Lee-Enfield No.4 RARE Bolt Head size 4

[lngstrt]

A couple years ago, Alan de Enfield did a survey of bolt head sizes over on gunboards .........

No4 Bolt Head Survey and Instructions

I remember draggin out all my #4's and parts and measuring!!

Information

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[Peter Laidler]

Thanks for putting that up again ingstrt. The chart part was featured on this site too. It illustrates exactly the point that while the bolt heads are numbered - just like Bren and L1A1 locking shoulders and barrel nuts etc etc, they should be a guide and not treated as gospel as even when they were new, the ACTUAL lengths all seemed to be pretty fluid regardless of the supposed size and merge into each others..........

[Roger Payne]

Yes, I'm sure if you measured a hundred of each size & took the average, then it would show an incremental increase as you go from 0 to 1 to 2 to 3, but there is so much variability within sizes you can't assume anything...

[Ridolpho]

So then, is it safe to assume that newly issued rifles fresh from the factory might have 0, 1 or 2 bolt heads depending on what was necessary for proper fitting after the proofing of combined barrel, action and bolt? The rather large small and large "tails" in the size distributions in Alan de enfields data seem rather surprising- is there something about the machining procedure for these bolt heads that rendered the ultimate size somewhat unpredictable?

Ridolpho

[Brian Dick]

I've seen a couple of the nos '55 date Fazakerley rifles with #3 bolt heads fitted. They are the exception but DO exist. I was surprised to say the least.

[Peter Laidler]

Clearly the short answer is yes Ridolpho! Machining tolerances and a degree of wear being the culprits

Had a chat about this No4 size conundrum this afternoon and the most Southern Command/District senior REME civilian small-arms examiner has confessed that he's never seen a No4 size either - or even heard of one. To be honest, he doesn't believe they exist either. But I'll leave out exactly what he said about Roger and Brians eyesight!!!! Unknown to me there was an actual gauge to 'size' bolt heads at Field and Base workshops that didn't depend on the size marked on the bolt head.

It was kept in the oily gauge box on his bench and consisted of a 1" round collar EXACTLY 1" deep and calibrated annually (until about 1995 he thinks). The centre is bored through to the diameter of the threaded bolt head tenon. Get the picture so far? The gauge is placed on the surface plate and a cleaned off bolt head is slipped into the hole and comes to rest. A dial test indicator pre set to 1" is lifted and swung over the cartridge surface of the bolt head. The length of the bolt head is THAT distance MINUS 1".

You could simply use the gauge and bolthead with a 1-2" micrometer or vernier if you were so inclined but that's something else I learned. And he still doesn't believe in a No4 bolt head exists.

Annanuvver fing too...... The 00 bolthead was supposedly only fitted at the factory to L39's. NOT SO! Donnington Base Wksp were also equipped with these when necessary to re-barrel L39's too.

[Brian Dick]

Tell the examiner he's absolutely correct about my eyesight but I DO have a brand new set of glasses!! Cost me a friggin' fortune too. I'm going to ask out friend Badger to post some pics. I swear he's going to fire me one of these days!!

[Robert303]

I've just read the useful article in the link at #21. Can I ask what is CHS? I suspect I my not be he only one jat does not know and needs to learn.

[Roger Payne]

The rifle is still filthy dirty with old grease - just as it came to me in 1997! I would agree with Peter's mate about my eyesight as I've worn specs since I was 10, but here are some photo's for what they're worth......

[Peter Laidler]

Believe me Roger and Brian, I wouldn't have believed it either unless it was you that told me. Both M and F....... But no BSA. Presumably. BSA, being a private sub-contractor would never have been allowed a relaxation for shoddy production as to warrant a non standard oversize bolt head to cure 'wanting' standards!

We ain't seen a Savage or LB either!

As for what is CHS Robert (thread 28) It stands for Cartridge Head Space. I'll let the experts chime in now as I've only got 2 hrs to spare..........................