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ldsparamedic
10-26-2009, 10:22 PM
I have a Savage model 99 in .308. I have a bunch of "military bulk" .308. I fired one round of the military in the Savage and the casing got stuck to the point it locked the lever action. I was able to tap it out with a cleaning rod with no damage to the casing or rifle.
Looking in Wikipedia, it says that the 7.62X51 is the military version of the commercial .308 Winchester. I am completely confused.

NotSoFast
10-27-2009, 02:36 AM
I don't have any experience with that round personally, but I have spent time on other forums. Here is a link on The High Road forum that might help answer your questions. These fine people can probably help you a lot more than I can.

http://www.thehighroad.org/showthread.php?t=365079&highlight=7.62x51

Oblio13
10-27-2009, 08:18 AM
There's no practical difference between 7.62x51 and .308 Win. You should be able to use them interchangeably. You may have a rough chamber, and that would be my first suspicion. It may also be that the brass was very soft, or that it was coated with something.

NotSoFast
10-27-2009, 01:58 PM
This from that link I posted. There are slight differences.

7.62 NATO:
Bullet diameter 7.82 mm (0.308 in)
Neck diameter 8.58 mm (0.338 in)
Shoulder diameter 11.35 mm (0.447 in)
Base diameter 11.84 mm (0.466 in)
Rim diameter 11.94 mm (0.470 in)
Rim thickness 1.27 mm (0.050 in)
Case length 51.05 mm (2.010 in)
Overall length 69.85 mm (2.750 in)

.308 Winchester:
Bullet diameter 0.308 in (7.8 mm)
Neck diameter 0.343 in (8.7 mm)
Shoulder diameter 0.454 in (11.5 mm)
Base diameter 0.470 in (11.9 mm)
Rim diameter 0.473 in (12.0 mm)
Rim thickness 0.050 in (1.3 mm)
Case length 2.015 in (51.2 mm)
Overall length 2.800 in (71.1 mm)

I will say that the 7.72 does seem to look a tad smaller and should be a looser fit.

Oblio13
10-27-2009, 02:13 PM
.... There are slight differences.....


The specs are slightly different, but unlike the 5.56 and .223, it's not a practical difference. Shoot away with no worries.

ldsparamedic
10-27-2009, 04:12 PM
Thanks a bunch. I'll try it again and see what happens.

OzarksJohn
10-27-2009, 04:56 PM
Howdy.

I have heard of one other Savage 99 .308 behaving exactly as you described when used with surplus 7.62 NATO ammo. It's very likely either tight chambers or an out of spec batch of military ammo, either dimensionally or pressure wise. Are these brass cases or steel? As far as I know; all true NATO spec ammo should be brass cases and bear the NATO cross on the headstamp. Even then, it's made by everyone AND his dog. Military ammo never was as tightly controlled in specs as commercial ammo anyway, and the guns designed to fire 7.62 NATO were chambered with this in mind. A batch of military ammo might be just on the maximum tolerance limits spec-wise and be fine for a military gun. That might be just a bit too much for a tight chambered high quality Savage 99. Only match/sniper grade military rifles and ammo are held to the tighter standards that we tend to expect in commercial ammo and guns as a matter of course. With all the different "surplus" .308/7.62 out there, it's sometimes a crapshoot what you are getting. Also another .308 commercial rifle just might gobble up the stuff your 99 chokes on. I would proceed VERY cautiously. I love those 99's and I'd hate to see you beat yours up with a bargain batch of ammo.OzarksJohn

Mad_Professor
10-27-2009, 09:56 PM
I have a Savage model 99 in .308. I have a bunch of "military bulk" .308. I fired one round of the military in the Savage and the casing got stuck to the point it locked the lever action. I was able to tap it out with a cleaning rod with no damage to the casing or rifle.
Looking in Wikipedia, it says that the 7.62X51 is the military version of the commercial .308 Winchester. I am completely confused.

Look for signs of pressure (too much) in the case you removed: primer puckered up about the firing pin mark, a "ring" about the base of the case just above the case extractor groove. etc.

Next check case overall length with a set of calipers, if it exceeds the specified amount by much that will also cause a problem. From there check overall cartridge length in a few of the unfired rounds. They should to spec. for a reloading manual or below, some guns will tolerate longer depending in the chamber machining (where the grove/lands start) and action.

ldsparamedic
10-27-2009, 10:51 PM
It is brass. I will measure up the rounds before I fire any more rounds. I do not want to ruin a fire rifle.

Oblio13
10-27-2009, 11:12 PM
Have you inspected the chamber yet? Roughness in it is the most likely reason for a stuck brass case. A very thorough cleaning with a chamber brush is a good place to start.

Also, don't be tempted to lubricate either your chamber or cases. The brass needs to expand and grip the chamber walls instead of slamming back into the bolt face or allowing gas to blow by.

gunsmoke
10-28-2009, 05:29 AM
The Savage 99 has long been known to be very minimally (tightly ) Chambered. RCBS once offered ULTRA SMALL BASE DIES for handloading of .308, they still offer SMALL BASE DIES for your avg .308/7.62 auto loader.

The nest factor possible chamber roughness which is possible in later production 99s.

Lastly there is the ammo itself. There is great variation in production of 7.62 mil spec ammo for example HIRTENBERGER of Austria is known for two things extraordinary high ptrcision and the hottest 7.62 ever loaded. South African is also known as pretty warm stiff - in both cases the 7.62 was loade for dual use in FN MAG machine guns and FALs which have an adjustible gas system. The SA is pretty rough on the G#s which superceeded the FAL in SA service.

So uou could have any one or any combination of these factors.

Just a friendly suggestuin, if it turns out to be HIRTENBERGER production sell it for use in FALs and Galils, and buy yourself some equiv. PRIVI PARTIZAN. You should end up on the good end of such a deal HIRTENBERGER is sought out by FAL and GALIL shooters and sells at a premium. PRVI is first class Croatian manufacture and is much cheaper.

YOU SHOULD KNOW if your 99 is in giid shape and withing specs it is a VERY strong rifle and is probably well-capable of handling higher than SAMMI SPEC pressure ammo which HIRTENBERGER is.

Take care of that 99 it is a fine rifle and there is not likely to ever be any more produced. Savage sold all their tooling in the last 20 years to an Italian arms maker and it was so worn out the Italian maker scrapped it. It would be a VERY EXPENSIVE proposition to retool to manufacture it again and the market is relatively small too small for the required investment right now.

poacher
10-29-2009, 12:39 AM
Milspec ammo can tend to be a little thicker in the walls which could have caused your problems. You over all length may also be to blame. Lastly I would as others have stated here already look at your chamber and see if you have burring or somthing of that nature causing an issue. If none of these help I would suggest going to Midway, Powder valley or another reloading supply house and buying some brass to load.

Ya know once you roll your own loads you'll never look at commercial ammo the same way again. lol

Take care Be safe Poacher

www.handloadersbench.com

Pitdog
10-29-2009, 12:57 AM
Got one too. DO NOT fire the NATO spec ammo in it. Chamber is different, swelling of the cases are what is sticking the brass in the chamber. Stick with a quality handload, use commercial brass for this piece of history and don't punish it with the pressures the NATO ammo is producing.

150 Gr Speer SP
pushed by a charge of 37.5 grains of IMR 3031
Good standard primer
Should shoot just fine.

ArmySGT.
10-29-2009, 01:37 AM
I have a Savage model 99 in .308. I have a bunch of "military bulk" .308. I fired one round of the military in the Savage and the casing got stuck to the point it locked the lever action. I was able to tap it out with a cleaning rod with no damage to the casing or rifle.
Looking in Wikipedia, it says that the 7.62X51 is the military version of the commercial .308 Winchester. I am completely confused.

My friend had the same problem with his Savage 99. The answer don't use surplus 7.62x51. It is surplus for a reason. In his case the overall length was out of spec. The case was being mashed into the throat. This raised pressures to dangerous levels and meant a case stuck in the chamber.

ldsparamedic
10-29-2009, 02:03 AM
I went to my gunsmith today and he told me the military ammo is sized a bit differently and it was fire forming inside the chamber. He told me not to fire military ammo in unless I wanted to ruin the gun.

The rifle is in great condition. I just had it reblued as my father in law had it for a few years and I got back a rusted rifle. It was gone over after the rebluing and I was told it is in great shape. I would like to be able to pass down the rifle to my 6 year old when he is older. Pitdog, thank you for the reloading suggestion. My next purchase will be for a case of Starline 308 brass.

Thank you to everyone who gave me suggestions/hints with this problem.

Oblio13
10-29-2009, 09:52 AM
What kind of military ammo was this? NATO in a SAAMI barrel shouldn't be a problem. The other way around may or may not be, depending on how hot the load is.

(NATO 5.56, on the other hand, is essentially loaded like SAAMI .223 proof-loads.)

All brass fire-forms in the chamber, it's supposed to. It creates a seal to prevent gases from flowing back.

Mr.B
10-29-2009, 11:20 PM
I use to fire commercial .308 out of my Lee-Enfield INDIAN Rifle Model: 2A1, I was told I shouldnt from some guys at the range that are into surplus rifles, I did have a problem with split casings, so now adays its just NATO 7.62x51.

Artical below covers the rifle plus the .308 vs. NATO 7.62x51


http://www.surplusrifle.com/shooting2006/762ishy/index.asp

-B

Oblio13
10-30-2009, 08:18 AM
The article cited in the link above is misleading. The pressures for SAAMI .308 and NATO 7.62 are measured in different ways. If measured in the same way, commercial (SAAMI) pressures are higher than NATO, not the other way around. Here are the numbers:

NATO 7.62 is loaded to maximum average pressure 50,000 CUP, which translates to approximately 58,000 PSI. It is proofed at 67,000 PSI.

SAAMI .308 has a maximum pressure of 62,000 PSI. (Most ammo is loaded to about 55,000 - 57,000 PSI because companies worry about lawsuits, but 62,000 PSI is the industry established maximum.) The proof cartridge pressure is 83,000 to 89,000 PSI.


As for chamber dimensions:


From Walt Kuleck:


They are not the same.

They are the same.

They are not the same, 'cause the .308 Win was released by Winchester several years before the Army standarized the T64E3 as the 7.62MM. You'll get an endless discussion of pressure specs, endless because SAAMI and the Ordnance Dep't measured pressure in different, unrelateable ways. However, the chamber drawings are different.

They are the same, 'cause nobody makes 7.62MM ammo that isn't to the .308 "headspace" dimension spec. So 7.62MM ammo fits nicely into .308 chambers, as a rule.

Most of the time it's a distinction without a difference. But if you intend to shoot .308 commercial in a military arm chambered for 7.62MM, first check the headspace with .308 commercial gauges first.


From Clint McKee:

If you have a chamber with headspace much in excess of 1.636 (say, 1.638, SAAMI field reject), you must use only U.S. or NATO Mil Spec Ammo (always marked 7.62mm & with a cross enclosed by a circle) since the NATO mil spec calls for a far more "robust" brass case than often found in commercial (read .308 Winchester) cartridges...

I have measured many, many types/manufacturers of commercial and NATO ammo ... If anything, I have found various Nato ammo to be in much tighter headspace/chamber compliance than commercial ammo. .. I.e., if anything, NATO ammo seems to hold at the minimum SAAMI cartridge headspace of 1.629-1.630, better than some commercial ammo!...


Bottom line: NATO 7.62 pressures and case dimensions shouldn't be a problem in a commercial (SAAMI) .308 barrel. (Confusingly, it's the other way around for 5.56/.223) If it is, there's something weird going on. What kind of military ammo was this?

yardburd
11-06-2009, 11:28 PM
I had the same problem with my 300WM Savage. I ended up cracking the bolt handle in my effort to clear the round. I found that the problem went away when I started loading to a little below the maximum and using a neck-sizing die. I also think, but cannot prove, that the finish in the chamber of the Savage may be less than perfect. I made a lapping tool out of a spent round and used it to polish the chamber.

Pitdog
11-08-2009, 01:49 PM
Dimensionally the cases SHOULD be the same, but the difference in the 7.62 chamber VS the .308 chamber is in the angle of the throat and the amount of freebore. If that 99 in .308 is chambered like mine, and probably like Sarge's Friend's, the rifling comes back to the neck of the chamber and has NO freebore and a short throat. This will allow the very tiniest stretch of the case neck into the chamber stick. Militay 7.62 brass is sought after by reloaders because it IS thicker because of the decreased internal dimensions, making it last longer, as well as the fact it is harder brass than commercial, so that it has less tendency to separate in a hot dirty machine gun barrel. Commercial brass is softer and thinner which means while it does exapand to the chamber, it also contracts allowing for less effort in extraction, especially in commercial chambers.
Were there a burr in the chamber, it would have been a problem from round one of whatever ammo, and would have been dealt with before now unless it was somehow damaged by a poor cleaning method which is unlikely. It could be perhaps dirty, and there is always the possibility it was allowed to rust, and or was pitted, which will make cases difficult to extract. However if the problem is NOT there with commercial ammo or brass, then it is obviously the mil spec ammo.

Michael32170
11-09-2009, 04:06 PM
I have a Savage model 99 in .308. I have a bunch of "military bulk" .308. I fired one round of the military in the Savage and the casing got stuck to the point it locked the lever action. I was able to tap it out with a cleaning rod with no damage to the casing or rifle.
Looking in Wikipedia, it says that the 7.62X51 is the military version of the commercial .308 Winchester. I am completely confused.

If you talk to manufactures, you will get two inputs. From the manufactures that design for the 308, they say 7.62 X 51 will not cycle well and will create more wear in the rifle. The Springfield Armory says not to use 308 in their M1A to avoid "slam fires".

Springfield says that sometimes the bolt slamming back into the bullet will sometimes set off the .308 round.

There are several differences in the two cartfidges, including case thichness and material hardness.


http://www.dsarms.com/ammowarn.asp


http://www.springfield-armory.com/armory.php

Pg 4

Tim Horton
11-12-2009, 03:50 PM
My thoughts on this are to only use commercial brass in the rifle.
Be they factory loaded, or reloaded.
Now, if you want. You can reload full metal jacket bullets in
commercial brass, to use for minimal pelt damage etc.
But there is maybe too much tollerance in manufacturing
millitary ammo for the old Savage to handle.

Of course my oppinion and $1.oo will get you a cup of coffee----
somewhere.

Good luck
Wyo

Pitdog
11-14-2009, 11:16 AM
I know where .49 cents and your opion on firearms can get you an unlimited refill cup of coffee and some interesting conversation!

Love that old 99, getting it ready to go over to the Old Man, it was his brother's and he wants to use it while he can.

jim
11-14-2009, 10:59 PM
Good for you Pit. Will he be using it this deer season? Hope so.

jim

cmdan
11-16-2009, 06:09 PM
I was raised in a family of hunters and have always been told, the military 7.62 will not work in a modern hunting rifle, but I never asked why. This thread answers the why. I am guessing the 7.62 will work for some who shoot....say a civilian AR10, which shoots a .308 bullet. Anyone know for sure?

Pitdog
11-17-2009, 09:16 PM
Yeah Jim, he is going to hunt with it, got him some lighter loads put together for it, and am putting a scope on it so he can see.
The AR 10 will eat about anything you feed it, however depending on how well polished the feed ramps are, the soft point hunting commercial hunting ammo can cause jams. It may not shoot quite as well, as the bullet will be farther off the lands, but bullet diameter is EXACTLY the same so the commercial may shoot just as well as anything, but it will eat the FMJ 7.62x 51 with no problems.

vgodenwa
06-26-2010, 11:21 PM
Don't shoot any ammo in any gun that doesn't like it.
Locking up the action is a sign of extreme pressure.
The cause would be nice to know, but doesn't change the fact you can't shoot that ammo in that gun.
7.62 Nato is fairly mild in American loadings because a M1A needs it that way. But foreign ammo quality control differs.
5.56 Nato is hot and requires a longer throat to compensate.
You have a collectible rifle - treat it to some good commercial ammo.
That stuff you have could be de-linked machine gun ammo loaded hot to run in a dirty gun - regardless of Nato standards.
All of this is more or less stated above. I just tried to condense it.

Von

Tim Horton
06-29-2010, 01:18 PM
I've read a dozen articles about 308 vs 7.62 nato.

About 1/2 said they were the same, the other 6 said different.
About 1/2 said shoot and don't worry, the other 6 said don't shoot.

What I have experienced leads me to believe this.

Military ammo has looser manufacturing tolerances to speed production.
The military chamber is big enough to fire any ammo under severe conditions.
If it doesn't someones skin is in trouble.

Commercial / sporting chambers and ammo are produced with tighter manufacturing
tolerances. You can see where this is leading.

The military doesn't load ammo hotter. They want there equipment to last.
Commercial ammo is loaded to make soft point bullets to perform correctly.

That's about my 2 cents worth of knowledge.

Good luck
Wyo

Pitdog
07-01-2010, 08:34 PM
The fact to remember is that 7.62 brass DOES have thicker walls. Reloads need to be reduced by 10% if you are looking @ .308 Win data, commercial brass has more case capacity.
Having looked @ the prints for both cartridges there is a difference, I will try to get woman to scan the prints and I'll post them and try to point it all out. I'm computeratorially stupid.

ldsparamedic
07-05-2010, 05:41 PM
Thank you all for the info and suggestions. Pitdog, I look forward to seeing the scans.

ldsparamedic
07-06-2010, 02:59 PM
Let me throw this out. I am looking at buying an M1A. Springfield's website cautions against reloading due to slam fires due to non military primers. If I reloaded new .308 brass with military primers, would the Savage be able to handle the reloads or will I be beating my rifle?

Pitdog
07-07-2010, 02:18 AM
The cup is harder on the primers, we use CCI @ work to prevent them slam firing from floating firing pins, and they also make a 7.62 Primer, specifically for reloading for M1A and Garands, the cup is yet a little harder. I would hesitate to stuff them into my Savage, load up two differernt loads, and know it is possible to interchange if necessary. But don't unless vital.

MEBrian
07-07-2010, 02:22 PM
I've put a large amount of .30/06 rounds loaded with Winchester primers through my Garands- no problems.

glocker21
07-12-2010, 08:23 PM
The cup is harder on the primers, we use CCI @ work to prevent them slam firing from floating firing pins, and they also make a 7.62 Primer, specifically for reloading for M1A and Garands, the cup is yet a little harder. I would hesitate to stuff them into my Savage, load up two differernt loads, and know it is possible to interchange if necessary. But don't unless vital.

CCI #34 are the military primers and are available for civilian purchase. I have been using CCI #34 and the CCI Large Rifle virtually interchangebly and have seen zero problems with all three of my M1As. I have had exactly one slap fire and that was with remington primers

Michael32170
08-06-2010, 10:35 AM
I was raised in a family of hunters and have always been told, the military 7.62 will not work in a modern hunting rifle, but I never asked why. This thread answers the why. I am guessing the 7.62 will work for some who shoot....say a civilian AR10, which shoots a .308 bullet. Anyone know for sure?

Ask the manufacturer, they will be happy to help you. I think most rifles can handle both.

woodsman
08-07-2010, 04:28 AM
I had this problem a few years back with my m1A using that south African surplus .308 that was everywhere back then. 1 out of about every 200 would get stuck. I have never had this problem with any other ammo. I shot it all before I took the time to measure some cases, but i assume some were just a little off.