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My dad has hunted with the same .303 British sporter for 40 years. When doing some pre-season shooting this year a case seperated cleanly at the bottom. I assume there is too much headspace from wear. Is this a simple or complex repair?
.303 case separated - headspace?
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Jim Watson
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Factory or reload?
Chambers are pretty sloppy even when headspace is correct and brass from full charge reloads does not last long. Bear in mind that for a rimmed cartridge, headspace is based entirely on the rim thickness and action clearance for it. The chamber can be oversize (as many .303s are for easy extraction in the trenches) and still show normal headspace.
The headspace repair is to replace the bolt head. Naturally it has gotten hard to find the longer heads as the guns wear.
Chambers are pretty sloppy even when headspace is correct and brass from full charge reloads does not last long. Bear in mind that for a rimmed cartridge, headspace is based entirely on the rim thickness and action clearance for it. The chamber can be oversize (as many .303s are for easy extraction in the trenches) and still show normal headspace.
The headspace repair is to replace the bolt head. Naturally it has gotten hard to find the longer heads as the guns wear.
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It was a reload S&B case with a middle-of-the-road charge according to Lymans. Case looked to be in excellent condition. He had fired 13 rounds from the same box before that one failed. Are you thining it might just have been a worn case, or is it possible that the chamber itself is worn out of spec?
Jim Watson
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I think it is a worn case. The chamber does not get bigger with use, although the locking lugs or their abutments in the receiver can get beaten back.
The chambers on Lee Enfields were intentionally made sloppy. It improved their reliability under battlefield conditions. Unfortunately, it also causes brass to withstand less reloadings than it otherwise might. It's a pretty common problem.
Stephen A. Camp
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Hello. I believe that the problem is "insipient case separation" due to the (purposely) excessive chambering tolerances for the old SMLE bolt-action war horse. Full-length resizing multiple times restores the brass to original specs each time but these cases were really expanded to fill the "generous" chamber. FL resizing in this instance REALLY "works" the brass. I solved the problem by going with a Redding sizing die that sizes only the neck. The gun runs slickly but understand that neck-sizing will probably limit using neck-sized handloads to but one rifle, the one they were originally fired in before neck-sizing.
Best and good luck.
Best and good luck.
rcmodel
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Case inspection before reloading will easily cull out the bad ones before they separate.
Bend a paper-clip or wire with an L-bend on the end.
Reach down inside each case and feel for a annular ring inside the case at the location the case broke on the one you have.
If you can feel the stretch ring, that case is very near to separating on the next firing or two.
You can also back off the sizing die a little until sized cases will just chamber with slight resistance on bolt closing.
That will cause the case shoulder to headspace the cartridge instead of depending on the rim to do it, and will reduce the amount of stretch each firing / reloading cycle.
rc
Bend a paper-clip or wire with an L-bend on the end.
Reach down inside each case and feel for a annular ring inside the case at the location the case broke on the one you have.
If you can feel the stretch ring, that case is very near to separating on the next firing or two.
You can also back off the sizing die a little until sized cases will just chamber with slight resistance on bolt closing.
That will cause the case shoulder to headspace the cartridge instead of depending on the rim to do it, and will reduce the amount of stretch each firing / reloading cycle.
rc
Fatelvis
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Neck sizing your brass will eliminate that problem. I've loaded the same S&B brass for cast loads 11 times now, without 1 case failure out of 100.
351 WINCHESTER
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I have found S & B brass to be the worst offender when reloading for my .303 British. Too brittle I think. Neck sizing, reducing loads will help your brass to last longer.
<SLV>
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Thanks for the tip on S&B cases. They've served me well in other calibers. I'll pick up a neck sizing die and go that route. Most of this brass was fired in another .303, so I full-sized them, but I do remember puting a lot of pressure on my press to set the shoulders back.
Is this kind of case separation dangerous? He didn't notice anything abnormal when it failed.
Is this kind of case separation dangerous? He didn't notice anything abnormal when it failed.
dogngun
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I used to own several .303 Enfields, used only neck sizing dies for loading, kept cases separate for each rifle, had no problems.
FWIW even the Enfields with what looked to be lousy bores shot pretty well - great rifles.
mark
FWIW even the Enfields with what looked to be lousy bores shot pretty well - great rifles.
mark
303 British, 30/40 Krag and brake over actions have inherent problems when it comes to case life longevity, the 303 British (SMLE) have two locking lugs, in the rear (not forward locking lugs), this means the bolt is a column that can flex when the rifle is fired, so no matter the head space and fit of the case and sizing technique, when the case lock to the chamber, the bolt flexes and stresses the case at the web, but instead of the head of the case moving back when fired the bolt shoves if forward before the chamber releases the case.
Te 30/40 Krag has one locking lug, if lapping lugs to the receiver seating surfaces is important how important is it to have two lugs, up front, two lugs required the single shot manufactures Springfield to hand fit, this was not cost effective, so they decided the 30/40 Krag only needed one.
Brake over actions/receivers are not rigid,
Measure the thickness of the rim, use only the thickesst rims and I measure case head thickness, I have found 303 commercial cases to have a case head thickness of .130, most are .210 +, commercial 30/06 case head as in R-P is .260 thousands thick.
F. Guffey
Te 30/40 Krag has one locking lug, if lapping lugs to the receiver seating surfaces is important how important is it to have two lugs, up front, two lugs required the single shot manufactures Springfield to hand fit, this was not cost effective, so they decided the 30/40 Krag only needed one.
Brake over actions/receivers are not rigid,
Measure the thickness of the rim, use only the thickesst rims and I measure case head thickness, I have found 303 commercial cases to have a case head thickness of .130, most are .210 +, commercial 30/06 case head as in R-P is .260 thousands thick.
F. Guffey
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