Home Forums Hunting & Shooting Ask The Gunwriters Gas venting and modern bolt actions

A recent thread about an exploded rifle got me thinking about the safety of two brands of rifles I own when it comes to venting gases in the event of something like a case rupture. I read a very long thread from a few years ago about this topic. A very common opinion was that Mausers are great "venters" that vent the gases away from the shooter's face, but the most knowledgeable seemed to think the safest of all were the "sealers," like the Remington 700 and the Savage 110.

The only centerfire rifles I own are Tikkas and Howas - just kind of worked out that way. I understand that the Howa is a "venter" designed to direct gases down through the magazine well (I might be wrong there). That seems less than ideal? I am curious what your thoughts would be. Also, people criticize the safety of adding a sako-style extractor to a Remington 700, but the Howa bolt has a sako-style extractor. Is that an issue?

I am more curious about how modern bolt actions compete - those from the last twenty years or so. These are mostly cheaper designs, like the Ruger American, Mossberg Patriot, and the Winchester XPR. But also of course I'm wondering about the Tikka. How do these compare in safety to the safest bolt actions, such as the Savage and the Remington?

I wonder how concerned I should be about this topic. I wear safety glasses and do not lose sleep over it. I don't reload. But I now have a child, and someday I will teach him to shoot - I don't like the idea of handing him anything less than the safest action I can find. Is this mostly a non-issue? Are we talking about very remote possibilities here?

You already have one of the strongest, most safe actions in the Howa/ vanguard action. Trade the tikkas for more vanguards and never have to worry again

I took part in an extensive test on blowing up rifles with up to massive over loads ( all over loads the rifles were in a "blow-up" container). The strongest rifle took multiple, I believe it was 6 ea. 220 grain bullets set in the barrel in front of a factory 30-06 load and if held by a shooter, the shooter would not have been harmed shooting that crazy combination. But I have seen pictures that model of rifle with split barrels on the internet.

I am curious about where this thread goes. In my humble opinion, the Remington 700 is the safest. I have one episode to back that up.

I want to hear about the Tikka, Current M70 Winchester, Ruger American for starters.

I believe it when people say that the 700 and Savage are the safest. The trouble is that internet forums have convinced me that I need to own a Tikka to hunt successfully!

Ok Bugger, spill the beans.. what model was the rifle/action that took the beating?

Makes my list of characteristics I care about, but just barely. Vent, seal, whatever, as long as the gas isn’t channelled directly towards my lovely complexion and eyeballs. Had my fun for a few decades with the beloved pre-64 M70, but that one is among the worst at handling gas. The solution is to keep the throttle at a safe level, and always wear eye protection. Actually, that applies to the others too.

Well reading the ongoing thread about the Mossberg Patriot seems to answer some of my questions about the safety of that particular design... Still very curious about the Ruger and Tikka.

I'm happy to hear that the Howa/Vanguard is a strong design, but it seems to me that the Savage and Remington actions are preferable as far as I can understand the differences.

I thought about all this stuff when I was buying my rifles originally. I convinced myself that it was a non-issue, and I heard enough complaints about Savage and Remington to want to avoid them entirely. But I might rather suffer the occasional failure to eject or broken extractor than carry a less safe rifle.

Only 1 personal incident.
Completely separated a 308 in a 660.
First clue was when I opened the bolt and the case was only 1/2" long.


Long story, not bolt actions.
2 760's, 30-06 loaded with 57gr of 4320 (NOT A RECOMMENDED LOAD)

The guy who loaded it used nothing buy 4350 for decades.
Then he bought a 222, and wasn't used to thinking about powder
types, plus the cans are very similar.


Guy shoots the first round.
It kicks, hard!
Smoke comes out the ejection port.

2nd round.
More kick, more smoke.
Action is stuck.
He mortars it open.

3rd round.

Kick, smoke, locked up tight.
Tries to beat it open with a hammer.


Says to his grown son,
"Let's see if they work in you gun?" (Honest truth. And this guy is a skilled mechanic!)

First round.
Kick, smoke, locked up.
Kid refuses to let Dad do anymore stupid stuff.


First gun was basically destroyed.
Between pressure and stupid hammering.

2nd, had the bolt broken.
Nothing else wrong.
Can't buy 760 bolts, gun was parted out.

Barring complete destruction, a Remington pump rifle would be
about as good as it gets.
There is no pathway open between a right handed shooter and the chamber.
At least not to the power plant. The right hand would be vulnerable.

I managed to fire a 270 round in a Savage 110 7 rem mag. Other than a little bit of gas to the face (think a whiff), and some brass shavings in the action and magazine, it was pretty much a non-event. The biggest damage was to my ego.

I shot a 270 in a 7mmRM a couple times. It is worse with hot loads. I will not go to a range bench with those two any more. I will not go to a range bench anymore. I shoot by myself out in the sagebrush now. I can't think while cases from an SKS, AK, or AR are landing on me.

My notes from Oct 2010
I put a 10kpsi 270 round in a 7mmRM, thinking it was a 7mmRM round. I had my warning and promised myself never to do that again.
Then a few days later I loaded a 270 round and grabbed at what I thought was a 270, but was another light weight laminated glass stock rifle, but 7mmRM.
That as a 70kpsi round, and it decided it was time to open up the hinged floor plate.
OK, never mix up 270 ammo with 7mmRM ammo.


In 2010, that glass stock would have been a VZ24 Mauser bolt action that I rebarreled to 7mmRM.

I just found the brass 10 years later. That is what happens when the reloading room is never cleaned.

I blew a primer from a .25-06 in a Winchester Classic action. I had to use a rubber mallet to open the action. I never felt a thing on my face.

I would bet they're not as good.

The Mauser 98 was a frontline rifle, this was cutting edge at its time, they put a lot of resources into its development. These new budget things are just designed to be cheap and easy to manufacture. Gas is not something shooters are concerned with these days. The Tikka I've heard is supposed to quite bad, in theory.

I've got a Turkish model 1903 military Mauser rifle (98 action with bolt shroud etc) in 8x57. I also have some Romanian ex-military ammo of 1970s vintage. The ammo is lacquered steel case and relatively lowish pressure and sometimes the case does not obturate to seal the chamber and gas will come back through the action and I will feel a slight puff on my face when I fire the rifle. My Vergueiro rifle has a tight chamber (and no bolt shroud) and always seals with this ammo. I always wear glasses of course.

I've posted this before, but has anyone had a case or primer let go in a Kimber 84? I always wear glasses, but am one eyed, so I do worry a bit.

I shot a 7X57 in my Remington 700 270. Big ball of fire out of the muzzle, and a stuck bolt. Took a rubber hammer and beat the bolt open, and saw what I'd done. No damage to the rifle, as I shot it a lot after that.

Had been shooting a little above max load in my Remington Model 7 Predator 223, with no issues whatsoever. Tried them in a Weatherby Vanguard (Howa) and got a sticky bolt, and eventually the extractor broke. May have been a faulty extractor from the start, and the hot loads may or may not have had something to do with it breaking. Also, may have had nothing do with that actions ability to handle hot loads.

I’ve been present during two wrong cartridge incidents; one with a pre-64, and the other with a P14 Enfield. In both cases, the floorplates were bent. The M70 extractor was blown loose at the front, but not damaged. The P14 extractor was blown into pieces, one of which hit me, about 15 feet away. The P14 stock around the mag box was shattered. Both shooters’ faces were peppered with bits of brass and powder.

The M70 had been rechambered from .30/06 to some .300 mag, but not marked. The extractor held the case against the bolt face, allowing it to fire.

The P14 was a mystery. It was a British military experimental piece chambered in 7.92 Mauser. The owner suspected that he somehow got a .308 mixed into his ammo, but the case went up in smoke so he wasn’t certain. He’d paid a pretty penny for that rifle, and was able to get it back into action eventually.

That’s disappointing to hear. You’d think that with over a century of bolt action development to build on, it’d be a simple enough thing to engineer a safe bolt action.

Safety? That is not an issue in much of engineering today, think plastic cars. The century of bolt action development has lately been mostly to see how cheap one can build anything.

Actually, I believe cars are safer now than ever before, in spite of plastic and a general feeling of not being as nice. That's why I'm willing to give newer rifle designs the benefit of the doubt. But I'm not an engineer.

I believe so too. Reputable modern cars are designed to crumple and absorb the energy, sacrificial to protect the occupants.

Pierced primers are bad. While not a bolt action, I've been on the firing line next to an M14 that blew out and dissassembled the magazine due to a pierced primer. The bullet left the barrel okay but the gas system didn't eject the case. Funnily enough the magazine spring , follower and floor plate were undamaged and were able to be reassembled seemingly good as new.

I have a customer who shot a full box (20 rounds) of 308 Win in a 270 Win I had built for him. Never popped a primer. He said it grouped well, just kicked really hard and sounded weird. And the bolt closed hard. Point of impact didnt change more than a couple of inches from regular 270 ammo. I guess there really is a god.
Charlie

Charlie and I were fooling with a .308 in the Winchester Classic Action a number of years ago. If I recall correctly, we were trying to see how many firings it took of a stout handload in a single case it took for the primer pocket to open up. Charlie was on the Pressure Trace, and I was doing the shooting. After every shot we'd load the case with the same primer, powder charge and bullet, and shoot.

Everything was going along fine, until about the 12th firing. Again, this is what I recall. May even have it in my loading notes, but it doesn't matter. Everything was normal until that shot--which blew the primer--and a bunch of gas back in my face, along with what felt like brass particles. (I was very glad to be wearing shooting glass, in addition to my everyday glasses.) Couldn't open the bolt by hand; instead Charlie tapped the bolt handle several times until it came loose, probably with a rubber mallet.

We couldn't figure out why it blew. We checked case-length every time we loaded the round, and double checked the powder charge. Might have had something to do with the neck getting brittle, since we didn't anneal the case, but still don't see why everything went from normal to blown with one additional firing.

Anyway, my major point is that the only gas-handling improvement I know between the pre-'64 and Classic Model 70 was a "gas block" added to the left side of the bolt, just behind the left locking lug. Maybe it helped, but I sure got a blast in the face.

My secondary point is that the pre-'64 Model 70 has basically zero gas-deflection or containment. As a somewhat smart-ass gun writer once point out, reliable cartridge cases are what made the pre-'64 possible.

JB, and Charlie, have there been any improvements to the latest M70s from South Carolina and now Portugal in gas handling? Also how about the Tikka and the lowly Ruger American?

I have a CZ 527 in 204 that has pierced 3 primers. Never felt a thing and only noticed the pierced primers upon extraction. I switched from federal 205 GM to 205 AR GM that allegedly have thicker cups and never had the issue again. Not sure if it is an issue with the gun or the primers

Some of the latter NH guns and the current production guns have a small flange on the bolt shroud. I am not sure if this flange or the has block actually do much. In the case of the gas block I would bet its just another piece of shrapnel in the event of a major gas release.

Thanks for posting that, good reminder that pressure signs don't necessarily creep up on you a little nibble at a time.

BWalker,

Yeah, they have a very small "flange," if you can call it that, on the left side of the bolt shroud--but it isn't anything like the bolt shroud on a 98 Mauser. The 70's is not only very small, but there's plenty of space between the shroud and the bridge of the action. In the same place, the 98 shroud extends all the way to the side of the bridge, and fits closely--not in attempt to block gas, but to deflect gas sideways.

I once shot an FN 98 sporter .270 that belonged to someone else, with rather old factory loads. Apparently they had corroded just enough to blow crack in the case, just in front of the head--which happened to be on left-hand side of the case. All I felt was a faint puff of gas on my left cheek.

Did the guy say how this happened? I'm having a hard time comprehending how someone can do this. You have to REALLY not be paying attention to almost anything to do something like this.

I had split case in two instances. On a Ruger 77 in 284 winchester and on a 7X57 Mauser. I felt nothing behind the Mauser, and wind in my face with the Ruger.

I have a hard time believing the box of 308 in a 270 story...

I had a buddy put a .308 round through a 25-06 Remington 700.

Case head was welded to bolt face. We had to open the bolt with a mallet.

Rest of brass was spread across the chamber. But no copper/lead to be found. I know he tried to send it back to Remington. I need to call him and find out what happened to that rifle.

I had two Hornady 9.3x62 cases let go in a Classic Stainless Model 70. The load was 65 grains of Big Game with a 286 grain Nosler. The cases were on their third loading. I was doing some rapid-fire practice and these cases were loaded together. With the first case that let go I noticed it only in retrospect. Thinking about it after the fact I realized there was just a slight puff on my face and no issues with the rifle. Had I been shooting a group it likely would've been enough for me to realize there was an issue to check out. As it was, I was in the midst of rapid-fire and fixated on my next target. The next round caused a rather dramatic gush of air to my face and blew the floorplate open, dumping the remaining two rounds. The rifle was undamaged. Based on this hopefully never again to be experienced issue I'd say the gas handling abilities of the Winchester Classic Model 70 are less than awesome. Thankfully I was wearing safety glasses, as the lenses were etched and the bare part of my face had some stippling.

Lots of investigation later, I determined Hornady brass and RCBS dies are a bad idea for the 9.3x62 loaded to modern pressures. Without going to my notes for all the numerical specifics, there are two problems. First, Hornady makes their 9.3 brass from '06 blanks, likely to decrease costs and ease manufacturing. This is bad because '06 brass is of a smaller diameter ahead of the casehead than 9.3x62 brass is, resulting in a slightly undersized fit in the chamber. This is exacerbated by RCBS dies, which are made to size brass formed from .30-06 brass. This came from long ago, when the 9.3x62 was much less common and RCBS sold forming dies to make 9.3 brass from '06 cases. The brass was undersized to begin with. At first firing it expanded to fit the chamber, then the dies sized them back to '06 size. A couple cycles of this worked these cases beyond what they could bear apparently. Interestingly, prior to this I'd fired a bunch these loads with nary a problem. But it scared the heck out of me! Investigation revealed Norma, Privi, and Lapua cases are properly dimensioned. Lee and Redding dies size cases appropriately. I ended up switching to Lapua brass and a Lee sizing die with the RCBS seater die, which I like better than the Lee seater.

No expert I spoke with had ever seen, or heard of a case failing with a split through the casehead. Has anyone else ever seen this?

They are safe, but they didn't put as much thought, money and time into engineering them nowadays, it's just something for people to shoot a deer, it's no longer being built for the nation's defense. Despite that, probably they are in fact safer with modern metallurgy and cartridges. And the concern today is mostly theoretical, even more since shooters now often wear eye pro. I wonder how some of these budget guns with full diameter bolts will do, since there's no raceways, might be interesting. Most of the gas talk is about older designs, or copies of older designs, because people don't even consider this these days.

Years ago when Dave Gentry was still alive we spent some time talking about this subject at the shop. Hands-down he said the Savage 110 was the strongest, safest action he’d seen. He tested wildcats in them and said he struggled to blow up the action. He didn’t think much of the M70 or M700. Of course he liked the 98, but IIRC thought the Wby action was good too.

The cross sectional area of the bolt lugs in shear stress is almost the same in:
1) 98 Mauser
2) M70 Win.
3) Rem 700
5) Mosin Nagant 91/30
6) sav 110.

I have re barrelled and I have overloaded all (6) actions.
I have killed things with all (6) Actions.

(+) The Sav 110 does have ~~ 5% more bolt lug cross sectional area than the other.
(-) I am done building Sav 110 rifles, but still building the others for my own use.
a) stock availability is poor
b) too many feeding systems
c) too many action lengths
d) too many crazy bolt mods.
e) weak extractors




I did this in 2002 with Turkish Mauser I rebarreled to 243.
I cannot do this in a Sav110, or the extractor falls out.... not even in 223, I tried.

Not relevant but curiosity about the velocities - although not intent, did you chrono any of those Turk loads?

Is anyone currently producing a rifle or just action with the Mauser 98 design?

The older Savage 110's are stronger in shear than the newer ones because the right hand lug is not hollow. GD

Ive looked into this in the past and ive found Mauser makes a magnum 98 action, Granite Mountain Arms has three sizes as does Mayfair Engineering. I believe these are 98 pattern recievers of modern materials and execution. Theres also one by American Rifle Co i think thats the name. Anyway its not a real Mauser per se but a hybrid between a Mauser and 03' Springfield and its called the Mausingfield. That company has some innovative designs and neat looking things. Good news is these small outfits cater even to lefties like myself so we arent left out. Trouble is some of these recievers are north of 4k in cost. Ouch.

This issue of action strength, safety and gas venting has always been on my mind. As a lefty and fan of controlled feed and classic hunting rifles i have tried aquiring such in left jand versions and have several Hawkeyes and a lefty model 70. I know from experiance that the Rugers perform well in frozen crapola and freezing rain type conditions, dust, grit, and muck. They flat work and ive been so happy with my Ruger scout rifle as a staple user. I just dont get encouragement from hearing they arent great at deflecting gas, but then again im not pushing them hard and shooting loads to extract every FPS oit of it, im realistic and cautious. Still its on my mind. I have access to a leftt German Weatherby locally with a crap barrel in 300 wea. Maybe it would be a good canadate to rebarrel to 338 win and have a bit safer reciever. Maybe, but i am not a big pushfeed person nor a Weatherby fan. Still i think of it from time to time.

PA thanks for sharing that I use Lapua brass in my 9.3 X 62 LH Win 70 and RCBS dies fit to my chamber will keep an eye on my brass.

Yeah, no idea why I never felt anything, not that I'm complaining mind you. And hopefully I never get to 'test' it again. One stupid brain fade moment has hopefully taught me to slow down and think things through.

You should note the differences between the CIP specs for 9.3x62 case dimensions compared to new Lapua brass and the stuff you've re-sized. Personally, I'd obtain new dies.

It seems to me that there are a couple of separate considerations here, with regard to how safe an action is. Gas venting is only one of them. Others include the extent to which the action actually contains and supports the case head, with some leaving more exposed/unsupported than others, thereby increasing the likelihood that gas may actually need to be vented. The Winchester M70 and the Springfield are examples of actions which allow more of the casehead to be unsupported than, say, a Remington 700. All well and good as long as the case does its job, but a potential failure path if the case is defective or overloaded. An action which more or less envelops the case head may reduce the likelihood of the case actually letting go in the first place. As well, it may be better able (and failures I've seen support this) to contain the product of a case-head failure rather than directing it out of the action.

Having said that, I think the risk of a case head failing is rather less now than it was when Mauser was designing the 1898 model.

As well, there's how well-supported the primer is, with some actions having a larger amount of clearance around the firing pin than others, and in some cases a more or less direct path to the shooter if the primer fails.

Shear strength of locking lugs is also a factor, but perhaps more important than strength is the work of fracture of both lugs and receiver. A safe receiver, even when grossly overloaded, should bulge and distort plastically, thereby absorbing energy rather than flying to pieces. A brittle failure is much more hazardous because even though the strength may be there the ultimate failure mode does not absorb appreciable energy but instead releases it into flying pieces of rifle. As well, if the rifle really is to let go, the design should, to the greatest extent possible, prevent the bolt and other parts going back into the shooter's head. You see such thinking in the design of actions like the 1898 Mauser, with a lug in reserve intended not to engage when the action's locked, but to prevent the bolt going back into the shooter if the locking lugs fail.

Might just replace all my rifles with Savages. They’re just about the only brand I can find in stock these days. At the very least might replace my Tikka 223 with a Savage 223, since that will be the rifle I will start my son on when he’s old enough to shoot center fire. Or is this worrying all for nothing for someone who doesn’t reload?

Have you seen or heard of a Tikka action blow-up or are you basing your decision on supposition? There was an issue a few years back with some bad alloy in stainless Sako/Tikka barrels but as i do not recall any action blow-up issues.

drover

I’m basing my worries on a lack of information. A lack of bad stories about Tikka rifles does not mean it’s as safe a design as others.

https://www.americanrifle.com/shop/product/mausingfield-bolt-action-2

Scroll down and theres a section on the testing of this reciever and gas venting. At least to me it was interesting

I don't care how good a Savage action handles gas, There so ugly, I cant stand to look at one. RJ

I have retro-fitted the gas block to a few Model 70's I have also modified the bolt to allow a shallow counterbore in the barrel. I don't know if either mod does all that much good but it's something! GD

I thought that too until I ran into my Savage 114 Walnut. I can't stop looking at it

After firing a piece of nosler brass around 22 times, i had a partial case head separation in my kimber 84. No gas blow back. Didn't realize what had happened until extraction. I am now older and wiser, and don't push brass life that far anymore.

Thanks, gte901m. I will still faithfully wear my glasses, but am glad to hear your report. I usually pitch brass after about 6 loadings, just to stay on tbe safe side.

The safest when we ran the test (in 1969) was the Remington 700. The second safest was the Weatherby Mark V.

At the end of the test we tried to see what it would take to blow up a 700. We put multiple 220 grain bullets in front of a factory load. I don't recall the number but it was something like 6 or maybe 8 ea. 220 grain bullets.

The rifle was in a containment chamber, with just big enough hole in the chamber for a string - to pull the trigger. The stock cracked and the bolt was solidly locked into the receiver after firing the round.

I was 52 years younger then and much stronger. I thought I could open the bolt, but I could not.

If a person was holding that rifle with those bullets in the barrel he would not have been hurt.

Those bullets were placed directly one by one in front of the cartridge, no spaces between the bullets. Those bullets did not move perceptively, when the machinists got the bolt out of the receiver.

I mostly have 700's for rifles anymore, I wear safety glasses all the time when firing rifles, even 22's. I do have Mauser's, CZ's, Winchester's, Marlin's, Mossbergs, Tikka's, and Ruger's. I've owned other brands. I am very careful in avoiding over-loads.

The only problem I've had with hot loads:
#1 temperature sensitive powder - I am getting away from heat sensitive powder!
#2 back when I was a pup - Winchester changed from 760-BR to 760 and I took a load from Lyman's 45th manual. Replacing the 760-BR with 760. That 760 load was HOT. It was fired in a Mauser 98 with a 6mm Sharon Barrel. The case stuck in the chamber and the Mauser extractor did not budge it. I'm not sure what dad had to do to get that case out of the chamber. I see that I wrote in that book "DO NOT USE 760 FOR 760-BR!"

I had a Marlin 57 22 LR that in the end shot gases back into my eye upon firing a 22LR. I had fired that rifle a lot. Besides shooting gases back it would often fall apart while in use. I didn't have money for another rifle and I went back to my single shot 22 until I could buy another 22.

In my career as an engineer I was on many safety committees. "Safety is number 1." There is no reason to endanger ones self by intentionally over-loading - getting an extra 100 fps is not worth taking a chance. If your eye sight is worthwhile to you then be careful. I might be overly safety conscious, but I am glad to say that I still have my eye sight. I've made mistakes and I believe that I learned from them.

Stuart Otteson discussed gas handling in his two volume set "The Bolt Action."

That's a really cool book - I wish there was an updated version for the 21st century.

If you read (and comprehend) Otteson's books you'll be able to analyze gas-handling in 21st-century actions.

It might be helpful to remember while handloading that a rifle (or other forearm) is a device which touches off a small enclosed “bomb” inches from our face while hopefully directing the “effluent” out through a tube of small diameter.

I expect there is still much evolution of this process to take place.

I have only had one failure which I discovered after the fact had been caused by a failure on my part. It was a Tikka .222 heavy barrel. I got my face speckled and had maybe 1 drop of blood drawn. Repairs cost me about 1/3 the cost of the rifle. I'm an old man so hopefully I'll never have another experience like that.

Jim

Details please.

These posts scare me. For decades I had assumed that the pre'64 Model 70--the rifleman's rifle--was the pinnacle of bolt actions except maybe for the Weatherby MkV. The only one I have left is a .375 which I load under maximum., With a magnum like that you don't need the last fps of velocity.

I had a batch of 6XC (formed from resizing and fire forming 22-250 cases) that I reloaded 30 times, trying to see how long cases lasted. The load was (calculated at) only 42,000 psi. I thought the failure would be loose primer pockets or split necks. It never occured to me it might be case separation.

The only problem I have ever experienced was with a Savage model 99 in 308. I had just gotten the rifle and was shooting some handloads the previous owner had loaded up. When I ejected the first round, only the case head came out. It was completely separated from the rest of the case. I didnt feel anything out of the ordinary when I fired that round. No gas nothing??

Anyone have an opinion on the Montana rifles safety/ability to handle gas? I've read they are more like the 98 than the model 70 but am not sure how true that is.

Good thread, I did not know that Savages were that strong. I've always liked them.

If you only neck size there's really no reason to have a case head separate. Ditto if you partially size such that the shoulder isn't pushed back, and holds the casehead against the breechface.

Where you see case head separations is where there's clearance between the breechface and casehead, such as where a bottlenecked round has the shoulder pushed back each time the case is reloaded. What happens on firing is that the firing pin drives the case forward, and then the case expands in the chamber to seal and grip the chamber walls, while the thicker head section doesn't expand but instead gets pushed back to meet the breechface. If there's enough room the brass will yeld and you get plastic (permanent) deformation. You thus get a very localised area at about the point where the thicker casehead meets the thin part of the case. about 1/2" or so from the case head, where the plastic deformation occurs - and you can often see it if you look. Each time you push the shoulder back and fire it again, this area gets stretched again, causing it to become thinner and harder, until the case separates at this point. You will also see it in rimmed cases or belted, where there's too much headspace.

You can avoid it by necksizing only, to ensure that the case is more or less against the breechface on firing, such that there's no room for it to stretch enough to yield. Alternatively you could check inside each case for the localised necking of the material with a bent wire, but IMHO it is better to avoid the problem. I've had batches of brass go well past 30 load cycles since I worked this out a fair while back. The main determinants of case life for me are losing them in the field and neglecting to anneal necks and having them split. Sometimes I also have primer pockets get a bit loose after a while.

FWIW this case head separation is a different thing from a case head failure, which is where the case head itself ruptures, such as due to a material defect (which would be pretty rare) or overload/pressure excursion. The case-head separations I've experienced have never been particularly dramatic, and often I only noticed when I couldn't chamber another round.

After living for 34 years in one house we moved. At the new location my reloading press and powder scale had to be mounted differently than previously. I had been wanting to make up some light 40 gr. loads using a fast burning powder. The new angle of the powder from where I sit resulted in an incorrect setting on the scale. My fault I didn't check closely enough to avoid the error. I don't try to blame others for a failure on my part.

Jim

Most Savage 99,s I have loaded for have large chambers I keep the brass, dies, separate, and don't load past med or lo book loads. 250-3000 and other long sloping cases in a 99 you have a lot of case stretch. So I watch the case to prevent case failures.

A modern bolt action, you may want to consider is the Steyr SBS Pro. It is a 6 lug fat bolt design with a SAKOish type extractor. How does it compare safety wise? Dunno since I've no experience with gas coming back at me while shooting it. I don't know if I shouldn't be impressed when Steyr claims proof to 120K PSI, so I am. If you do a search, you will find that it has more than a few positive features not the least of which is how well it shoots. My Steyr SBS in .30-06 is easily the most consistently accurate factory rifle in my gun safe. Not always 1/2 MOA but often enough to think that it could be.