Krag Headspace

[StrawHat]

I just received a sporterized Krag. The bolt nearly drops fully into battery on a "Field" Gauge. Using the custom search function, I have found a couple of options.

I guess I can correct this with a new barrel or possibly a different bolt. Or maybe an easier way would be to neck size once fired brass to headspace off the shoulder of the round.

Any other options?

[madsenshooter]

You're not far from Camp Perry and the CMP's custom shop. New carbine length barrels are less than $200, I don't know what they charge for installation. I'd first see how it did with a new bolt body, if the barrel is usable.

[13Echo]

Nearly is not the same as completely. I suspect your rifle is safe but it would be nice to have a bit tighter headspace. Considering the generous chambers in these rifles you should neck size anyway and using the shoulder for headspace is not a bad idea. Otherwise case life is short.

Jerry Liles

[jimb16]

I live in Madison. What community do you live in?

[madsenshooter]

If you was talking to me, a little town in SE Ohio known as Murray City. It's a hard dying old coal town that is now in the middle of several thousand acres of either state or federal woodland.

[leadman]

I would fireform some brass first with a fast powder like Unique and then fill the rest of the case with Cream of Wheat cereal or similar, plug the mouth with wax and shoot them. Then do not set the shoulder back and load some and see what happens.
I have an Encore in 7mm Rem mag that is about .004" to long in the chamber but I fireform as written and I have no problems even with full power jacketed loads.

[Multigunner]

" The bolt nearly drops fully into battery on a "Field" Gauge."

Well if it doesn't close completely on a field gauge its still within safe limits.

You might stay on the look out for older Krag brass which often had rims thicker than the case drawings would indicate as beyond the factory specs.
I have an old Krag cartridge in my collection that has a .063 rim, thicker than the nominal .060 listed in the Krag rules for management but still under the max of .065.
An old gun magazine I have has a survey of .30-40 krag case dimensions from various manufacturers and some rims went as high as .068.
Back when thick rim Krag cases were commonplace many owners of .303 British rifles prefered to trim and fire form Krag cases with thick rims to compensate for generous head space of the Lee Enfields.

You might want to check on whether the safety lug bears when locked. Some Krag owners had their bolts lapped in until the safety lugs came to bear to provide a more solid lock up at the expense of increased headspace.
Also if the action suffered any setback the lug might come to bear. Some had full bearing safety lugs from the factory, but that was uncommon.

So long as fired cases don't show a bright ring or an internal ring once fired cases neck sized only should last quite awhile.
You might do best to obtain fresh cases in bulk and use a medium pressure load for first firing.

[StrawHat]

Thank you all, keep the ideas coming!

[Mark Daiute]

and plenty of new old stock bolt bodies on ebay if that might make a difference.

[Stoats]

"Back when thick rim Krag cases were commonplace many owners of .303 British rifles prefered to trim and fire form Krag cases with thick rims to compensate for generous head space of the Lee Enfields."

As a Brit, can I please repeat that US ".303 Brit" headspace gauges are in fact Krag gauges, and are thus Too Short. And wrong. An Enfield has correct headspace if it does not close on a .074" gauge, end of story.

You don't hear British shooters belly aching about 303 headspace, by the way...

[Multigunner]

As a Brit, can I please repeat that US ".303 Brit" headspace gauges are in fact Krag gauges, and are thus Too Short. And wrong.

The British military changed the acceptable max head space early on. Commercial sporting rifle Headspace for the .303 was .068, military max specs were at first .072 later changed to .074.
As automatic weapons became more common place the case head and case wall dimensions of .303 Ball ammunition were adjusted to avoid blown out case heads and case separations in the Vickers and Lewis guns that had begun to show excessive wear. The case bodies were also partially annealed above the case head so cases would stretch rather than separate.
This cartridge case development allowed for an increase in the acceptable maximum headspace for rifles.
Generous headspace, along with a long chamber shoulder was pretty much a necessity due to the lack of quality control of much of the wartime .303 ammunition.

The .074 headspace field gauge represented the maximum allowable before the rifle would be sent in for a replacement bolt head or bolt body or both if necessary.
When the bolt head or bolt body were replaced they only checked for clearance on a .064 gauge and whether it would still close on a .074 gauge.
The instructions for manufacture of the SMLE in the 30's

Regarding barrel proof, refer to page 12:
(g) Proof. - The barrel will be submitted with the action attached for proof. The distance from end of bolt to face of barrel will be tested with a cartridge head gauge .067-inch. The proof will then be carried out with a proof cartridge, the charge being about 33 grains of No.3 cordite, having a service bullet of 215 grains, giving a mean pressure not below 24 tons per square inch, after which the action will be examined; and the barrel, body, and bolt head will be marked with the proof mark."

I have two sets of commercial Chamber drawings, both state that maximum headspace should be no more than .071.

My Enfields have headspace of .068 and give very good caselife.
Generous headspace is of little or no concern unless you handload, and this board is one dedicated to hand loading.
When headspace and resulting head gap are at or near the maximum acceptable for a worn rifle there are ways to compensate.
If you don't wish to handload for a Enfield don't worry about it so long as you don't get case separations when firing factory ammo. If you do get separations then find a source for milspec .303 ammo suited for use in automatic weapons.

IIRC the maximum headspace for .303 rifles in Australia is tighter than the SAAMI maximum headspace. Those figures are for recently manufactured rifles and not necessarily for century old warhorses.

If a rifle left the factory with headspace of .073 then it would likely exceed the milspec max of .074 before the rifle was properly broken in.

[Multigunner]

PS to the above.
According to every source I've found on the subject few British Enfield owners handload. For more than a century cheap (relatively speaking) .303 milsurp ammunition was supplied to the NRA UK for sale to target shooters.
Whenever a case of a blown out bolt head in the UK or commonwealth has been mentioned the first suspect is always handloaded ammo. Dismissing the fact that headspace is important to handloaders has led to this sort of accident.

[Shiloh]

and plenty of new old stock bolt bodies on ebay if that might make a difference.

That is a viable option. I had mine checked before firing. Within spec, actually pretty good. I neck size and anneal when they get hard and springy.

Shiloh

[Der Gebirgsjager]

I acquired my first US Krag in 1969 and over the years acquired many more in various configurations. My experience has been that most of them were out of heaspace specs, and I suspect that if fired enough eventually all of them will be out of headspace. The problem is (1) the single locking lug, and (2) the 19th Century metallurgy. Both adequate for their time, but most of these rifles were fired thousands and thousands of rounds, some had their barrels changed more than once, and many were subjected to the stress of hunter's handloads. This results in wear to the lug and wear to the inside of the receiver where the lug locks. Not much you can do about the second, but in the case of the first you can scour e-bay and the gun auction sites and sooner or later you may run across a gentleman named Stu Barlow who seems to have an inexhaustible supply of unissued, still in the grease, brand new bolt bodies. He gets about $90.00 apiece for them. I bought several and found that by putting them into the mix and swapping bolt bodies around I was able to put all of my rifles back into "won't close on the no-go gauge" condition. In the case of collector condition rifles it doesn't really matter because the part isn't serialized. This sure beats the time and cost of a barrel job, and believe it or not if your rifle is too far out of specs a barrel job may not be able to solve the problem. On the subject of Lee Enfields and their headspacing, here's an interesting story. My first No.1 Mk III* was out of specs so badly that I could only get about 2 or 3 reloads from a piece of new brass before the head separated. At the time, early 1970s, Springfield Sporters advertised that they had the largest inventory of L.E. parts in the world, so I phoned them and explained the problem to a nice lady who said that they had oversized bolt heads that would solve the problem and would sell me one. When it arrived I noticed that it was black in color rather than blue, and that it had an "eX" stamped on it. Sure enough, it put the rifle back into headspace. So a few years later I again had the problem with a different rifle, again phoned Springfield Sporters, again talked to the same lady who no informed me that they had been sued in court by some collectors who said that oversized Mk III bolt heads did not exist, and had lost the case, and because of that there were none; but in any event, what I had previously purchased was sold out. Next thought I had was to swap bolt bodies around, and since (back then!) they sold unissued specimens for $6 each I ordered 10 of them. No two things are truly alike, and by swapping them around I have been able to restore all but one Mk III to proper headspace. This is a bit more complicated than bolt body swapping with Krags, because you have to factor in the separate bolt head which screws on, and often the timing of the threads isn't correct to bring the bolt head to where it needs to be. When in gunsmithing school, I was working on one of these rifles and an instructor loaned me his 2 lb. coffee can full of bolt heads. Only two would work properly with the existing bolt body, but neither would solve the problem, which was eventually corrected by swapping out the bolt body. The underlying principle here is that no two things are truly alike. A few years ago I was looking over the website of a famous pistolsmith and noted that he listed Krag rifles as one of his personal interests. So I sent him an e-mail and asked what his experience was with the headspace problem. He said that his solution was to just dedicate small lots of brass to a particular rifle and just neck size only after firing. He said that his current interest had shifted to No.4 Lee Enfields, and did I just happen to have a size 3 bolt head? I did have one still in the grease from back "in the day" when I purchased parts generously, and I sent it to him for having taken up his time. About a week later I received a mystery package that turned out to be an autographed copy of his $70.00 book on custom pistols. Nice surprise.

[Multigunner]

again phoned Springfield Sporters, again talked to the same lady who no informed me that they had been sued in court by some collectors who said that oversized Mk III bolt heads did not exist, and had lost the case, and because of that there were none;

The SMLE boltheads were all oversized before the first time they were fitted to a rifle before the action was proofed.
Unissued SMLE boltheads have a tiny s stamped on the extractor lug.
When the bolt was first fitted to a SMLE barreled action body if the bolt wouldn't close on the go gauge they glued a piece of fine sand paper to a precisely made flat steel plate and hand ground the bolt head face till the bolt would close.

Later on if a rifle developed excessive headspace they would first search through buckets full of used bolt heads to find one that both clocked in properly and would close on the go gauge but not on the field gauge.
If none of the used boltheads worked they would break out a new s stamped replacement.
Whenever a new bolthead was used there was some paperwork involved and a justification for the expense.

Since bolt heads aren't serial numbered theres no way of being sure if any SMLE still bears its original bolthead.
When and armorer fitted a replacement bolt body he serial numbered it to the action body.
The only way to be sure if a bolt body is original is if both action body and bolt body have the PAA (Proofed Action Assembly) numbers on butt socket and under the bolt handle root.
If the numbers are not present thats common enough even if the bolt body is original.

[Der Gebirgsjager]

That is really great information, Multigunner, and dovetails in well with what my experience has been in working with these fine old rifles. A great bit of history--thank you! That also explains why I have a couple of rifles equipped with bolt heads that have strike throughs on the bolt head number and a second number added. Now if we could just locate a supply of those unused Mk III bolt heads.......probably at least as rare as the size 3 head for the No.4 or more so.