No. 4 Enfield chambers

[screwcutter]

Some brass pic from No. 4 I* & II and No. 1 chambers.
158827158828

1. 303 from .405 Win
2. HXP 303
fired in No.4 MKII
3. R-P 303
fired in No.1 barrel
4. 303 from .405 win
5. WW II WRA 303
6. WW 303 setioned to check for seperation
7. WW 303 from sectioned batch
8. R-P 303 Same batch as 9
9. R-P 303 seperated
fired in No.4 MKI*
10. R-P 303
11. R-P 303
fired in No.1 barrel
Neck sizing helps for sure as do my boolit loads.

[screwcutter]

Another one, some are the same.
158856
These were fired in No.4 MKI* except the 2 on the far right, that were fired in No.1
barrel.
2 Winchester made World War II WRA cases, 2 30-40 Krag converted to 303,
2 Sellier & Bellot, an FN 50 Berdan primed, WW 303 setioned to check for seperation next to WW 303
from Same batch.

[303Guy]

Those chambers have a nice shoulder, not blowing the shoulder forward.

For me head separation is a non issue - doesn't happen ever, even when loading to near max. My test cases got many reloadings with no failures. Neck splits on the other hand ....

[roots911]

I know that when I had my Savage Enfield the only resemblance between the fired cases and the unfired ones was the headstamp. I did the rubber O ring trick on the first firing and neck sized after that. Had good accuracy and case life. Was shooting cast 316299 sized to .315. Fun mil surp to shoot.

[leebuilder]

Good thread thanks for sharing. I have much the same results with my 303's. I have seen a few with the war time chambers that blow the neck as much as a 0.100" forward. I get spit necks from over working the brass and substandard brass. Blown the base off a few from the same causes. If you load a lot of 303 you need a ruptured case extractor. I have rechambered many 303's to get better results and accuracy. Headspace is not as common as elongated chambers. Seen a few with flaws in the chambers could be from Bubba's or other acts of neglect or lack of patience.
Be safe

[longbow]

Mine seem to have long chambers too and fired brass has a significantly shorter neck than new or factory (or full length resized) brass. I neck size only with a Lee collet die and 0.313" mandrel because even neck sizing overworks brass when dies squish the neck to suit nominal 0.312" bullets and I am using 0.315" boolits.

Occasionally I have to push the shoulder back a little as I have one No. 4 with tighter chamber than my No. 5's. They chamber but are tight and all my brass was used in the No. 5's first.

Annealing and neck sizing gives good brass life.

Longbow

[Der Gebirgsjager]

I'd like to learn something from this thread, as I have several No.1 Mk III* rifles, several No. 4 Mk. 1 rifles, a couple of No.4 Mk. 1/2 rifles (no Mk.2s) and one No.5. The No.1 Mk. III* rifles were, to me, the big offenders on cracked/separated case heads, and the most difficult of the lot on which to correct the headspace without rebarrelling. I can't say that I recall having experienced the cracked/separated case heads on the No. 4 rifles, and correcting the headspace on them by putting on a size larger bolt head is much easier. Recently, I believe it was Ballistics In Scotland, it was stated that some of these problems were less due to bad headspace than the cartridge brass manufactured in the U.S.A. as having a smaller than spec case diameter just forward of the rim. What I do know is that I have some headspaced so well that when a new round is fired there is no visible ring forward of the rim, but most do show at least a faint or more noticible ring as in the photos, and that neck sizing and annealing is the answer to longer life. So what I'm wondering, screwcutter, since you seem to be a man of few words and a believer that a picture is worth a thousand words, what are you trying to show here? I wish you'd start left to right and comment on each case so I could understand it a bit better.
Thanks.
DG

[rondog]

I like my Enfields, but don't enjoy shooting them much because of the obese chambers and sewer pipe barrels. I wish I could rebarrel them all.

[screwcutter]

DG
I added an edit with a few words to Original Posts
I just wanted to get out pictures of the base expansion.
Everyone seems to be stuck on the headspace and shoulders blown forward I haven"t seen
pictures of large base cases.

[Der Gebirgsjager]

Many thanks for the clarification and additional information on your photos. The cracked cases fired in a No.1 barrel certainly coincides with my experiences. It is interesting that the case you sectioned doesn't really appear to have thinning. The .303 from .401 brass seems to have held up well as did the Greek case. I've found R-P and W-W to have the shortest life. Interesting.

[Frank46]

The greek HXP and the serbian ppu or nny cases are probably the best for reloading. I have shot rp and win 303 and as was pointed out the section above the rim exhibited some really horrible bulges. So much so that they went into the great scrap bucket. Frank

[bigbore52]

Thanks for starting this thread Screwcutter - got me to do some tinkering on my #3 chambers...... unlike other posters, I've not had any separation issues at all with a variety of brass - but others I know can't even get passed one before they let go.... neck splits; well, that's just normal I reckon with usage, so maybe I'm just lucky....

The other day with some spare time I chamber cast one of my #3's - a 1908 which has seen very little use and in what you would call mint condition - was quite surprised at the results.

I found that generally the specs of the chamber came in at what SAAMI list or near enough to it but the big difference was on chamber length - the #3 was cut exactly 20 thou deeper than the specs showed and again, those specs weren't listed specifically for a #3 or 4 etc, just for what I would assume was a generic SMLE chamber..... I'm not aware of what the original specs should be - perhaps others here know and could post?

If it is the norm on the SMLE (??) then my thinking would be that is going to place an awful lot of pressure on a case itself given it's bottleneck shape and head spacing from the rim to the shoulder - the only direction it can move is forward (assuming proper bolt facing etc) probably why some brass fails more than others - equally why annealing helps to some degree as with neck sizing.......from conversations with other SMLE users, we all seem to share the belief and accept that some rifles chew through the brass more than others irrespective of their condition, we know certain brass gives best use for reloading and additionally we steer clear of particular brands of brass as alluded to here by previous posters...so maybe it gets back to what ingredients they use in that brass and how their cases are constructed as to their suitability for the SMLE chamber....after all, doubt whether reloading for the SMLE was a prime consideration when they were designed ....that shouldn't deter people reloading for it .....just my two bobs worth at least........good shooting all the same.

[PAT303]

I like my Enfields, but don't enjoy shooting them much because of the obese chambers and sewer pipe barrels. I wish I could rebarrel them all.
Maybe you would enjoy shooting LE rifles if you bought decent quality ones instead of worn out junk?.If you own a generous chambered LE just set the barrel back one thread and re-cut the chamber using a field reamer instead of a military one and your good to go,getting it done cost less than 100 rounds of ammo. Pat

[screwcutter]

WW brass fired in P14, no bulge.
159226

[Multigunner]

During wartime No.4 production improper pre-fitting of the barrel shoulder resulted in massive over torqueing to get the barrel to clock in. This cause microscopic stress lines to form in the chamber area. On proof firing many of these chambers elongated and/or bulged slightly in the chamber shoulder area.
Later a "breeching washer" was introduced to make barrel fitting easier and more precise.