.308 reloading question

[7.62X51]

I know this should probably be in "ammunition" but that area has so little traffic compared to this. Anyway, just inherited a bunch of RCBS reloading gear from my twin brother, so I'm getting into it whole hog, a question: is a 7.62X51 for these FAL's any different to the .308 in the reloaders manual? (I cant find anything for 7.62X51 NATO) And also the same question for .223 Remington, is it different that 5.56X45 NATO or do I just use the same specs as .308/.223? Thanks for your time and any other snags I should be looking out for, let me know too. http://www.fnfal.com/forums/smile.gif

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Invest in premium metals, "brass, led and copper"

[rMac71]

7.62x51 and .308 are essentially identical as well as the .223 and 5.56 X 45. There are some technical aspects to reloading gas cycled actions. They tend to do a little better with powders toward the faster end of the burning scale. I use AA230C in my FAL with good results. If you can find them I would suggest cci #34 primers as they are made to mil-spec for autos and have a little harder pan which helps prevent slam fires. Also, you want to use bullets with a cannelure and crimp them to prevent bullet movement under recoil and feeding. Hope this helps.
Randy

[EMDII]

They are different, primarily in pressure and NOGO headspace.

NATO spec 147 grain 7.62x51mm is at 50,000 psi.

.308 Winchester specs go as high as 58,000 cup.

LOTS of discussion on different measuring systems. I would load to a 2750 fps MV on 150 grain stuff, and load to peak pressures < 51,000 on other loads.

Even IF you can control felt recoil using gas adjustment, your barrel still sees the pressures you generate using .308 Win loads.

Caveat Emptor.

PS- yes, it's going to Ammo.
AND- MilSpec proof loads go 68,000 psi. Each barrel passes a proof load at least once in its life.

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1*.....Train Like You Fight: Second Place is NOT an Option.

E.M. (Ted) Dannemiller II

[W.E.G.]

Put on your thinking cap and bring out the wet-vac (in case your brain explodes), and read the discussion at http://www.fnfal.com/forums/Forum13/HTML/000187.html

[W.E.G.]

And ripped-off from Dano's post

http://albums.photopoint.com/j/View?u=973743&a=7145445&p=28118463&Sequence=0

at http://www.fnfal.com/forums/Forum13/HTML/000020.html

[sixplusone]

[ September 04, 2001: Message edited by: sixplusone ]

[rMac71]

Thanks for the heads up on the cci34's. I have thought about trying mag primers as they are supposed to have a harder pan. As far as the 7.62 X 51 and .308 being different. Well, yeah technically, but I use .308 dies and .308 data. Just start on the low end and work up. Pay attention to the posted pressure figures in the data manual and keep it under 51K. I also headspace my FAL's with a .308 go, field and no-go gauge. So far I haven't had any problems. As far as the faster burning powder, I should have said faster burning in the .308 range. I have done extensive testing with various .308 powders and have found that powders in the range of BLC-2, AA2230C, AA2495 seem to dump less pressure into the gas system and produce less bolt/ carrier velocity and are easier on the rifle overall. As far as accuracy, I have had the best results with 147gr FN Boattail bullets with 43 gr AA2230. This produces 1.5 - 2 inch groups out of my rifle at 100 meters. I also have good success with 150 gr. Hornady sst and IMR 4064. This is a good hunting load and has produced a few 1 inch groups with my rifle at 100 meters.
Randy

[TideWater 41009]

gary.jeter's post of the military spec's brings up a question. Almost every time sombody shoots some military ammo and posts a chronograph reading that is faster than whatever the percieved standard is thought to be, or they say they think the ammo seems "hot", somebody will respond by saying that it must be machine gun ammo, implying or explicitly stating that machine gun ammo is loaded to higher pressure or velocity. Yet the info from this technical page states under "Use" that it is for machine guns and rifles, and I assume the ammo meets NATO spec's.

My question then; does anyone know of any factual evidence that verifies the claim that "machine gun" ammo is "hotter" than standard NATO ammo, or is this yet another internet rumor that will not die?


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"A man not shackled with the truth can win any debate."

[MIKE14]

This is a problem to look out for. Most dies
resize to work in all rifles of that caliber.
I was having serious failure to extract problems in my NM barrled M1A. I had to switch to a set of RCBS small base dies to overcome this problem. The small base dies are designed to work with Semi and full auto gas operated guns. I'm new to FN-FAL's so I can't coment on if the SB dies are necessary for the FAL. Just my .02

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M-14 OUT

[Tom S]

My SPEER reloading manual does list seperate data for "7.62 Nato" using military brass. But I believe they list diferent data from "308 Winchester" loads only because the case walls of the military brass is usually thicker than commercial brass-giving less internal volume. Load em up, and shoot em!!!

[sixplusone]

On this topic, the Hodgdon site has some interesting comparisons for tempurature effects on powders and pressures. Of couse they're selling the temp. resistant powders,ie EXTREME brand. This might come into play if you heat a Bbl. with a 20rd mag then pause with a round in the chamber. Higher pressure will be there when it is finally touched off. Comments?

Also are these steel core brass plated bullets any worry in bbls.?

[Tom S]

If there is a true "expert" out there-please correct me if I am wrong. Many folks seem to be so worried about shooting "steel core" bullets thru their barrels, why? The core of the bullet(either steel, lead or whatever)does not contact the barrel rifling, it is the copper jacket that is forced against the lands as the bullet moves down the barrel?
I don't see how it matters what the core of the bullet is made of as it refers to barrel life? Feedback?.......

[rMac71]

On the issue of small base dies -- my FAL does not need them but I have a friend with an M1A and his gun will not cycle my handloads reliable. They are a little tight in his gun. So, some very well might require SB dies. I do adjust my FL resizer die to my rifle chamber so they don't overwork the brass. I think you would just have to try and see. Someone out there makes a cartridge headspace guage that you can use to measure fired case headspace and then adjust your die. I believe it is Stoney Point. I use this item to adjust my dies and it is great. On the issue of steel core bullets, if they have a copper jacket as opposed to copper washed, they should be ok. I would be conservative in using copper washed bullets, but I think they use a very mild grade of steel and shouldn't hurt the barrel to much.
Randy

[Upside Down @ 100 MPH]

Hey 7.62,

I use the .308 Win. data in commercial brass in my STG58 and so far no problems.

Miltary brass like Lake City, has less case capacity and will have somewhat higher chamber pressures than the same load in a commercial case. I have a Hogdon manual that lists loads for miltary brass as well as commercial brass. I'm not sure if I would even attempt to load mil. brass except for Lake City, which is U.S. manufacture.

I have an RCBS X die (not a small base) that sizes my cases enough to feed reliably in my gun. Your mileage may vary on this. I haven't compared headspace between a fired and resized case yet but will soon. I may be oversizing mine.

Stoney point and RCBS sell tools to check the "shoulder to base length" so that you can size the brass to a certain dimension. I like .004" less length on a sized case than a fired one in an autoloader. I use the Redding shellholder set that has different thickness shellholders to accomplish this and it is repeatable for me. My rifle just closes on a 1.632" headspace gauge which is .002" longer than a "go" .308 Win. and about .0005" longer than a "go" 7.62 Nato gauge from my info source. I haven't fired any mil. surplus ammo but it should chamber with no problems.

I haven't had any problem so far with bullet setback from not having a cannelure and crimp. Some of the bullets I have used have them and some don't, but I have seated all of my bullets longer to get the bullet closer to the rifling, about .020" away in my case, so a cannelure is useless in that instance because the bullet isn't seated deep enough to use it. My gun is more accurate with the bullet closer to the rifling.

I have also "found" some accuracy by checking case runout after resizing and bullet runout on a loaded round. My RCBS sizing die and Redding seating die produce loaded ammo that usually has .002" or less runout. Some rounds just won't make it because of case wall thickness variations. These I use for plinking.

Reloading is fun if you like to tinker, but it is dangerous, so "Do your due diligence".

My .02,

Greg

[This message has been edited by Upside Down @ 100 MPH (edited March 24, 2001).]

[MIKE14]

Hey Upside Down: I've been thinking about buying the Redding micrometer seating die.
How much variance do you get in OAL?
I also like the Idea of Redding's precision
shell holder are they worth having?


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M-14 OUT

[This message has been edited by MIKE14 (edited March 25, 2001).]

[Dano]

Both the Redding Competition Bullet Seater and shell holders are worth the expense.

You will gain more flexibility and control of handloads with these tools

The bullet seater will allow you to seat bullets with .001" accuracy.

The shell holders will give you precise control of cartridge headspace.

Money well spent!

[Upside Down @ 100 MPH]

Ditto to Dano's remarks, spend the money and get the good stuff. I also have the Redding "S" sizing die that uses a bushing to size the neck but haven't used it yet because I still have to order the correct bushing for it. When set up properly it's supposed to work the neck less and increase case life.

The Redding seating die is great. It has a micrometer adjustment graduated in .001" increments. The important measurement for checking length on a loaded round is from the base to the ogive of the bullet. I have a Stoney Point tool that fits onto a pair of dial calipers that does this. When all of the rounds are the same length from base to ogive, there will be a slight variation in overall length(base to tip of bullet). Don't worry about that. It's the base to ogive measurement that counts.

Get a concentricity gauge to check runout on your cases and loaded rounds.

Forster is another company that makes quality reloading gear, dies, etc.

Greg

[Aifwikir]

Refinish Guy:
["My question then; does anyone know of any factual evidence that verifies the claim that "machine gun" ammo is "hotter" than standard NATO ammo, or is this yet another internet rumor that will not die?"]

This is a RUMOR that will not die! There's no such thing as 7.62 machinegun ammo. 7.62 NATO is 7.62NATO. The only exception to this is the 7.62mm Match Grade. Match ammo isn't mark "Nato".
Take care
Aif


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I don't SUFFER from insanity,,,,
I ENJOY IT!!

[This message has been edited by Aifwikir (edited March 25, 2001).]

[rMac71]

Machine gun ammo being hotter? Sounds like another urban legend to me.
Randy

[Mr pogo]

Dont know if the MG 7.62 is hotter or not, if not may have derived from the hot 9mm subgun ammo some of the Nato countries have.

[TideWater 41009]

Originally posted by 7.62X51:
...a question: is a 7.62X51 for these FAL's any different to the .308 in the reloaders manual? (I cant find anything for 7.62X51 NATO) And also the same question for .223 Remington, is it different that 5.56X45 NATO or do I just use the same specs as .308/.223? Thanks for your time and any other snags I should be looking out for, let me know too. http://www.fnfal.com/forums/smile.gif


I dug through my stack of loading manuals and noticed that the 1979 Speer Reloading Manual and the 1986 NRA Handloading Manual list loads for what they called the ".223 Remington (5.56 mm)" and ".308 Winchester (7.62 mm NATO)". The 47th Lyman Reloading Manual lists loads for the ".308 Winchester" with the words "7.62 NATO" in smaller letters.

The NRA manual states, "The principal complication in handloading for the .308 Winchester is that there is a great difference in capacity of the various commercial and military cases. Winchester-Western commercial cases are usually lightest of all, weighing only about 155 grains, and consequently these have the greatest powder capacity. Military cases are designed for use in a variety of automatic weapons, some of which do not function well (if at all) with light thin-walled cartridge cases. The military cases are therefore made with thicker walls and head, and usually weigh about 180 grains...which has a very significant effect on the interior ballistics of the loads. The NRA found that a full-charge load developed in Winchester-Western commercial cases increased by as much as 12,000 c.u.p. in chamber pressure when assembled in Lake City military cases, with no other change in components. To avoid problems due to differences in case capacity, it is necessary to reduce the powder charge when changing from cases of greater capacity to cases of less capacity. A satisfactory rule of thumb is to decrease the charge weight in the heavier cases by 12 per cent of the difference in case weights."

The Lyman manual simply says to reduce maximum powder charges by 2 grains when using military cases.

The NRA manual goes on to say, "It will be found that quasi-military rifles, such as the Springfield Armory M1A, function more reliably with military cases than with thin-walled commercial cases, and military or thick-walled commercial cases should be used in such weapons. Sporting autoloaders such as the Remington model 742 and Winchester Model 100 usually require the use of small-base resizing dies in reloading for reliable functioning..."

Very importantly, it continues with, "The maximum average chamber pressure for the 7.62 mm NATO military loads must not exceed 50,000 p.s.i., measured in the military pressure barrel for copper crusher pressures. The commercial .308 Winchester cartridge is normally limited to a working pressure of about 52,000 c.u.p., and the maximum product average for commercial ammunition should not exceed 55,200 c.u.p.", which I hope clears up some misunderstandings.

HTH
Refinishing Guy

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"A man not shackled with the truth can win any debate."

[This message has been edited by RefinishGuy/GunThings.com (edited April 02, 2001).]

[TideWater 41009]

[QUOTE]Originally posted by EMDII:
[B]They are different, primarily in pressure and NOGO headspace.

LOTS of discussion on different measuring systems. I would load to a 2750 fps MV on 150 grain stuff, and load to peak pressures < 51,000 on other loads.
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Barrel length is an important factor in bullet velocity, and if you tried to get 2750 fps with a 147 grain bullet out of a 16" barrel, for instance, you will exceed safe pressure limits. That 2750 fps figure is correct, but (my understanding) is that this is from a 24" barrel. Also, that 2750 fps figure is the nominal instrumental velocity taken 78 feet from the muzzle, as is U.S. military testing proceedure. The 2750 fps instrumental velocity corresponds to a muzzle velocity of about 2808 fps. An accepted rule of thumb, which I have found to be true, is to subtract about 25 fps for each inch of less barrel length.

Regarding headspace, if you measure various types of commercial and 7.62 NATO loaded ammo with a cartridge gauge, you will quickly discover that the NATO spec ammo is almost always kept to tighter tolerances than commercial ammo. Tightly headspaced rifles that will not easily chamber commercial ammo might chamber NATO spec ammo with no problem. In other words, NATO ammo will usually fit a minimum SAAMI headspaced chamber more readily than a good deal of commercial ammo. (I know; HERESY! LET THE FLAMES BEGIN!!!)

Refinishing Guy

[This message has been edited by RefinishGuy/GunThings.com (edited March 29, 2001).]

[rMac71]

on the nato spec brass being to minimum overall dimensions, makes perfect sense if you think about it. In a combat situation where you want ammunition to work in a variety of different rifles and MG's. You would want it to minimum dimensiions to insure reliable feeding and fewer jams. For accuracy you want tighter tolerances but for reliability in multiple rifles you would want looser tolerances.
Randy

[sixplusone]

I would be interested in your comments on the Hodgdon powders listed as "Extreme" ie less sensitive to heat (or cold) Anyone tried www.Hodgdon.com (http://www.Hodgdon.com) ?