness of the rim, the case will be forced back onto the bolt face on firing, and that portion of it immediately in front of the rim will be thereby removed from the support of the walls of the chamber. If the extent of this unsupported portion is excessive the case may burst.
With the British Service cartridge, as issued, no case with a thickness of rim more than .064 inch, or less than .058 inch, is likely to be found, these being the high and low limits of the manufacturing tolerances. Gauges with rims .064 inch in thickness form the lower limit when testing cartridge head space. Actions which close freely over this gauge will take all service cartridges. The amount of tolerance beyond this depends on several factors, and experiments have proved that the setback or case movement should not exceed .02 inch, otherwise separations may occur.The maximum amount of cartridge head space allowable has been determined as .074 inch, and gauges of this dimension are used by armourers in carrying out this test. Even a cartridge with a rim thickness of .058 inch is then unlikely to receive insufficient support, as the set back is only .074 inch - .058 inch = .016 inch.
I measured Remchester brass rims as small as 0.054", while mill brass usually runs around 0.062" (0.058" to 0.064").
Try the "protruding primer method" to give you an idea of the headspace of your rifle. Always us spent primer, though.
This text comes from the "Textbook of Small Arms, 1929, War Office" pp 194/195;
Test No.4 for Cartridge Head Space
1. With Rimmed Cases. - This type of case is positioned in the chamber by its rim butting on the face of the breech, and in order to ensure easy closing of the breech the space between the face of the bolt (or its equivalent), when fully forward, and the face of the breech must not be less than the greatest thickens of rim likely to be encountered in any cartridge.
This space, known as cartridge head space, must, however, be limited, since if it is greater than the thickness of the rim, the case will be forced back onto the bolt face on firing, and that portion of it immediately in front of the rim will be thereby removed from the support of the walls of the chamber. If the extent of this unsupported portion is excessive the case may burst.
With the British Service cartridge, as issued, no case with a thickness of rim more than .064 inch, or less than .058 inch, is likely to be found, these being the high and low limits of the manufacturing tolerances. Gauges with rims .064 inch in thickness form the lower limit when testing cartridge head space. Actions which close freely over this gauge will take all service cartridges. The amount of tolerance beyond this depends on several factors, and experiments have proved that the setback or case movement should not exceed .02 inch, otherwise separations may occur.The maximum amount of cartridge head space allowable has been determined as .074 inch, and gauges of this dimension are used by armourers in carrying out this test. Even a cartridge with a rim thickness of .058 inch is then unlikely to receive insufficient support, as the set back is only .074 inch - .058 inch = .016 inch.
