Headspace guages and safety

[bunkysdad]

I can't help but wonder how many out there have put off the purchase of a headspace gauge for whatever reason. After several years of buying, and my 10th Mosin on the way, I thought that I had better get serious about checking my headspace. I have 6 Mosins I think, and 2 Enfields that have not been fired awaiting a pass with a field gauge. Some will not fire a gun that fails a no-go check, but I am happy if it passes a field gauge check. The Okie Headspace Guage is a true bargain. If you do not have one, why not? I admit I was lucky and the headspace is good on the Mosins I have already fired. Now I need to check the rest, and I am planning to post some pictures of the simple process.
if you have doubts about headspace checking, or don't know what it is this is the placed to ask. Simply put, the headspace guage is placed flat on the head of the bolt, and if the bolt will not close completely, you are good. If the bolt will close then the space is too large between the bolt face and chamber. That can cause a dangerous condition.

[lonewolf]

i have not done that to any of mine guns yet and i have shot them all and they shoot good.

[dou44]

i went alon time before i got one for the mosin nagants, i only had a couple for a while that i had checked but when i started buying so many i did not know which one had been checked.i bought the field from okie and it is the easiest one i have ever used.just widh they had it in 8mm because i would retire the one i have now.the price is not that much for not having to wounder about it.

[lonewolf]

why do you need to check the Headspace for? have one for an enfield 303 but i never uesed it

[WeldonHunter]

why do you need to check the Headspace for? have one for an enfield 303 but i never uesed it

Correct headspace helps insure the cartridge is completely chambered and sealing when you fire the rifle. If not excess chamber pressure could cause cartridge failure as well as serious injury to the shooter. Like the rifle blowing up, worse case senerio. Mosin Nagant rifles don't have chamber vents to vent excess pressure in case of cartridge failure like some rifles do.

[BuckeyeSgt]

I bought one. I'm with dou I wish they made an 8mm. I like my ugly face the way it is. And I like having all my fingers.

[zeebill]

i have not done that to any of mine guns yet and i have shot them all and they shoot good.

And you may only need one not to do it to and fail and have a bolt lodged in your brain for the rest of your now very short life. I gambled that on head space when I first started with shooting many years ago and got lucky too! I like to think I am much wiser and older now and would never do it anymore. Spend the money and buy a field gauge like the man said. They don't cost that much and could save your life and injury to others around you and the resulting suits against your survivors. Bill

[pacanis]

ooh, a headspace thread

I have done a LOT of reading on headspace and a lot of talking with a gunsmith. Here's my summary on what I have found, including half of the opinions of other shooters out there in internetland.

I find it really odd that besides some early Enfields and Springfields that had heat treat issues, an actual documented case of a bolt shearing the lugs upon firing and then flying into the cheekbone of shooter has yet to be produced. It makes for good internet reading though when someone mentions it. In my honest opinion it seems more like an urban legend at this point. I don't want to say I would love to see a documented case of this happening, but yeah, some proof would be nice.
And these old bolt action rifles were tested at much higher pressures than your typical modern commercially loaded cartridge produces. And thrust into the hands of soldiers and taken into battle. FWIW.

Do I have headspace gauges? Yes. I have no-go gauges for 7.62 x 54r, 7mm Mauser and 8mm Mauser.

I have a 93 Oviedo Spanish Mauser that failed the no-go gauge. I took it down to the LGS and he fired off a new Remington round through it while holding a string with the rifle strapped to a tire. The case showed no visible signs of stretching nor did it measurably stretch any. In his opinion this is a safe test. It is also a test used by half of the shooters I've read their opinions on this matter. One shooter even took it as far as to wrap white paper around the receiver to see if excess gasses leaked. And they did. And the bolt stayed put. And didn't Dou44 here have a shell rupture issue where gasses leaked into his face? The headspace was fine if I remember correctly. No bolt shearing lugs and imbedding into the shooters face either. Just a cartridge failing and the rifle doing what it was designed and built to do.

I was told by my gunsmith there are two options you can use if your rifle has headspace issues, just to error on the side of caution. One is to fire brass once. He told me that he has never heard of a modern ammunition stretching to the point of separation. Modern ammunition being the key words here. He made no claims on surplus ammo.
The other thing he mentioned was for the reloaders. He said that if you reload you can just resize the neck. That way the body of the shell will have stretched to take up any extra space. That is, if it stretches to begin with.

So, to summarize; Should you check headspace? Yes. And use caution when firing a round the first time (fail or pass) and check the fired casing well afterwards for signs of stretching and fatigue. But bad headspace does not equal a rifle that shouldn't be fired. IMO and half of other shooters'opinions.

[WeldonHunter]

This rifle didn't necessarily blow up because of a headspace issue but the poster isn't sure. I know one thing any extra steps you can take to help prevent a failure is a good thing. Whether or not it's ever been documented that a Mosin has blown up I wouldn't want to be the one eveyone posts about it happening too.

http://www.thetruthaboutguns.com/2011/0 ... t-blew-up/

[zeebill]

ooh, a headspace thread

I have done a LOT of reading on headspace and a lot of talking with a gunsmith. Here's my summary on what I have found, including half of the opinions of other shooters out there in internetland.

I find it really odd that besides some early Enfields and Springfields that had heat treat issues, an actual documented case of a bolt shearing the lugs upon firing and then flying into the cheekbone of shooter has yet to be produced. It makes for good internet reading though when someone mentions it. In my honest opinion it seems more like an urban legend at this point. I don't want to say I would love to see a documented case of this happening, but yeah, some proof would be nice.
And these old bolt action rifles were tested at much higher pressures than your typical modern commercially loaded cartridge produces. And thrust into the hands of soldiers and taken into battle. FWIW.

Do I have headspace gauges? Yes. I have no-go gauges for 7.62 x 54r, 7mm Mauser and 8mm Mauser.

I have a 93 Oviedo Spanish Mauser that failed the no-go gauge. I took it down to the LGS and he fired off a new Remington round through it while holding a string with the rifle strapped to a tire. The case showed no visible signs of stretching nor did it measurably stretch any. In his opinion this is a safe test. It is also a test used by half of the shooters I've read their opinions on this matter. One shooter even took it as far as to wrap white paper around the receiver to see if excess gasses leaked. And they did. And the bolt stayed put. And didn't Dou44 here have a shell rupture issue where gasses leaked into his face? The headspace was fine if I remember correctly. No bolt shearing lugs and imbedding into the shooters face either. Just a cartridge failing and the rifle doing what it was designed and built to do.

I was told by my gunsmith there are two options you can use if your rifle has headspace issues, just to error on the side of caution. One is to fire brass once. He told me that he has never heard of a modern ammunition stretching to the point of separation. Modern ammunition being the key words here. He made no claims on surplus ammo.
The other thing he mentioned was for the reloaders. He said that if you reload you can just resize the neck. That way the body of the shell will have stretched to take up any extra space. That is, if it stretches to begin with.

So, to summarize; Should you check headspace? Yes. And use caution when firing a round the first time (fail or pass) and check the fired casing well afterwards for signs of stretching and fatigue. But bad headspace does not equal a rifle that shouldn't be fired. IMO and half of other shooters'opinions.

The former owner of the surplus outfit in NJ was killed by a bolt that blew out backwards into his brain and killed him. Out of an Enfield I was told. This was recounted to me by an employee during one of my visits there. That alone is enough "Urban Legend?" for me to believe!

Rimmed cartridges. like the Mosin, lessen the head space issue by just the way the head space is measured true but I still want to be sure. As recounted a Mosin does not have any reliefs for a pierced cartridge so it either spits out the bolt or relieves itself through the many bolt pieces. Having a multi piece bolt helps us in that small way at least.

I don't use any modern cartridges and only shoot older and full power military cartridges. Why because they are cheaper in true bulk and available to me and I shoot only military weapons.

You need to read more about the early 03's and heat treating issues. After reading a small volume from many different sources online and in books I really think the real issue was with the available ammo during the War and shortly after it. The quality and consistency of the ammo was really lacking and I and many others feel the same way. Indeed I do shoot an early suspect 03 (although from a year that never had a failure) and the previous owner shot it also for many years. Again this is taking a chance in my eyes and I try and shoot reduced load commercial ammo when I can find it but otherwise use surplus.


Living in the country I have a few tree rifles as we call them out here. This being because you find a big tree and put the rifle on the other side of the tree from you and fire it the first few times. Checking the brass for splits, failures, stretches, and wrinkles. If they are there the rifles gone from my hands and usually given to a local gunsmith for parts or sold for a giveaway price to him. He is told why and I know him well enough that I know he will not sell it to the public. Matter of fact he has a war time K98 that he thinks was purposely sabotaged by slave labor he keeps for display only.

I will try and find the really good article about 03's and heat treating if I can get the old computer web browser to work and you can decide about the heat treating for your self. There is so much contradicting information out there on the 03 I can't fault you for saying they were bad but this one article brings up many unassailable facts and figures I choose the other way of thinking from it and many other things I read.

Keep in mind we all think differently about life and that is one thing that makes us really good at forming opinions so some one thinking unlike you is not the end of the world. Bill

[tjtM38]

I don't own headspace gauges for the 7.62x54r/Mosin Nagants. I own six of these guns, all Russian arsenal refurbs with matching bolt and receiver numbers. I have safely fired hundreds of rounds through four of them and have at least test fired or fired multiple rounds through the other two. There have been no indications of any headspace problems with a variety of surplus ammo and my own handloads.

Isn't it true that these guns were refurbished, refinished, headspace checked and test fired at the refurb facility? If so, I can't see the point in investing in expensive headspace gauges for a 100 dollar gun that is a arsenal refurb matching (even electo-pencil matching) receiver number and bolt.

[WeldonHunter]

Is this it Bill? http://m1903.com/03rcvrfail/

[WeldonHunter]

I don't own headspace gauges for the 7.62x54r/Mosin Nagants. I own six of these guns, all Russian arsenal refurbs with matching bolt and receiver numbers. I have safely fired hundreds of rounds through four of them and have at least test fired or fired multiple rounds through the other two. There have been no indications of any headspace problems with a variety of surplus ammo and my own handloads.

Isn't it true that these guns were refurbished, refinished, headspace checked and test fired at the refurb facility? If so, I can't see the point in investing in expensive headspace gauges for a 100 dollar gun that is a arsenal refurb matching (even electo-pencil matching) receiver number and bolt.

$26 isn't expensive in my book. I guess it all boils down to how daring you are. Remember everytime you shoot any firearm you're basically taking your life in your hands, trusting that the ammo wasn't over/under loaded and the gun is in good mechanical shape.

Edit:
One thing I'll add is remember we have inexperienced shooters coming here for advice and can get mixed messages. My reccomendation is to err on the side of caution and do what ever you have to for saftey's sake. Remember that just because someone has the title of gunsmith sometimes they can get lax about saftey and as we've seen recently with the user than has the problem with his rifle not chamberuing rounds was told by a gunsmith it was fixed. I'm a Master Certified auto technician and was a shop foreman and will be the first to tell you I don't know it all. I also have seen parts changers that have the same certifications as me that I wouldn't trust to fix a hotwheel.

[pacanis]

Zeebill, you said I need to read more about 03's... and I say you need to read my post more slowly.
I specifically stated that it WAS documented in early Enfields and early Springfields. No argument or differing opinion there.

And I would certainly not treat headspace issues lightly, just not as significant an issue as what some (half) make out. Kind of like walking across the road to your mailbox. You just never know.

[WeldonHunter]

Zeebill, you said I need to read more about 03's... and I say you need to read my post more slowly.
I specifically stated that it WAS documented in early Enfields and early Springfields. No argument or differing opinion there.

And I would certainly not treat headspace issues lightly, just not as significant an issue as what some (half) make out. Kind of like walking across the road to your mailbox. You just never know.

As long as you're walking across the road with your eyes closed and earplugs in it's like shooting a firearm. That's the only way it would be similar. Either way then you'd never see it coming.

[Hobe Sound Falcon]

What is the best one to get, and where to get it?

[WeldonHunter]

What is the best one to get, and where to get it?

http://www.okiegauges.com/

He's a member here and a sight sponsor. His banner ad is at the top of the page. He sells three gauges but if you only want to check for safety I believe the field gauge will work. If you plan on getting the no go and field I'd just get all three. It's only $3 dollars more for the set as aposed to the two guages at $26 a piece. Make sure you let him know you're from the forum.

GO: measures the minimum acceptable headspace. This size is most often used when re-barreling or re-chambering a firearm.

NO-GO: This gauge is used to check for excessive headspace. If a firearm closes on the NO-GO gauge it is an indication that the weapon MAY not be safe to fire. Reloading ammunition for a firearm that fails NO-GO can result in unsafe loads due in part to the expended brass being elongated as a result of not being firmly chambered. Most military surplus firearms that pass NO-GO (the bolt will not fully close on the gauge) are considered safe to fire with surplus ammunition, or with modern loads not intended for reloading.

FIELD: A firearm failing the NO-GO spec can be tested on the slightly more forgiving FIELD gauge. Military chamber specifications are generally looser than commercial firearms, giving them a bit of tolerance for adverse conditions such as dirty chambers, weather extremes, etc. A firearm passing FIELD spec (not closing fully on the gauge) is generally considered safe to fire the ammunition it was designed to fire, i.e. military surplus ammunition of the designated caliber.

These are to be considered GENERAL GUIDELINES and are in no way intended to be an assurance of the safety of a particular firearm. If you have doubts about a firearm’s safety and usability you should have it checked by a professional gunsmith.

[Junk Yard Dog]

You have it so easy today, when I started collecting milsurps we didn't know what a headspace gauge was or were to get one if we did. We were told by the old timers to just strap that smoke pole to an old truck tire, tie a string to the trigger, hide behind a tree and fire it with a pull on the string. After that if the fired case looked normal we were good to go. It's a wonder any of us fools made it past our teens for a variety of reasons, but the blind faith we put in rusty relics would certainly rank high on the list. These days I do have gauges, I have them for 8mm Mauser and Lebel, .30-06, and .7.62x51mm ( no way I would fire an Indian 7,62mm Enfield without a check first) .303 Brit, and of course 7.62x51mm. Enfields that fail a headspace check even with a field gauge are common, swap a bolt head around until you find one that makes it pass same as the Mosin. Someone once tried to explain to me why Enfields so often seem to have shit headspace, something about The British imperial measurement system, and gauge specs that differ from the modern SAMMI specs we use today. Probably bullshit as I have many Enfields that passed just fine with a US made No/Go gauge. I have a lot of refurbs, and Mosins in General, I never had a Finn Mosin fail headspace, not even the Soviet captures, but Antique M91's from the Balkans watch out, some of them can have frighteningly bad headspace. Soviet refurbs, think they are good to go? Wrong, they are not, out of the 60+ refurbs I own a handful failed headspace, some spectacularly, and failed so even with the field gauge. In every case the problem was solved with bolt head swaps before firing, something I was able to do because I knew ahead of time that there was a problem. Rumor used to have it that the refurbs were checked by the importers, yea, right. Turk Mauser's, I would not fire one of them without checking it first even if you offered me a couple of grand, unless I could fire it from behind a tree with a string on the trigger that is. Almost none of them have matching bolts and they saw a steady diet of hot Turk ammo all of their service lives. One of the very few rifles I have not been able to correct bad headspace on with bolt body swaps is a K Kale Turk Mauser. There is no gauge that would measure the headspace in that rifle, it simply has no headspace, I can't complain as it was sold to me as a parts rifle because of this, and is soon to be a wallhanger once I finish cleaning it up.
At least four of my Turk Mauser's had headspace issues so bad that I had to swap bolt body's around, this involved buying extra bolt body's and utilizing the ones I already owned, but the problems were fixed so they pass the No/Go. As I get older I find risk taking is less to my liking and whatever I can do to minimize risk, especially to my person, I will do, headspace gauges are just not that big an expense even when I have to buy rimmless ones from Brownells as Okie only makes gauges for rimmed cartridges like the Mosin, Enfield, and Lebel use.

[Rongo]

why do you need to check the Headspace for? have one for an enfield 303 but i never uesed it

Correct headspace helps insure the cartridge is completely chambered and sealing when you fire the rifle. If not excess chamber pressure could cause cartridge failure as well as serious injury to the shooter. Like the rifle blowing up, worse case senerio. Mosin Nagant rifles don't have chamber vents to vent excess pressure in case of cartridge failure like some rifles do.

Great advice WeldonHunter... I like my face where it is thank you.

[polymerase2]

People drove cars for years without seatbelts. You will never see me without a seatbelt. Why risk your face, life or eyes at all when you can test the headspace for $30. I have the Enfield no-go and a Mosin no-go. They are part of the initial cleaning process.