No.4 300 Winchester Magnum Test

I've decided to try the limits of the action with some "real world" tests.

So, the caliber is going to be 300 or 303 Winchter Magnum, depending on the donor barrel, as brass is readily available (I hope) and the rim size is compatible w/ the existing bolt and extractor.

Need to set some parameters first.

Prefer to use factory ammo at first, as long as a reasonable supply can be found of partial boxes and such at the local gunstores. (If running a 303 bore, I've a large quantity of 174gr hpbt Sierra match bullets that I have no use for ootherwise as they're moly coated- if there are no objections those would be the default bullet.)

Dry cases and chamber for at least the first 100 rounds or so.

Questions:

-Headspace on the belt or the shoulder? (the second option tends to limit factory ammo to one brand as they aren't uniform- from past experience.)

-O-ring on the first shot or no? (This isn't a brass life test, but if it runs on a while I think my wallet could use the help,)

-POI observations or no? Not a great concern to me unless it indicates progressive failure of the action. Its a bother to do on a remote fire test rig.


i'd like to keep it as simple as possible, takes away from range time otherwise "productively" spent, plus I haven't a scadillion dollars- this is mostly a thought (read "costless") experiment gone horribly "real".:yikes:

Mr. Jmoore

1. Use the .300 Winchester Magnum, the case has more surface area than the .308/7.62 and has better “grip and traction” in the chamber.
2. No rubber o-ring and .016 head gap clearance, the dry case will stretch and absorb over 50% of the increased bolt thrust.
3. Wake me up when the test is over, the .300 Winchester Magnum only has 2,000 PSI higher chamber pressure than the .308 Winchester.

Why don’t you perform this test instead, use the .308 Winchester as the test cartridge, set the head space as close to minimum as possible and fire 100 oiled cases and check the actual headspace with a spent primer. Fire 100 more oiled cases check head space, etc. etc.

“An appeaser is one who feeds a crocodile, hoping it will eat him last.”
Winston Churchill

I'm copy-ing myself from an old post as my likely chain of degradation/failure. I'm curious to see if it works out as follows:

Quote:

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Probable failure order of a No4's structural components:

1.Bolt head-
A)first excessive overturn (common)
B) then, fracture at the thread terminus (No No4 examples on hand, but I've several SMLE bolt heads broken off at this point.)

2.Bolt -
A) Forward face wear takes out most of these, I think.
B) Also the small lug in the striker cam area sometimes fractures- seen a few of those.
C) Bolt lug wear
D) Bolt lug shears off LH side - Never seen or heard of it though!

3.Receiver Body-
A)Bolt lugs wear through the hardened mating surfaces- Caught upon inspection- no real danger here.
B) Fatigue failure of RH receiver rail. Rifle contiues to function-sort of -probably begins to bind up on cycling and POI/accuracy go out the window.
C) LH receiver wall fails- a bad day! But there ought to be all the warning signs above.

Pure speculation, though. Tear this argument to shreds if y'all wish!

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Why not just make your own proof or over proof 303 rounds and use plenty of oil. A lot cheaper easy to do and much simpler.

Bindi2-No way to control or check chamber pressures when going past what's in the manual.

Mr. Horton-As to the chamber pressure being only moderately higher than 308W that's OK. I thinking the larger base ought to add some more thrust area. Shall we start boring math stuff already?

General poop-300 WSM is an option, but more pricey- want to contribute supplies or funds? I'm not proud...

Found a nickel plated M1917 barrel- Enfield rifling, but of "300" size, and easily threaded w/o shortening or other tricks. OK?

Mr. jmoore

They made a movie about what your doing back in 1956. The name of the movie was called "The Enfield That Never Was". Clifton Webb put a life preserver on a dead Enfield cadaver and let it float ashore to fool the Germans during WWII.

This subterfuge was called "Operation Mincemeat" and the side that used the Enfield won the war. To make this test realistic you will need to handcuff a briefcase to the trigger guard and put all the Enfield manuals in it from the Knowledge Libraries.

P.S. I spoke briefly to the Finance Minister and she said there's no way she would invest money in a movie remake unless Clint Eastwood has a staring roll. :thup:

P.P.S. I contacted the prop department and they said it would be impossible to make a Mosin look like an Enfield for the new movie. This means we will have to go to the expense of computer generated graphics and use a lot of new boring math stuff calculations. :eek:

Are you sure you want to go to this expense when we already know who won the war. :rolleyes:

Quote:

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Originally Posted by jmoore

Bindi2-No way to control or check chamber pressures when going past what's in the manual.

Mr. Horton-As to the chamber pressure being only moderately higher than 308W that's OK. I thinking the larger base ought to add some more thrust area. Shall we start boring math stuff already?

General poop-300 WSM is an option, but more pricey- want to contribute supplies or funds? I'm not proud...

Found a nickel plated M1917 barrel- Enfield rifling, but of "300" size, and easily threaded w/o shortening or other tricks. OK?

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Well I for one am quite interested in seeing how this turns out. The M1917 barrel sounds like the way to go. I'm just wondering if you are able to Magnaflex (sp??) the receiver before and after to see if any fatigue/stress cracking shows up and where.

Mr. jmoore

All kidding and joking aside, the British forum members are being hammered with vague comments about the strength of the No.4 and the 7.62 NATO cartridge.

The British military still to this day use the oiled proof test cartridge to proof their military small arms. This amounts to a 40% to 50% increase in bolt thrust from firing a dry cartridge. The first indication of excess bolt thrust would be a increase in head space.

Why not fire a .303 100/200 times with wet cartridges and check headspace, if their is no increase then do the same test with oiled cartridges. Then repeat the test with the .308/7.62 and see where we stand.

If I'm wrong I will send a new bottle of Caster oil to Mr. Parashooter and if I'm right Mr. Parashooter can send me one of his Enfield's with the tightest head space :yikes: (just kidding) :D

I think this type testing would be in the "Myth Buster" category and give us some real world answers. I will donate 200 Greek HXP cases for testing purposes and others can chip in as they see fit.

When the testing is done we can write a book on the subject and then all of us will be rich and famous.

Here is what I think the new book should look like. :rolleyes: What do you say Mr. jmoore should we give it a go?

https://www.milsurps.com/images/impo...dummiesa-1.jpg

A little off topic, but has anyone seen or have a copy of the video made by UK MOD showing a N04 firing a round loaded with PE4 explosive?

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Originally Posted by Brit plumber

A little off topic, but has anyone seen or have a copy of the video made by UK MOD showing a N04 firing a round loaded with PE4 explosive?

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Why bother? Salting explosives-loaded ammunition in enemy ammunition dumps is nothing new. So, just who is the enemy in all this testing?

I am curious why tempt fate rechambering a No.4 to .300 WM, when P14s in .300WM are a well known and long trusted conversion?

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Originally Posted by Maple_Leaf_Eh

Why bother? Salting explosives-loaded ammunition in enemy ammunition dumps is nothing new. So, just who is the enemy in all this testing?

I am curious why tempt fate rechambering a No.4 to .300 WM, when P14s in .300WM are a well known and long trusted conversion?

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The argument from the NRA is that No4 actions are 'suspect'

There would be little point in using the argument that a P14 is 'OK'.

Compare Apples to apples !!!

Mr Horton, I can send your local dealer a several SMLE barreled actions if you want to do the oiled 303 tests. I'll even throw in a suitable "Bubba'd" buttstock you can use as an attach point to whatever holding platform you construct.




I don't have a pile of No.4 barreled actions, just a few, and some of that is going for test purposes on my end.

As far as NDT goes, visual inspection and dye penetrant inspection can be performed on site. MPT and/or eddy current (plus need test samples made for this) tests aren't as feasible as the local hot rod shop moved about 90 miles away. Don't know of another "cheap" and easy source available that I can drag firearms parts into w/o drama.

Headspace testing can be done as well, but I'm thinking of making the barrel adjustable like a Savage 110 to keep case head separation issues minimized. I want to see how much the action will take under as uniform conditions as possible before something major fails. Bolts and bolt heads I think are the weak link, so I may have to round up some spares and fit them as required.


Don't know how long all this is going to take, folks! I hope y'all have long attention spans...

I'm having a "bit" of trouble removing the '44 LB barrel from the selected action. The barrel vise is mounted onto a 1" plate table that's welded to a 12" column, so the support is rigid enough. Have used cheater bars, a 3lb sledge hammer, heat, penetrating oil, and combinations of those. Clamping bolts are tight enough that the 1/2-20 threads are starting to let go and I'm afraid that the wrench is going to break!

Letting it soak for several days in pentrating oil, if that doesn't work, might have to "ring"the barrel just fwd of the action w/ a parting tool. Really don't want to, as it's OK otherwise.

I've pulled a few barrels before, but never had an Enfield give so much trouble! Even got WBS2111 in on the "action", and together we still couldn't budge it. Errrr.

So: "Delays. delays!" (Marvin the Martian)

I had the same problem with a 1943 No.4 Mark 1* LB. Eventually I had to choose between saving the receiver or the barrel :)

I read somewhere that they were fitted hydraulically (whatever fiendish device that was), but it sure puts the barrels on tight.

This either a spoof or just plain nuts, (and besides you will continue to rile up our resident curmudgeon, the infamous head space pro Edward Horton!), please stop!

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Originally Posted by shottist

This either a spoof or just plain nuts, (and besides you will continue to rile up our resident curmudgeon, the infamous head space pro Edward Horton!), please stop!

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https://www.milsurps.com/images/impo.../chclogo-1.jpg

Both cut and pastes are from the British "Textbook of Small Arms" 1929 War Office Manual and were printed before we were born. ;)

Read number 4

https://www.milsurps.com/images/impo...4/repair-1.jpg

Below greatly effects number 4

https://www.milsurps.com/images/impo...4/TBOSA2-1.jpg

And the curmudgeon didn't write it. :thup:

"This either a spoof or just plain nuts"

P.S. Mr. jmoore isn't nuts, he is just bored because the CNC machines do all the work and he is suffering from overexposure to heavy metal discharge vapor. Keep up the good work Mr. jmoore but I think you would learn more by shooting oiled .303 cartridges due to their more tapered shape.

Signed
The Cranky Old Fart

Some how i think EDs comment about oiled tapered cases is spot on and easy to do.

Quote:

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Originally Posted by jmoore

I'm having a "bit" of trouble removing the '44 LB barrel from the selected action. The barrel vise is mounted onto a 1" plate table that's welded to a 12" column, so the support is rigid enough. Have used cheater bars, a 3lb sledge hammer, heat, penetrating oil, and combinations of those. Clamping bolts are tight enough that the 1/2-20 threads are starting to let go and I'm afraid that the wrench is going to break!

Letting it soak for several days in pentrating oil, if that doesn't work, might have to "ring"the barrel just fwd of the action w/ a parting tool. Really don't want to, as it's OK otherwise.

I've pulled a few barrels before, but never had an Enfield give so much trouble! Even got WBS2111 in on the "action", and together we still couldn't budge it. Errrr.

So: "Delays. delays!" (Marvin the Martian)

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Go for the parting tool, had the same trouble few weeks back, i wanted the action but also the barrel, so i could relign it to .22

Just before the barrel removel took a measurement to give a rough guide so i could knock up a spacer, made the spacer to size plus a midge,s dick, just saves time for when i come to use the barrel.

Sounds an interesting project, Looking forward to the results.

Go for it. You can easily Magnaflux the recever with a decent horshoe magnet and some grinder left overs.

I don't run the CNC stuff anymore, but it took about three years to escape its "evil"(read: either boring or tearing your hair out) grasp. Right now I'm waiting for a part to cool after having been "shrunk" onto a fixture. (Seems like a right good waste of eight years of engineering school, but it's really just a hobby gone horribly "wrong".)

Anyway, this is no spoof, I just reckon if the action can withstand repaeted firings w/ 300WM, then 7.62x51 is no worries...Unfortunately, I've no real use for the magnum caliber- deer die just fine using 55gr 223 rem loads- 303/7.62 seems a bit overpowered now.

Interesting project and I'll be watching for results, but my experience in these things is that many sceptics will remain unconvinced, as solid evidence is rarely sufficient for them to cease clinging to their beliefs. I did some proof testing of a Carcano a while back (posted here) and the "fact" that it's a weak and dangerous action remains a fixture of gun folklore.

You'll go to all that trouble and expense, fire 100 max loads through it and it will remain intact, but it will still be considered unsafe for conversion to 300 Win Mag.

Why not leave it in 303 Brit, and load up full cases of progressively faster powder under the 174 gr bullet (e.g. start with 4350 and work down to 4198)? I could not get the Carcano to come apart with a full case of Unique, but the cartridge did come apart.

If you know anyone that has an Oehler 43 you could have transducers mounted on both sides of the receiver and on the barrel. This would permit comparing the reaction of the receiver and barrel to the firing loads.
I would like to see how many reloads you can get out of .... say 5 new cartridge cases when chambered in the new round of your choice.
I think a .300 RUM with the rim rebated to match the .303's diameter would be a more interesting test.

Feel free to run whatever tests you care to do!

300WM was chosen as a rather large incremental step up using factory and known reloads. I'm not worried about overpressure experiments, rather its a question of whether the action is suitable for 7.62x51 usage in a general sense. (I'm well convinced, obviously, as I not only shoot L42a1s but 2a1s as well!) Even when I worked for a firearms mfg. we had no access to strain gages, but I have used them at the "institute" many moons ago. If anyone knows how to lay hands on such equipment w/o spending a fortune, I'll jump on board. (No research grants from this forum are there?)

If the action holds up to standard loads, then I'll try some oiled cases. Pressures will remain "standard", however!


BTW and ETA- Another reason for 300WM is that I've 60-80 factory rounds already and no rifle. Brass is easy to come by, and I can borrow some reloading dies. 300WSM- 20rds maybe and no brass. Other calibers- Nadda! If someone wants to contribute 100rds factory ammo and reloading dies in the caliber of their choice, I will certainly consider it. Just making do, and all...

Andy, Parker Ackley, who was a very decent fellow by the way, did several blow up tests on many different service rifles. The Carcano was one of them. He was amazed at how strong the action really was. It was stronger than the P17 and Springfield 03 actions. The only reason the cartridge was loaded to the pressures and velocities the Italians chose is just that, they chose to keep it mild for several reasons, the SD was very high and the wear and tear on both the rifle and soldier was less. The Austrians, through Steyr, built many Carcanos in 8x57JS. I have one of those and if I recall, so do you.

As far as using progressively faster powders goes, many moons back, when we were more adventurous, we replayed one of Ackley's experiments. We rechambered a 6.5 Arisaka carbine ($5) that was in less than fair condition to 30-06 in the original 6.5 barrel. We just jumped directly to his final test. Loaded the 30-06 cartridge with 150gr fmj over as much 2400 powder as we could stuff into the case. We tied the rifle to a logging truck tire and let her go. There was a bunch of smoke and flame, out of every nook and cranny. The stock was split and shattered as well BUT the action held together. The bolt wouldn't open, even with a hammer and some brass from the case had flowed around the bolt head and out the gas vents.
We had to mount the rifle in a lathe and cut back the barrel shoulder to get the barrel off. The really amazing thing about the whole thing is that the action was still sound. It didn't set back the lugs or ways and didn't stretch the action. The bolt was fine. In fact that action is still in use to this day as a 308Win. The other gent involved in the experiment was so impressed that he used the action to build up a hunting rifle.

I know, an old story and others besides myself have done the same thing but I think it's appropriate in this case.

Personally I'm quite interested to see how this will pan out, with the Lee Enfield.

:banghead:Barrel off! Good grief!!:move eek:!

:surrender:Finally gave up and cut a ring up against the receiver to roughly 1" dia...

Barrel promptly unscrewed w/ just finger pressure.:lol: Threads OK, no distortion, penetrating oil all over 'em.

Now: The cobble-ing commences.:madsmile:

(ETA This is what you get after I've been up for 23 hrs. Oy.)

As long as the brass used is in good condition it will just stretch with the action. Nothing much will happen, even with oiled cases. However if they are reloaded look for the cases to give it up quickly.

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Originally Posted by jmoore

Feel free to run whatever tests you care to do!

300WM was chosen as a rather large incremental step up using factory and known reloads. I'm not worried about overpressure experiments, rather its a question of whether the action is suitable for 7.62x51 usage in a general sense. (I'm well convinced, obviously, as I not only shoot L42a1s but 2a1s as well!) Even when I worked for a firearms mfg. we had no access to strain gages, but I have used them at the "institute" many moons ago. If anyone knows how to lay hands on such equipment w/o spending a fortune, I'll jump on board. (No research grants from this forum are there?)

If the action holds up to standard loads, then I'll try some oiled cases. Pressures will remain "standard", however!


BTW and ETA- Another reason for 300WM is that I've 60-80 factory rounds already and no rifle. Brass is easy to come by, and I can borrow some reloading dies. 300WSM- 20rds maybe and no brass. Other calibers- Nadda! If someone wants to contribute 100rds factory ammo and reloading dies in the caliber of their choice, I will certainly consider it. Just making do, and all...

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delete

I have read it several times including the predicted failure modes.
I was just going on record that the 300 Win Mag with factory ammo will prove nothing except that the #4 will withstand the firing just fine. The #4 is plenty strong enough to last as many rounds as you can afford.
The only thing that fails is the brass when it is reloaded....

It's a really ugly 30-06 as of this afternoon. Now to install enough parts to get it in firing order, and do a quick test next week. Hopefully!. Then, reamer rental time.

Bolt heads all fail the "overturn" test right now, going to sort that as well.

JM, you're wasting your time. PO Ackley already did the destruction tests a long time ago.

They tell nothing relevant to this "debate".

Why don't you get a nice 1950s No4 Mk2 and strip off the wood, set it up in a fixed rest with remote trigger release, arrange a garden hose to spray a mist of water over the bolt and magazine and fire off as much .303 as you care to waste?

You can check the HS with HS gauges and feeler gauges at the start and after every 10 or 100 rounds.

Having done that, you can proceed to do the same in 7.62mm.

My guess is you'll waste a lot of ammo and determine nothing, but if you want a relevant project, that would be it IMO.

Two scans from the Textbook of Small Arms 1929. I think they speak for themselves, but the obvious conclusion is that could the base of the cartridge be made strong enough, and the blowing out of gasses through the primer holes be prevented, rifles could be fired without any kind of breech block or bolt at all, assuming there is no grease or oil present in the chamber. I notice that there is no reference in the Textbook of Small Arms 19129, at least not that I have seen, to any such issues surrounding the presence of water in the chamber.

If anyone else has noticed such references in their reading I would like to hear the details.

You do that, I'm already well into this silliness.

Everything else I do to waste time costs more!:lol:

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Originally Posted by Surpmil

JM, you're wasting your time. PO Ackley already did the destruction tests a long time ago.

They tell nothing relevant to this "debate".

Why don't you get a nice 1950s No4 Mk2 and strip off the wood, set it up in a fixed rest with remote trigger release, arrange a garden hose to spray a mist of water over the bolt and magazine and fire off as much .303 as you care to waste?

You can check the HS with HS gauges and feeler gauges at the start and after every 10 or 100 rounds.

Having done that, you can proceed to do the same in 7.62mm.

My guess is you'll waste a lot of ammo and determine nothing, but if you want a relevant project, that would be it IMO.

Two scans from the Textbook of Small Arms 1929. I think they speak for themselves, but the obvious conclusion is that could the base of the cartridge be made strong enough, and the blowing out of gasses through the primer holes be prevented, rifles could be fired without any kind of breech block or bolt at all, assuming there is no grease or oil present in the chamber. I notice that there is no reference in the Textbook of Small Arms 19129, at least not that I have seen, to any such issues surrounding the presence of water in the chamber.

If anyone else has noticed such references in their reading I would like to hear the details.

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The British Military and the War Office have long ago figured out how much more bolt thrust you will have with grease, oil or water in the chamber. Please read below, this equates to a 52.6% to 63.1% increase in bolt thrust with oil or water in the chamber of the Enfield rifle. It also states to remove all grease from the chamber if the action is not to be strained.

From "The Textbook of Small Arms" dated 1929

https://www.milsurps.com/images/impo...4/TBOSA2-1.jpg

From E.G.B. Reynolds

https://www.milsurps.com/images/impo...reynolds-1.jpg

https://www.milsurps.com/images/impo...062407PM-1.jpg

https://www.milsurps.com/images/impo...062535PM-1.jpg

Jim Sweets "Competitive Rifle Shooting". Dated 1946

https://www.milsurps.com/images/impo...5/Sweet3-1.jpg

https://www.milsurps.com/images/impo...5/Sweet4-1.jpg

With the .300 Winchester Magnum you aren't just reinventing the wheel, you are putting a rocket motor on Ben Hur's wooden chariot. :banghead:

You are planning to use a cartridge case with more surface area and a larger base diameter than the .303 British or 7.62 NATO.(A large unknown without proper test equipment) The larger base diameter of the .300WM creates MORE bolt thrust due to its larger diameter. Therefore you are not even comparing apples to oranges and now you want to throw a watermelon into the mix and compare that to smaller fruit. :bitch:

The issue is how much damage will continued firing of the Enfield rifle with water, oil or grease in the chamber will actually do. Or how fast and how much will the head space increase with the additional bolt thrust using a .303 or 7.62 cartridge when the cartridge case is not gripping the chamber walls. (With over a 50% increase in bolt thrust) :rolleyes:

Old Engineering term "KISS" or Keep it simple stupid ;)

Added thought Mr. jmoore, fire up your synaptic network and stimulate your gray matter. :D

Guess which end of the bolt is effected the most by bolt thrust and which end does head space increases the fastest. Go ahead and think about it and then think about it some more. (You replace both bolts and bolt heads to decrease head space)

https://www.milsurps.com/images/impo...IMGP2164-1.jpg

https://www.milsurps.com/images/impo...rturnmax-1.jpg

Hm, No1 bodies fracturing due to wet cartridge cases and chambers?

I'm a bit sceptical based on a little thing called the Western Front, 1914-1918.

And then of course there's S.E. Asia Command 1941-45.

Peter, any stories of fractured No1 bodies due to wet ammo or chambers from the older armourers of your acquaintance?

Surpmil

I didn't write the material I cut and pasted here and I do NOT want anyone to think I belong to the "Inherent Weakness" club.

The 1929 British "Text book of Small Arms" tells you military firearms are built at least twice as strong as needed. And they still warn you to remove all grease from the chamber before firing or the "action will be strained".

Even today the United States Military tells its servicemen to NOT lube their ammo or damage to the firearm can occur.

The question isn't "if" water, oil or grease is in the chamber will cause damage to the rifle, the question is "how long" before damage occurs.

You are talking about a 50% increase in force or thrust on the bolt face and how much longer a military rifle can take this abuse.

The "Text Book of Small Arms" pressure figures are not thrust figures written on a piece of paper or bolt thrust figures spit out in a computer program. The British used until recently the "base crusher" system of measuring chamber pressure. This "axial" base crusher system measures chamber pressure that would be actually exerted against the bolt face.

And in 1929 the British War Office tells us to remove all grease from the chamber or the "action will be strained".

The question is how much "extra strain" is too much and what will happen to the bolt and receiver over time with this "extra strain".

The answer is right before our eyes, they made replacement bolts and bolt heads to "repair" excess head space.

The manual below states that if the bolt closes on the .074 head space gauge with a special test #3 bolt head and a new bolt the Enfield is to be turned in for FTR or overhaul. (and something caused this excess headspace) ;)

https://www.milsurps.com/images/impo...ugefile2-1.jpg

I've several SMLE bolt heads that are broken off at the end of the threads (found 'em in bolt bodies).

Mr. Horton, I believe I've already postulated earlier in this thread and in another that I expect the front of the bolt to be the area of highest loading and subject to failure first.

I really don't care about the wet/dry chamber controversy so much as the British NRA's contention that the No.4 action is unsuitable for whatever 308/7.62x51 loads you care to feed it. I'm not looking to induce catastrophic failure so much as to see in an accelerated sense what WILL go "wrong" and if there are tell tale warning signs that the "average Joe" can detect. Since 7.62x51 has been used in this action for a "while" (1960's to start- 1970s in largish quantities and w/ high round counts), it seems that a futher step up is needed to see, in a reasonable amount of time, what the progressive failure mode might be.

I, quite frankly, don't expect a whole lot to happen in this test under normal operating conditions. If I get bored trying to wear it out, then that's a GOOD thing!

Say, if you want some fun JM, why don't you try this: thoroughly oil the bolt and chamber of a Ross MkIII and fire a couple of hundred rounds off and see if the HS changes.

In The Ross Rifle Story there is an interview with a Sgt. Bill Carey, MM* (that means he won the Military Medal twice), who "...one fateful afternoon at Courcellette...fired some 200 rounds in rapid succession, single handedly wresting frontal control from the enemy's line to his own. His explanation for a perfectly performing Ross rifle that day was simple: "Before I started shooting, I emptied my oil bottle into the breech."

Now I wonder if Sgt. Carey knew something about case adhesion and was taking care to make sure that if the ammo was soft or oversize, it wouldn't stick in the chamber. He did say in the interview that in his use of the Ross in WWI, it "never once jammed," but neither did he usually oil his bolt and chamber. Probably as a sniper he chose his ammo carefully.