7.62 x 51 load data...


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uneasy_rider
September 16, 2007, 07:06 PM
I am looking for some good service load data for 7.62 x 51. The books all give 308 winchester data. What are some good loads for an M1A and FAL? I am trying to recreate military ammo specs. I have Varget and Winchester 748 on hand.

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USSR
September 16, 2007, 07:14 PM
The data is interchangeable, just restrict yourself to the bullet weights and powders that are suitable for your M1A (ie. bullets < 180gr and powders no slower than what you've got now).

Don

Bad Flynch
September 16, 2007, 08:23 PM
Many times, loading data quoted for the 7.62 x 51mm NATO cartridge assumes military cases. Military cases have a little less case capacity that do typical commercial .308 Win cases, especially Winchester or Federal.

Be sure to note the type of case the book quotes as being used. Loads for commercial cases might be a tad warm for military cases.

uneasy_rider
September 16, 2007, 08:34 PM
Where can I find specific load data for 7.62x51 that takes into account military cases?

USSR
September 16, 2007, 09:17 PM
Where can I find specific load data for 7.62x51 that takes into account military cases?

Don't know. Simply reduce any loads from load books using commercial brass by 1.5 grains.

Don

Sunray
September 16, 2007, 09:41 PM
Just use .308 Win data and reduce by 10% for milsurp brass. Milsurp brass is a wee bit thicker, so it has a slightly lower case capacity. The .308/7.62 loves 165 grain hunting bullets and 168 or 175 grain match bullets with IMR4064 and regular large rifle primers. 168's for distances up to 600 yards, 175's past there. Varget or 748 will do though.
"...recreate military ammo specs..." Why? Milsurp ammo isn't made for great accuracy. NATO ball uses a 147 grain FMJ bullet. If you insist on milspec velocities, work up a load using 150 grain bullets. You have to work up a load for each rifle. No two rifles will shoot the same ammo the same way.

GunTech
September 16, 2007, 10:03 PM
Many loading manual have listing for service rifle. For example, the 7th edition Hornady manual has sections for servce rifle for 308, 30-06 and 223, IIRC.

The standard match round for the M1A and similar rifles is 168gn SMK over 41.5gn H4895 in LC cases.

Here's a bit on duplicating M80 that was passed on to me. You can buy WC846 pull down powder for about $100 for 8 pounds.

Mil spec for M59 Ball:

Bullet: 150.5 grain FMJ
Powder: 46 grains WC846 or 41 grains IMR 4475
Velocity = 2750 +/- 30 fps @ 78 ft.
Pressure = 50,000 psi max average.
Accuracy = Carton or clip pack - 5" mean radius @ 600 yards.

Mil spec for M80 Ball:

Bullet: 149 grain FMJ
Powder: 46 grains WC846, 41 grains IMR 4475, or 41.5 grains IMR 8138
Velocity = 2750 +/- 30 fps @ 78 ft.
Pressure = 50,000 psi max average.
Accuracy = Carton or clip pack - 5" mean radius @ 600 yards, link pack - 7.52" mean radius, max average at 600 yards.

For use in overhead fire applications the lot of M80 Ball also had to meet the above accuracy requirement with an additional requirement of no more than a 25" maximum extreme spread per target at 600 yards.

Mil spec for M118 Special Ball / Match

Bullet: 175 grain FMJ
Powder: 44 grains WC846 or 42 grains IMR 4895
Velocity = 2550 +/- 30 fps @ 78 ft.
Pressure = 50,000 psi max average.
Accuracy = Carton - 3.5" mean radius @ 600 yards

Mil spec for M852 Match

Bullet: 168 hollow point boat tail
Powder: 42 grains IMR 4895
Velocity = 2550 +/- 30 fps @ 78 ft.
Pressure = 50,000 psi max average.
Accuracy = Carton - 3.5" mean radius @ 600 yards

BLC-2 is the commercial equivalent of WC846. In the manufacture of a spheroidal ball powder like BLC-2 or WC846 the powder is manufacturered (in the past often from reclaimed/recycled cannon powder) and is then tested and sorted by grain size, burn characteristics, etc, to produce a particular lot of powder with the required/desired burn characteristics. The technician doing the mixing can also essentially custom mix a powder to comply with a customers specific requirements. This ability to easily mix and customize spheroidal ball powders is where the (entirely correct) idea develops that commercial powder manufacturers do not use the same "cannister" grade powders that are sold to reloaders by the pound or keg. They order a powder having certain specifications and the lot is custom made to those specs.

However, many of the commerical powders that are available to reloaders are essentially made to military specifications as is the case with WC846/BLC-2 and WC844/H335 and IMR 4895, which is of course IMR 4895 with the IMR standing for "Improved Military Rifle". However as with any powder from a given lot there is always some variation within the specification from lot to lot so you will want to start a bit under the starting load and then load up to the velocity desired. As a result the final charge actually used may be slightly higher or lower than the charge specified. It is the velocity and pressure that count, not the actual charge weight used. In short, the actual charge specified is of only general ball park use.

In addition, many military powders are available as either new surplus or as pull down powders. I am comfortable with new surplus powders, but the pull down powders make me a little nervous. You can take a large lot of powder and assuming it is well mixed, you can load it into several thousand rounds of ammuiiton and get reliable and predictable results. However, you can't neccesarily go the other way and pull the powder from several thousand rounds of ammunition made from several to several dozen different lots of powder made perhaps decades apart and then mix them together and expect the same consistent results. You are at best relying on having a (hopefully) large and (hopefully) random sample of powder from many different lots that you hope in the end will average out in terms of burn rate and consequently produce a powder lot with burn rates within the WC846 specification. That's a lot of hoping. On the other hand if the pull down powder is all from the same lot of ammunition all of which was made from the same lot of powder, you are good to go - but I have yet to find a pull down surplus powder supplier who can assure me of that.

In any event whether you use new or pull down surplus WC846, commercial BLC-2 or surplus or commercal IMR 4895, if you are creating an M59, M80, M118 or M852 clone, start 10% under the given loads and work your way up to the specified velocity incrementally while carefully monitoring for signs of excess pressure as all of the specified loads are fairly hot loads by most reloading standards.

SlamFire1
September 16, 2007, 10:18 PM
4895 is the standard powder for a M1 or M1a. Any of the brands, H4895, IMR, or AA should be the first powder to try, and if your rifle will not function or shoot well with that series of powder, you have a rifle problem. If I were to start over, I personally would start using H4895 as I have heard it is a shorter stick powder than IMR. But all of my loads since the early 90's have been with IMR 4895.

I shot about 24 pounds of AA2495 and found my lots to give charge velocities identical (for all practical purposes) with IMR 4895. The stuff shot well and cost less at the time. Depending on the 308 barrel, with a 168 Sierra or 168 Nosler Match, an excellent load will be between 40.5 and 41.5 grains.
For my rifles, when the barrel is new, I get the velocities with the accuracy I want at the 40.5 grain level. After the first couple thousand rounds, I bumb up the charge, depending on what the chronograph tells me.


I have attached data fired from a 24 Douglas barrel. The average with a 41.0 grain load is just a little above 2550 fps, and this was an excellent load in my newly rebarreled M1a. I recommend testing your loads with a chronograph and keep the velocity average between 2550 and 2600 fps.

168 Nosler 41.0 AA2495 Lot 21594 CCI#34 LC Mixed OAL 2.8
T = 82 F
Ave Vel =2567
Std Dev =7
ES 19
Low 2556
High 2575
N = 7

I never loaded 150s in the M1a, but I would think keeping them around 2650 fps would produce an accurate load that would not be hard on the rifle. Dont attempt to duplicate the velocities of some of the surplus ammunition on the market, some of that stuff is way too hot. I tested some Chinese and CAVIM surplus. The CAVIM was over 2900 fps with a 150, the Chinese about 2800 fps. That stuff was way too hot, and was not very accurate either.

There should be an barely perceptible clip clop to your rifle when the loads are right. When the event is simply a huge bang and the rifle has cycled without you "feeling" it, your load is probably too hot.

I tested Varget in one of my match M1a's and got case head seperations. That tells me Varget is a bit slow, unlocks the action when breech pressure is too high, and therefore will be marginal in some rifles. Like mine. Which is too bad because Varget shot excellent groups in my bolt rifle.

W.E.G.
September 16, 2007, 10:50 PM
41.5 grains IMR 4895 with a Sierra 168 MatchKing

GunTech
September 16, 2007, 10:53 PM
Great post Slamfire,

I've had great success with H4895, and Vihtavuori N135 is even nicer - almost identical with 4895, with lower SD and much, much cleaner. I've got to WW cases, which hold up quite well, and have a case volume around 38 grains of water, makeing for lower pressure at the same velocity. WW is also pretty consistent, and even weighing and sorting it comes out cheaper than Lapua.

I haven't tried AA 2495, but will put that on the list. I've been shooting a lot of ball powder lately, because I'm lazy and it meters so nice in my Harrell. 2520 mostly, with a little W748 and even BL-C(2) for plinking ammo.

GunTech
September 16, 2007, 10:58 PM
Uneasy_rider brings up a good point. 7.62x51mm is not 308. The PMax for NATO is only 55,000 psi versus 60,000+ for 308. In particular, rifles like the FAL do much better with bullets in the 150gn range and moderate pressures. Your best bet is to duplicate the rounds these rifle were designed for, and not hot rod them. They don't have the strength of bolt guns.

When I use heavy bullets in my M1A, I use a NM groved piston. The AMTU reported that heavy bullets used in the M14 can lead to early unlock in some rifles, causing an unsafe condition. Stick to bullet weights of 175 gns and under.

GunTech
September 16, 2007, 10:59 PM
Here's a great article by Glen Zedicker on match reloading for the M14. Worth a read. It's free.

http://www.zediker.com/downloads/m14.html

Ian Sean
September 17, 2007, 01:42 AM
My personal favorite load for my FAL's, Cetme and 1919 (belt fed semi).

Cycles the weapons fine, no problems and decent accuracy for what I consider my "plinking' load.

Most books quote 44grs. as a "start" for Varget, I started a little lower and worked up to the 44.

I have settled on 44 grains of Varget pushing a 147 gr FMJBT in LC brass, I also have been using the same load in a ton of Indian (OFV) brass with good results also. Used CCI primers and Federals with no issue.

Recently made up some pushing 150 gr (Hornady) FMJBT's, ran 50 or so each through my Cetme and one of the FAL's ....all went well, but my CETME really liked this load, very good accuracy out to roughly 100-150 yards knocking down bowling pins, I honest to god suprised myself with how well it/I shot.:)

Once I use up my Varget loads, I am going to give 4895 a shot.

SlamFire1
September 17, 2007, 09:49 PM
I haven't tried AA 2495, but will put that on the list. I've been shooting a lot of ball powder lately, because I'm lazy and it meters so nice in my Harrell. 2520 mostly, with a little W748 and even BL-C(2) for plinking ammo.

Accurate Arms really blew it when the named their powder AA2495. I called them and they told me they mixed the stuff to have an identical pressure curve with IMR 4895. I suspect they were being "cute" when they named it 2495, as it was half the price of 4895. Not any more!

Because of the name, no one knows what the heck the stuff is. Funny too, the 24 pounds that I used, which was just excellent stuff, lot 21594, was made in China of all places. It gave me just outstanding consistency in the 308, 30-06 and .223. Wish I had bought a boat load.

AA2520 was "the" M1a powder for a couple of years. Because it is a ball powder people just loved the throw consistency. Hardly anyone uses it anymore, probably because of lot to lot variance. Accurate Arms buys powder from any Tom, Dick, or Harry, and each lot has to be tested to develop loads. I think that is what happened to 2520. Might also be because it leaves a lot of soot in the gas system. Almost like charcoal dust. Still it shoots great in the .223, 308, and 30-06.

I am shooting my 80's vintage AA2520 in the off season. Mostly in AR's. When I pull that bolt apart to clean, it is just covered in soot. Still shoots cleans with decent X counts at 300 yards.

I called Vihtavuori about what to use in a M1a and was referred to an "expert". After talking with him, I found out he was a competitive highpower shooter with lots of experience, so I trusted his recommendations. He did not like N-135 in the M1a. claimed it beat up the rifles. OK. He recommended N-140 instead.

If you were into shooting Highpower, in the middle nineties N-135 was the hot powder in the .223. The AMU had a "V-8" load at 600 yards, and that powder was what all the Camp Followers were using. Now, no one is using the stuff.

I tested N-140 in the 308 and .223 and decided it was a good powder. I have used it in the .223 Service rifle, and 23.5 grains with a 80 Sierra, Winchester brass, and CCI-41's is my 600 yard load. It is good enough that this year at Perry my lowest long range score was a 197. I have yet to shoot 200 at long range at Perry. Always some blasted wind or rain squall.

GunTech
September 17, 2007, 11:16 PM
More good info Slamfire,

Vihtavuori lists the burning rate of N135 right between H4895 and IMR 4895. I've been using it for many years without issue.

Dave R
September 17, 2007, 11:43 PM
Where can I find specific load data for 7.62x51 that takes into account military cases? Speer No. 13 manual "stars" some load as as being appropriate for gas-operated military semis. That's as close as I've seen to what you're looking for.

Ditchtiger
September 18, 2007, 01:05 AM
Find- Loadbooks USA, Inc P.O. Box 129, Acton, CA. 93510
Ph. No. 1-661-269-8991
The Complete Reloading Manual for the .308 Winchester

has 85 pages of only .308 data
several pages on using mil.surp. cases
2,788 proven & tested loads
148 various bullet designs
63 different powders
It's only $7 !!!!!!!!!!!!

Ditchtiger
September 18, 2007, 01:34 AM
Find- Loadbooks USA, Inc P.O. Box 129, Acton, CA. 93510
Ph. No. 1-661-269-8991
The Complete Reloading Manual for the .308 Winchester

has 85 pages of only .308 data
several pages on using mil.surp. cases
2,788 proven & tested loads
148 various bullet designs
63 different powders
It's only $7 !!!!!!!!!!!!

KI.W.
September 18, 2007, 03:50 PM
There are old Lapua no military cases 7,62x51. They are maby best ones .308 You can find.

Wild Deuce
February 17, 2008, 01:01 AM
Wow! I feel out of my league.

I'm not a complete novice but I'm still fairly new in the rifle game. I couldn't think of a better place to ask this so I thought this would be the best thread to resurrect. This is not a reloading question (all the ammunition mentioned below is factory loaded) but I can't think of a better qualified demographic than reloaders.

Based on what I have read so far ....

1. I should not be using my Black Hills 168 Grain .308 Win ammunition in my SA SOCOM II rifle. Instead, save this ammunition for my Savage Arms 10FP-LE.

2. I should be using my Winchester White Box 147 Grain 7.62 ammunition (NOT .308 Win) in the SA SOCOM II rifle. It is also safe to use this Winchester 7.62 ammunition in the Savage Arms rifle.

Are these assumptions correct?

Further inquiry .... Is there a difference in the primer hardness between the Black Hills ammunition and the Winchester ammunition? Which ammunition is loaded hotter? I plan on reloading at some point. Should I sort my brass by type only (.308 Win vs. 7.62) or should I also sort by rifle used?

Thanks in advance.

Wild Deuce
February 17, 2008, 12:15 PM
I kept looking and may have found an answer to some of my questions here ....

http://www.thehighroad.org/showthread.php?t=335419

If anyone has anything to add, it would be appreciated.
Thanks

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