Enfield bolt head

[gew98]

Stumbled on this thread...if it helps anyone wiht their enfield bolt head problems.

http://forums.gunboards.com/showthread.php?194819-Enfield-Bolt-Head-Conversion

[Multigunner]

The longest bolt heads for the SMLE were the armorers stash of unissued boltheads that had never been fitted to a previous rifle. These have a very tiny s marked on them. Just having the s intact doesn't always garantee that its still in unaltered condition.
Bolt heads that overclocked in one bolt could clock in perfectly in another, so "part worn" boltheads were kept and recycled when possible.

There was a Canadian dealer advertising the .22 rimfire bolt heads several years ago, apparently original old stock. I have no interest in these so I didn't save the link.

Brian Dick Ltd may be able to help. He seems to be able to find just about any part you might need, and has mentioned obtaining unissued armorers packs of bolt heads before.


My personal opinion is that if you can't correct headspace issues with a unaltered bolthead or a replacement bolt body, setting the barrel back one thread and freshening the chamber is the way to go. Brazing shims and the like is an accident waiting to happen.

[gew98]

"is an accident waiting to happen" , so is shooting a Class C steel '03.
I guess you never followed Frank DeHaas and his classic works on building and modifying single shot rifles of all manner of calibers. He did stellar work in th every regards you impugne.

[Multigunner]

"is an accident waiting to happen" , so is shooting a Class C steel '03.
I guess you never followed Frank DeHaas and his classic works on building and modifying single shot rifles of all manner of calibers. He did stellar work in th every regards you impugne.

Are you saying that welding, brazing, or soldering a casehardened cast maleable iron bolthead is a wise idea, and do you intend to present a notarized document in which you agree to pay all damages should such a modified bolthead fail?

There are factory made boltheads for the .22 conversions, and a few new old stock boltheads and other components for the rimfire comversions.

If the action already has headspace issues that can't be reticified with available bolt heads or a replacement bolt body then the action has already suffered setback of the locking recesses.

Setting a barrel back by one thread and freshening the chamber has been a common method for resolving headspace issues, so long as the action itself hasn't been compromised, since before high powered cartridges first came into common use.

Occasionally you'll find a Enfield with a visible gap where the breech of the barrel should butt against the internal wall of the receiver ring. In such cases its better to set the barrel back than mess with either bolt head or bolt body.

Welding up the firing pin hole of a falling block .32 rimfire to drill it out for use with centerfire cartridges is no big deal, or the opposite to adapt to rimfire .22 ,but screwing around with rifles that operate at much higher pressure levels is a different animal.

Would you buy a Mauser whose manufacturer brazed discs to the bolt face to adjust headspace?

PS
With the reactivated DP rifles floating around and the tendency for some shooters to find a way to break any thing they get their hands on by ignoring every warning and procedure in the manuals and regulations its no wonder accidents continue to happen.
Most Low Number Springfield receiver failures were due to just that sort of lackadasical disregard. Sad Sacks trying to shoot the Cosmoline out of a barrel or a stuck patch etc, or trying to fire German 7.92X57 cartridges, which blew out a few M1917 rifles as well, and other such antics.

Pierced primers are usually due to defective ammo or chipped firing pin tips. I've replaced the firing pin of a 95 Mauser because some one several decades earlier had warped the pin by a clumsey disassembly and over the years the pin tip wore against the side of the pin hole till it took on a half moon cross section.
Dry firing without snapper caps or a once fired primer to cushion the impact can also mess up a firing pin by chipping away part of the tip.

As you may have noticed in the thread you linked to several involved in the discussion also had their concerns about support for the primer if the bolt face were plated.

Do as you like though.

[gew98]

Sammy ; Being the kiwis and aussies have been doing such bolt head conversion & repair for decades nary a kaboom because of such... I dare say they know what they are doing...alot of practical experiance on their end .
Setting the barrel back is common for mauser types to an extent as that is really the ONLY way to rectify headspace issues with an acceptble chamber and or no lug setback. It's just more simple a fix on the enfield to address the bolt head through replacement or repair when all is said and done. And since you are not a gunsmith and it's quate apparent not well familiar with the enfield I cannot put much stock in your suggestions.
Oh and there have been plenty of mauser conversions of th ebolt..like those shotguns made from gew98 actions between the wars...and they made oodles of them , and they are oddly enough quite safe.
Do you have documentation to back up your claim of "grunt ignorance" being the biggie in popping 03's like grenades ?. I don't think you do as even in Brophy's book that was quoted as a supposition...with no factual basis.

[Multigunner]

Sammy ; Being the kiwis and aussies have been doing such bolt head conversion & repair for decades nary a kaboom because of such...
That you know of.


Do you have documentation to back up your claim of "grunt ignorance" being the biggie in popping 03's like grenades ?. I don't think you do as even in Brophy's book that was quoted as a supposition...with no factual basis.

Check Hatcher's Note Book, and his own investigation into numerous such incidents. There are many listed as unknown causes and others due to known defective ammunition, but of the failures with known causes a number were due to knuckleheads that believed they knew better than the manuals and instructors.

Examine your purchases a bit better in the future, maybe you won't end up a statistic.

Since no one here seemed to have the foggiest idea in the metallurgy of the Boltheads till I posted the information I'd found, and the old time Australian gunsmiths at least knew that much, their work would likely hold up well enough. I wouldn't be so sure about how well the work of those like yourself might hold up since you seem determined to just make things up as you go, and have admitted your own tendency to abuse your firearms.
Be my guest though, at worst you may become an object lesson.

Now enough with the vain attempts to rile me, you are bringing down the quality of the forum with your attitude.

Perhaps you should ask the admins to give you your own private Springfield Bashing forum, then you can carrying on to your hearts content rather than just trolling the Enfield threads.

PS
To repeat the information I found earlier

The SMLE specs called for No.34F Special Gun Iron, a very pure malleable "white" cast iron with an extremely high resistance to compression. This metal also has an unusual ability to old lubricants like a bearing, which reduced thread wear.
These were casehardened.

I don't know if other metals or alloys were used for the No.4 but I suspect simple cast steel may have been used as well. Drop forged might be better though.

Edited to add
The Specs for the SMLE boltheads made from 1938 onwards were
"Head, breech bolt -- Steel B.S.S.5005/103 -- Case hardened and polished"

So its likely this steel was used for the contemporay No.4 boltheads.



The M marked boltheads are Cast Iron, the M stands for "Mild Steel" but White Cast Iron is listed as mild steel in British metallurgy hand books.

While resistant to compression the cast heads have less shear strength than steels.

Threads for the SMLE Boltheads are diameter .4175 X 20 TPI
The No.4 dia .4375 X 20 TPI


The "Steel B.S.S.5005/103 " may be weldable, though I wouldn't reccomend rewelding any bolthead.
The specification are in a obsolete British standard.
The fellow who found this information had posted a link to a book on British Metallurgy nomenclature, but it went dead.

The Lthgow Boltheads may not conform to the same specifications.

I'm not sure why any gunsmith with access to the mountains of surplus bolt heads and bolt bodies that were once available would bother rebuiling a bolthead.
I have seen a tutorial on something similar, but had figured it was an experiment.

Conventional wisedom among UK shooters has always been that tight headspace was of no importance, that it was an groundless obsession of American shooters and reloaders.

I have rifles with excellent or above average close headgap so I have no reason to cobble together bolt heads.
New condition BSA replacement bolt bodies are also available every now and then. They aren't that hard to fit, but if you doubt your skill level hire a pro to do the work. Brian Dick Ltd may be able to help.

[gew98]

So fran DeHaas , australian and Kiwi smithy's are complete idiots in your thinking and your engineer like pontification of 'metalurgy facts' from cutting and pasting somehow trumps their practical working knowledge which as it so happens has and does work. I know such fellows have an intimate grasp of what they are doing , that you disagree , oh well.
I have more than one source for 1903's being dangerous of the Class C steel variety and it was not largley a soldier issue..as noted a combination of lousy ammunition & tough environment(s) pretty much exposed the weaknesses of those rifles , hence so many having been scrapped when brough t in for repair/rebuild.