Enfield headspace issue?

[NC_Xplorer]

Hello everyone,
I shot my No.4 in a CMP vintage rifle match on Saturday and I was using new reloads that I had worked up using new brass. I experienced multiple cases with visible splits about .125 to .250 above the rim and at least 3 complete head separations. My Enfield is fitted with a #3 bolt head. From my research on this forum I have concluded that I have excessive headspace issues. Will this require a gunsmith to fix or is there another solution? I know from reading a copy of a manual that was posted here that I have the largest bolt head already. I don't think switching to a lower numbered bolt head will fix this. Has anyone else had a similar problem like this?

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[Bindi2]

Hello everyone,
I shot my No.4 in a CMP vintage rifle match on Saturday and I was using new reloads that I had worked up using new brass. I experienced multiple cases with visible splits about .125 to .250 above the rim and at least 3 complete head separations. My Enfield is fitted with a #3 bolt head. From my research on this forum I have concluded that I have excessive headspace issues. Will this require a gunsmith to fix or is there another solution? I know from reading a copy of a manual that was posted here that I have the largest bolt head already. I don't think switching to a lower numbered bolt head will fix this. Has anyone else had a similar problem like this?

This is not a headspace problem. Your cases are too small for your chamber. The case is lying in the bottom of your chamber held firm by the bolt on fireing the case expands more to the unsupported side causeing head separation at worst. Solution 1 use a fireforming light load or add a O ring to the case to centre it in the chamber before fireing. Get better fitting cases or better quality ones. Do not mess with the bolt untill you are 100% sure it is not the ammo

[Edward Horton]

To expand on what Bindi2 said above, a chain is only as strong as its weakest link and the weakest link here is shooting American made .303 cartridge cases. Our American made commercial .303 cases are designed to shoot in rifles with smaller diameter chambers that have less head space than military designed rifles.

On top of this American made .303 ammunition must be safe to shoot in oldest Enfield's still being shot today. The chamber pressure of the original British .303 smokeless cartridge was 17 tsi or 17 tons per square inch which was later upgraded to 18 tsi and then 19 tsi. These pressures convert to 38,080 CUP, 40,320 CUP and 42,560 CUP respectively. http://www.gordonengland.co.uk/conversion/pressure.htm

The bottom line here is that Lawyers working for the American firearms industry help design the .303 British cartridge case and the factory chamber pressures are kept below 43,000 CUP. The standard rated pressure for the .303 British is 46,000 CUP (copper crusher method) or 49,000 PSI (transducer method).

Below are two fired .303 cartridge cases, on the left is a Prvi Partizan case and on the right is a Greek HXP case. The Serbian made Prvi Partizan case on the left has a larger base diameter than the Greek military HXP case which shows how much the case expanded to meet the chamber walls.



The only cases I buy today are the Prvi Partizan cases because they are made to a higher standard than American made cases and are .010 thicker in the base web area.



Below is a once fired factory Winchester case fired in my 1943 Maltby with the head space set at just under .067, this case has stretched and thinned .009 (nine thousandths) in the base web area.



The second time these cases were reloaded and fired.



Your Enfield "might" have a head space problem, it might also have a large diameter chamber and last but not least it might be suffering from weak wimpy made American SAAMI cases. When it comes to the .303 British I do not believe in the fault finding terms of “inherent weak design”, “rear locking lugs” or any of the other garbage you hear about the Enfield Rifle. I have been reloading a Winchester 30-30 with rear locking lugs for over 30 years and NEVER had a single case head separation.

The only difference between my 30-30 and the British Enfield is the chamber pressure the cases were designed to withstand when fired.



Check your Enfield's head space as a starting point and test fire Remington factory loaded ammunition as a base line test for case head separations. Remington made cases are the thickest of our American made cases and are loaded to lower chamber pressures than reloaded ammunition can be.