308 conversions

[hunt-m-up]

Hi, I'm new to this site and fairly new to the milsurp fun.  Never having handled one, are the .308 converted Mausers and Enfields the real deal or would they make better circus tent stakes? I'm thinking about a Mauser .308 I saw recently, not sporterized, just re-chambered.
Thanks,

[Swampman]

The Israeli Mausers aren't too bad.  The Ishapore Enfields are not conversions, they were made that way.  If you have access to NATO ammo they may hold up.  Modern .308 commercial ammo can be too hot for them.

Personally I'd avoid the Enfields.

[mcwoodduck]

I had one of the Spanish 308's and it was great. handi little rifle that worked well for me as a swamp gun.  I didn't care about the cheap little thing and on rainy days i would take it into the swamp with me to hunt deer and bear.
Changing the caliber in a mauser is easy as long as you stay with the same base diameter nd do not have to open the bolt face. 

[Mikey]

hunt-m-up:  Welcome Aboard! 

Scroll on down some pages in the forum and you should find lots of discussion on 308 mil-surps. 

Either of the two you mentioned are pretty good mil-surps but they are both old and may not hold up to lots of fun and play the way you might like.  The Enfields are pretty neat but I'm not sure how much of a pounding they will take with the 308 round and I would not use hunting ammo in either the Enfield or the Mauser.  The Mauser may be one of a number of conversions:  older Spanish Mausers converted from 7x57mm to 308, wartime production/capture/surplus 98s in 8mm converted by Israel to 7.62, and probably a few others.  Would I buy one of these for a beater or blaster - not so sure.  When you get into the 308/7.62x51mm arena you find ammo quality and standards vary considerably.  Also with some Mauser conversions you may find feeding problems with anything but ball ammo.  Sometimes you luck out!

If you want something you can blast away with and also hunt effectively with then consider either a Mauser in the original 8mm (which outshines the 308 and is readily available) or a Enfield in the original 303 British (which is my preference over the 308).  You will also find surplus ammo readily available for both the 303 and the 8mm.

Should you wish to go another route you can try the SKS/AK/Saiga route in 7.62x39 or Saigas in 308. 

If you wish to stick with bolt rifles you can always buy a used 308 and shoot tons of surplus in it without worrying about varying pressures.  JMTCW.  Mikey.

[hunt-m-up]

Thanks for the help on this one. I'm not too brave when it comes to exploding metal and flying parts and I would want to try modern hunting loads at some point. I guess that's what my modern bolt guns are for, duh...no wonder my wife says I'm a dozen fries short of a Happy Meal...

I've done the SKS thing, now I'm thinking bolt, maybe Mosin they're a dime a dozen right now and I could do the Bubba to it without feeling too bad...
Thanks again,

[mcwoodduck]

I think there was a misprint. The military surplus ammo and Nato Spec stuff I have shot out of my bolt action rifles have a higher muzzle blast as well as increased speeds.  I think they souped them up a little to make the M60 work or the M14 both gas systems.
The 150 grain soft point federal loads always worked out of the military guns and grouped well.

[Swampman]

7.62X51 NATO is loaded to lower pressures than SAMMI specs for some commerical .308 Winchester.

[mcwoodduck]

OK. 

[Larry Gibson]

I've done considerable pressure testing in 3 different .308 rifles (10, 12 and 14" twist barrels) using a M43 Oehler PBL as of late.  I've ran tests on numerous lots of U.S. M80, M118, M852, Foreign M80 NATO loads, factory ammo (Win, Fed and Rem) and some handloads. 

Some facts;

U.S. 7.62 NATO is not loaded to be "lower than SAAMI specs", it is loaded to U.S./NATO specs.

U.S 7.62 NATO ammo was not "souped up" for the M60 or the M14.  Those weapons were designed to function with spec 7.62 NATO ammo.

I've yet to find any military or commercial ammo that is anywhere near the "maximum" allowable average pressures established by either NATO or SAAMI.

Most 150 gr factory .308 ammunition has a slightly higher velocity and pressure than most M80 Ball and M852.

M118 SB and M118LR pressures are pretty much the same as factory .308 pressures.

All of the U.S. and foreign milsurp .308/7.62 ammo I have tested to date so far have had less pressure than all of the milsurp 7x57 ammo that I have tested in my M95 Mauser.

The factory .308 W pretty much equals the pressure of milsurp 7x57 Mauser ammunition.

Factory (Norma and Hornady) 7.65 Argentine and SF 7.65 Argentine milsurp pressures when tested in my M91 Argentine Mauser are pretty close to the same pressure as factory .308W.

Those are the facts and they pretty much dispell the old wives tales, rumors and assumptions about some of these actions being "designed" only for 45,000 psi and thus will not hold up to ".308 pressures". That old pressure measurement is actually taken off copper crusher systems. It's currently referred to as C.U.P.s.  Todays allowable average psi's (measured with transducers or strain gauges) is 51-55,000 psi for the 7x57 and 7.65 Argentine. 

I've had numerous mausers (M93/M1916 and M98s) that were rebarreled to 7.62/.308W. One M1916 (a 1928 Oveido) has had two .308W barrels shot out on it and is still going strong with another barrel on it.  All of these converted .308s on Mauser actions have shot well but some of the actions have feed rails made for the taper of the mauser cartridges. This causes feeding problems as mentioned. One must load 5 dummy cartridges into the magazine when testing because most feed problems occur with more than 2 rounds in the magazine., mostly on the 1st and second rounds with the magazine loaded.  Some also have feeding problems only from the left side.  This can be corrected but you have to know what you're doing.  Many of the Isreali M98s and Spanish FR8s that are already converted to 7.62 are the most reliable when feeding 7.62/.308W ammo.

Larry Gibson

[Swampman]

These "facts" seem like apples and oranges to me.

[Larry Gibson]

These "facts" seem like apples and oranges to me.

Right you are; the axiom "apples and oranges" most often is used to represent a contradiction.  When factual measurements are taken there is indeed a contradiction with the myths, old wives tales and assumptions that many hold dear.  So which do you prefer, facts or old wives tales?

Larry Gibson

[Swampman]

I think I prefer my facts to be in context.

[Larry Gibson]

I think I prefer my facts to be in context.

Okay, I'll bite, in context to what?  Seems I answered the original posters question and also commented on other remarks in this thread.  How is that not "in context"?  Try an explanation this time instead of just remarking.

Larry Gibson

[Swampman]

I feel your cartridge comparisons are invalid.  You may feel differently.

http://www.thegunzone.com/30cal.html

"Pretty close" makes me nervous when we are talking about pressures and cartridges.

[Larry Gibson]

I feel your cartridge comparisons are invalid.  You may feel differently.

http://www.thegunzone.com/30cal.html

"Pretty close" makes me nervous when we are talking about pressures and cartridges.

Obviously you completely misunderstand; the comparison is between pressures of cartridges and the actions they may be used in, not between the cartridges themselves. The site you refer to is a classic example of the "myth". It attempts to show the mythical difference between the .308 W and the 7.62 NATO by showing the spec difference between military 7.62 headspacing of chambers and those for .308W SAAMI specs for chambers.  That is in fact your "apples and oranges" comparison. The specifications for the both the 7.62 NATO cartridge and the .308W cartridge are the same regardless of differences in chamber headspace.  If you doubt that the two cartridges are dimensionally the same please show us how many reloading dies are available for 7.62 NATO?  You won't find any because they two cartridges are the same and all reloading dies for both are sold as ".308W" loading dies.

I said "pretty much" not "pretty close" BTW. However for all practicle purposes they are the same here.  I did not say exact because the psi readings were not exactly the same. They are close.  The average SAAMI MAP (maximum allowable pressure) for the .308W is 62,000 psi (transducer or strain gauge). For the 7.62 NATO (TM 9-1305-200 dtd June 1961) the MAP for M80 Ball "may vary from 45,000 to 65,000 psi depending on the temperature".  The PAP (peak average pressure) of several different lots of M80 ball at 70 degrees that I tested ran from 50,900 up through 53,900 psi (M43).  Federal, Winchester and Remington factory loads with 150 gr bullets ran from 50,200 to 55,700 psi (M43). The M852 had a PAP of 48,000 psi (M43) and the 3 different lots of M118 SB and LR had PAPs of 49,600 to 55,700 psi (M43). These pressures were out of the 10" twist barrel which is almost new and has a minimal headspaced match chamber. All testing was conducted on the same day from the same rifle.  The barrel was cleaned between strings and 2 foulers fired prior to the 10 shot test. 

None of the factory PAPs approached those of the SAAMI MAP (62,000 psi) for the .308W.  Most do not realise that most all ammo is not loaded to maximum pressure but is loaded to a specified performance level, mostly fps.  Most (perhaps you?) buy off on the myth that all factory and military ammo is loaded to maximum allowable pressures. It just isn't so.

To me the measured pressures are "pretty close". You may not "feel" so but it appears you put more faith in myth than in actual fact.  I'll stick with facts.

Larry Gibson

[Swampman]

"None of the factory MAPs approached those of SAAMI MAP for the .308W."

But they could without our knowledge.

"Most do not realise that most all ammo is not loaded to maximum pressure"

But it could be without our knowledge.  That word "most" really sticks out.

I put more faith in mil specs & SAMMI specs than I do the assertions of someone I don't know.

I still feel your cartridge comparisons are invalid.

[Mikey]

Larry:  Thanks for posting the results of your findings.  I'm sure you well realize many of us had voiced concerns and had advised to the cautionary side when folks asked about the 308/7.62x51 Nato ammo pressures and mil-surp conversions.  I very much appreciate your willingness to share this information.

Swampman:  Discourse on different cartridge pressure comparisons or not, Larry has provided important information.  Do not however discount our concerns about using older mil-surp firearms with new or modern ammo, caution is always advised and your concerns are well noted. 

And again, regardless of action style it is a known fact that the SMLEs chambered in 7.62x51mm are sound actions, as are the Mausers, the SMLEs weigh a ton and if I'm gonna get another Mauser it is still gonna be in 8mm - and that's just cuz I like round numbers..................... and this is just Mikey.

[Larry Gibson]

Thanks Mikey

Always willing to share knowledge.

Swampman

Just how well do you know those guys at all the ammo factories? Or the munitions plants where the milsurp ammo is made?  Fact is, you don't know them any better than you know me.  I'm just posting information that I've actually measured. You may do with it as you want. What you "feel" or that you believe all ammo is loaded to SAAMI or milspecs means little to me. "Most", including you, do believe that. I am just trying to provide accurate information so that the others in "most" may thus have a more infromed idea of what factory and milsurp ammuntion pressures really are.  You've already made up your mind and haven't provided any facts here other than your opinion. That's fine with me but of really little use, eh? 

Larry Gibson

[Larry Gibson]

Mikey

Might interest you that in recent pressure tests in my M95 Mauser in 7x57 Hornady's 139 gr Light magnum had a PAP of 44,200(M43) at 2624 fps (22" barrel). Some milsurp PS 1950 ammo (loaded with a 154 gr fmj over 39 gr of the typical German flake powder in Berdan primed cases) had a PAP of 59,400 (that is not a typo) psi(M43)!  Velocity was 2442 fps with an ES of 114 fps which isn't bad for a 10 round test string of milsurp.  Quite a difference in pressure there but I have shot close to 600 rounds of that milsurp ammo over the last few years.  Never was there any hint of over pressure signs with the case/primer or in opening the bolt. SAAMI MAP for the 7x57 is 51,000 psi.  Was down to the last 20 rounds before I set the M95 up for pressure testing....I guess ignorance is bliss!

The old classic load of a Hornady 175 gr RN over 49 gr H4831 (WW cases with WLR primers) ran a PAP of 51,800 psi (M43) at 2405 fps out of the 22" barrel.  Accuracy was 5 shots in 1.25" at 100 yards with the aperture rear and post front sights. 

Larry Gibson

[Mikey]

Larry - thanks, I appreciate the information.  I recall reading somewhere, possibly even in a post from you, that some mil-surp ammo generates higher than normal pressures after being stored for long periods of time.  I think the ammo involved may have been Turkish made 8mm for their Mausers but I am not sure. 

I guess the question is: from a powder/pressure perspective, does the degradation of powder over time result in variations in burning rates that could spike pressures dangerously???  Good question, I think.  Mikey.

[Swampman]

"What you "feel" or that you believe all ammo is loaded to SAAMI or milspecs means little to me."

What I feel or believe doesn't matter period.  The specs are there as a safety guide line.  Advising people in a public forum to ignore them is a good way to lose everything you own.

Maybe, almost always, and probably, isn't really going to help a guy with fingers & part of his skull missing.

[Larry Gibson]

Larry - thanks, I appreciate the information.  I recall reading somewhere, possibly even in a post from you, that some mil-surp ammo generates higher than normal pressures after being stored for long periods of time.  I think the ammo involved may have been Turkish made 8mm for their Mausers but I am not sure. 

I guess the question is: from a powder/pressure perspective, does the degradation of powder over time result in variations in burning rates that could spike pressures dangerously???  Good question, I think.  Mikey.

Mikey

that is a very good question and one that always concerns me when shooting older milsurp ammo.  I always pull a quanity of bullets and look for any signs of powder degradation.  Usually it is noticeable with off colored powder, really smelly fumes and corrosian around the bullet in the neck.  I have found some of that.  However, in this particular case with the PS 1950 7x57 there was none of that.  I intitially chronographed it over my Oehler M35P when I got it and the velocity was basically (no swampman, they are never exactly the same) as with the last test over the M43.  The ES and SDs were essentially the same also and well within spec for milsurp ammo.  Checking with numerous sources found the velocity I got should have been the expected velocity from a 22" barrel. Thus there wasn't any indication that the powder had degraded.  I always check as mentioned though.

Larry Gibson

[Larry Gibson]

"What you "feel" or that you believe all ammo is loaded to SAAMI or milspecs means little to me."

What I feel or believe doesn't matter period.  The specs are there as a safety guide line.  Advising people in a public forum to ignore them is a good way to lose everything you own.

Maybe, almost always, and probably, isn't really going to help a guy with fingers & part of his skull missing.

Holy cow Swampman!

I'll ask you to go back and reread my posts and then tell me where I was advising people to ignore anything.  I believe I was informing people of what I found by actual tests and measurements vs guestimating by using a "guide". There is quite a difference you know, one is fact and the other an assumption. As to my use of a M93 for the .308W I first made the conversion ('68) when it was common. Back then the only superiority of the the M98 vs the M93/M95/M96 was the LR and cock on opening.  P.O. Ackley and numerous other experts of the day made such conversions on M91 and M93 Mauser actions.  Seems the advent of internet forums has made everyones opinions as fact.  I did not advise anyone to make the conversion, I only stated what I had done.  I also converted the M93 to cock on opening which may cause serious palpulations of your heart also.

Yes, the specs are there as a safety guide.  A guide is not an absolute BTW.  You might also note that what I really pointed out was that by simply buying milsurp ammo of 7x57 or other milsurp cartridges doesn't mean you are safely within the "guide".  I also pointed out the myth of a difference between the 7.62 and the .308.  Publishing tested facts will not lose me "everything I own".  Your "sky is falling and we must tell the king" attitude not withstanding.

Larry Gibson

[cbxboy]

Getting into this late but had to comment on 7.62x51 NATO and .308 commercial load.

What a deep hole to try and dig yourself out of (that inclues us all in this topic) a belief we have.  The point is we have a differing belief.  Repub vs. democrat comes to mind, did we really land on the moon...etc.

For what it is worth my reading .....it was a while back......came to the concluion that the 308 and Nato were never tested under the same circumstances.  So easy enough to me that if someone tests chamber pressure in the exact same manner we have an outcome. 

Owning many milsurps I know as a fact every dang time I squeeze the trigger I am firing a tool which is 70+ years old in most cases.  Am I expecting perfection???  No.  A Model A truck did not have seatbetls, had a plate glass window, and road like a buckboard.  Should we compare to a 2008 Benz??

My point is that myths will exist, only you pull the trigger.  I assume all safety for myself when I shoot old Turk ammo (5,000 rounds plus now) and Yugo, Greek, Indian etc......I also know that when I shoot hte 1916 Spanish convert I have a choice of what I put in the chamber.  I shot Remington .308 150's....or Radway Green Nato.  It made no difference to me.  As I now reload for ,308 I would CHOOSE to shoot a whimp load.....more because I find it enjoyable to shoot 60 rounds and not fell it so bad.  The though of exploding woudl still wheigh in my mind.   Now my minty FR8 only gets puffballs as I would hate to have it blow up

Do what you are most comfortable with....I don't pay for your ammo.

[Swampman]

My point being the specs aren't myths.  They are limits within which the cartridge's pressures  should fall.  The rounds may or may not be loaded to max spec.  There is no way to know even after you shoot 500 of them without a problem.  They could be like proof loads for the gun they are being fired in.  Most guns will contain quite a few proof loads but eventually problems will arise.  Of course this post is a waste of time and it will be disputed buy someone who has tested a few lots of ammo in a few chambers.

Maybe, almost always, nearly all the time, it will be ok to ignore the specs.

[Larry Gibson]

My point being the specs aren't myths.  They are limits within which the cartridge's pressures  should fall.  The rounds may or may not be loaded to max spec.  There is no way to know even after you shoot 500 of them without a problem.  They could be like proof loads for the gun they are being fired in.  Most guns will contain quite a few proof loads but eventually problems will arise.  Of course this post is a waste of time and it will be disputed buy someone who has tested a few lots of ammo in a few chambers.

Maybe, almost always, nearly all the time, it will be ok to ignore the specs.

By the way, I've tested more than "a few lots of ammo in a few chambers".  How many have you tested? How many different chambers do the ammuntion makers use?  I never said that the "specs" (I'm assuming you refer to ANSI and SAAMI "specs") were myth.  What the myths are is the misconception of the "specs" that many people have and are perpetuated on the internet, in magazine articles and person to person.  Can you show me anywhere in the data that I posted where cartridges tested did not fall "within the specs"?  Fact is you can't because I didn't. I didn't because all of them were within "specs".  See, we are in agreement!

If you want to believe that 7.62 NATO is loaded hotter or colder (we see it both ways in these forums) because of chamber spec differences between SAAMI chambers and military chambers that is your choice.  I merely have presented some fact based on what both 7.62 NATO and .308W do when the pressure is actually measured and not guessed at.  BTW; you still haven't answered specifically how I "ignored the specs". It appears you just want an arguement and unless you can be specific (other than "Maybe, almost always, nearly all the time, it will be ok to ignore the specs") then I believe our conversation is over.

Larry Gibson

[Larry Gibson]

cbxboy

"For what it is worth my reading .....it was a while back......came to the concluion that the 308 and Nato were never tested under the same circumstances.  So easy enough to me that if someone tests chamber pressure in the exact same manner we have an outcome." 


That is precisely what I have done. I have fired numerous lots and types of 7.62 NATO and numerous factory loads of .308W through 3 different rifles measuring the pressure.  Each lot was fired in all three rifles so there is a direct comparison as they were all "tested under the same circumstances".

The pressures of that Turk ammo you've fired might surprise you. Swampman would probably have a heart attack!  If  you have only the M1916 converted Spanish rifle it is an FR7. The FR8 is based on the M98 action. If you've a "minty" one of those they are sweet rifles. Mine was minty only in the metal so I modified it into a "scout Rifle" and it functions perfectly in that guise.

Larry Gibson

[cbxboy]

Larry,

The 1916 I recalled (let it go in a deal) was not the FR7.  My memory is getting bad as I was trying to move away from so much "gun time"....I may be wrong.  It was original in 7x57 and rechambered to .308 NATO.  I have never owned an FR7 (yet) but am confident it was not an FR-7.    I just popped over to GB and it was a 1916 Spanish Mauser in .308 Nato convert Civil Guardia with the crossed swords.  Nice to have memory prompters.

The FR-8 was a dream rifle from a guy who was moving and I bough 7 or 8 of his pieces.  A Milsurp collector who started early and had all primo examples.  The FR-8 IS INDEED a sweetheart.  One of my favorites and the value in itself would not make it my most expensive   I had also considered a "beaten" rifle to use as a shooter but passed on it.  Too many field mods already done.

Larry, I'm with you in the respect that each time we pull the trigger we have no guarantee of safety from ANYONE.  I have seen factory ammo blow up -- not american made...but factory.  Swampman is correct in the statement that a tool will hold up repeatedly until it doesn't, 100% agree.

So......anyone wan't to shoot my Carcano TS 8mm conversion with Turk??  I have some nice 1944 Turk which really bangs hard???    It's perfectly safe you know (sorry couldn't resist opening the can...no reply needed)

[Larry Gibson]

cbxboy


I agree, there are some differences between the FR7s and the M1916s converted to 7.62.  Of all I've seen the M1916s were the better finished and probably better quality.  Sounds like a really sweet deal you got there, I've stumbled into a couple like that over the years.  Yup, we both agree with swampman on tools holding up until they don't.  I've asked repeatedly where documentation could be found that the M91, M93, M95 and M96 Mausers were "designed" for only 45,000 psi (that would have been based on the CUP measurement method. It would correlate to (most ballisticians believe there is little correlation between CUP and psi) 51-54,000 psi using modern methods of pressure measurement).  As mentioned, I recently tested some Hornady 7.65 (imported) Argentine ammo. I'm sure Hornady knows it will be shot in a lot more M91s than M1909s.  The average psi(M43) was 53,2000.  I do shoot a lot of milsurp ammo in my rifles but I like to really check it over and conduct some testing before I shoot a lot of it.  Like you, and swampman for that matter, say; better to be safe than sorry.

Larry Gibson

[Swampman]

You merely have presented some "fact" based on what both 7.62 NATO and .308W (might do, or could do, or sometimes does, depending on the lot it ought to do)when the pressure is actually measured and not guessed at."

Better safe than sorry.