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Charge WT vs Explosive WT

4K views 35 replies 8 participants last post by  Sniper03 
#1 ·
Okay, I plan on loading 308 Winchester using IMR 4064, 201M primers, Federal and LC brass. I see this calls for Federal brass but do not know the difference between charge weight vs explosive wt and do not want to make a mistake. Does anyone out here know for sure what these are and can tell me if I can use the same load in LC as I plan on doing with Federal. I see a lot
242059
of do's and don't out here but who knows what to believe.
 
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#2 ·
What type of card is that? Is it some military spec? It shows to be 12 years old. YIKES! Don't go by that card!
If I were you I would buy a current reloading manual and go by what it shows for powders and recommended loads per each bullet weight you use. Hogdon has an online manual with all their and IMR powders and recommended loads for free.
 
#3 ·
STOP.
Either go to the website for the company that makes the powder you want to use, or get a good loading manual.

Your card is a military spec sheet that includes classification info for shipping. Also please show me on that sheet where it says .308. If it does, I need to get my glasses checked. .308 is NOT 7.62 NATO.

There ARE some .308 loads that use 175 gr Sierra Match King bullets and IMR 4064- that with the right rifle, can shoot sub MOA groups. But please go look those up. Myself, I like Lyman and Hornady manuals, but that is a matter of taste.
 
#4 ·
STOP.
Either go to the website for the company that makes the powder you want to use, or get a good loading manual.

Your card is a military spec sheet that includes classification info for shipping. Also please show me on that sheet where it says .308. If it does, I need to get my glasses checked. .308 is NOT 7.62 NATO.

There ARE some .308 loads that use 175 gr Sierra Match King bullets and IMR 4064- that with the right rifle, can shoot sub MOA groups. But please go look those up. Myself, I like Lyman and Hornady manuals, but that is a matter of taste.
What is the difference between ( charge wt and explosive wt ) as shown on the card and what round has higher SAMMI pressure 308 or NATO
 
#5 ·
The explosive weight is the total weight of the contents minus bullets and brass in a shipping container. It has absolutely nothing to do with the amount of powder per cartridge; it is the total powder and primers weight per container of loaded ammunition. As mentioned by others, do not use this as any sort of load data. Get a good book or use online data....this is not load data!
 
#6 ·
Okay, I just wonder why this is being said since it shows what the load is, what powder to use, the bullet, brass, primer etc and form my understanding this is a M116 load which is good for M1A which I hear had issues with a bar that use to break if it got to much gas pressure. Wouldn't this mean this is a low pressure load to where is a M1A can take the pressure a 308 surely should. The one book I do have should the 308 max load for 4064 is ( 39.5 to 41.3 gr.) and I have read out here on one of the post where some said 41.7 gr was making a clover leaf group at 100 yards. Then I have another book that says max load should be 39 gr of 4064. What in the world is anyone to believe. I guess I'm back to the same question. Is 7.62 NATO a higher pressure cartridge than a 308 Winchester
 
#8 ·




Also, get manuals.
 
#12 ·
The best way to get the most accurate load for a given cartridge/rifle is to carefully work up your own loads from established load data...you seem intent on grabbing the magic load or something. I am not trying to be sarcastic, but you seem obsessed with this 4064 load that may or may not be worth the effort for your rifle. LC brass is good brass...work up a load!
 
#14 ·
Yeah, 4064 is all I have and can't get anything else now. Heck I can't even get primers, bullets or powder and have been told by the vendors I go to nothing will be available to Aug of 2021. I also noticed there's a lot of price gouging going on by those who do have some of these components in stock. Yes, I am a magic load gobbler and do not want to spend forever or hundreds of dollars trying to get a bullet to go in the same hole at 100 yards. In my 700R5 and TAC 21 I actually found that 168 gr hpbtmk factory federal ammo shot 1/2 MOA but at $47 a box of 20 I just could not afford that since I usually shot 60 - 100 rds per visit to the range and am not happy if I'm not shooting 1/2 MOA. This is what I want from the 175 gr so I can start reaching out beyond 400 yards and maybe someday out to 1000 yards. This is only to see if I can not. No hunting and no competitive class F shooting for me. Just stock off the shelf rifles to see what I can do and they can do.
 
#24 · (Edited)
US military brass is not marked with the caliber on the cartridge case. It is marked with the producing ammo plant, and the year of manufacture.

.308 Winchester is NOT 7.62 NATO. They have similar external dimensions. Military brass is heavier, and has a smaller case capacity- all other things being equal, and that will give higher pressures. 7.62 cases hold 3.38 ml, 308 Winchester holds 3.64 ml. Barrels are usually the toughest component- the action and the bolt will be weaker. The component parts of a reload are brass, primer, powder, bullet. When you change any one of the 4, drop back to starting load and work up.

There IS no SAAMI spec for 7.62 NATO. SAAMI specs are for SPORTING ammo. However, pressures for .308 can run higher than for 7.62 NATO.

Note from Wikipedia:
The dimensions of .308 Winchester are almost the same as 7.62×51mm NATO. The chamber of the former has a marginally shorter headspace and thinner case walls than the latter due to changed specifications between 1952 and 1954. This allows 7.62×51mm NATO ammunition to feed reliably in rifles chambered for .308 Winchester, but can cause .308 Winchester ammunition cases to rupture when fired in rifles chambered for 7.62×51mm NATO.
 
#25 ·
US military brass is not marked with the caliber on the cartridge case. It is marked with the producing ammo plant, and the year of manufacture.

.308 Winchester is NOT 7.62 NATO. They have similar external dimensions. Military brass is heavier, and has a smaller case capacity- all other things being equal, and that will give higher pressures. 7.62 cases hold 3.38 ml, 308 Winchester holds 3.64 ml. Barrels are usually the toughest component- the action and the bolt will be weaker. The component parts of a reload are brass, primer, powder, bullet. When you change any one of the 4, drop back to starting load and work up.

There IS no SAAMI spec for 7.62 NATO. SAAMI specs are for SPORTING ammo. However, pressures for .308 can run higher than for 7.62 NATO.

Note from Wikipedia:
The dimensions of .308 Winchester are almost the same as 7.62×51mm NATO. The chamber of the former has a marginally shorter headspace and thinner case walls than the latter due to changed specifications between 1952 and 1954. This allows 7.62×51mm NATO ammunition to feed reliably in rifles chambered for .308 Winchester, but can cause .308 Winchester ammunition cases to rupture when fired in rifles chambered for 7.62×51mm NATO.
So its the actions that are weak. I sure hope my two Remington 700 are strong enough to take max loads that's shown in the book. Sure wish it was require for all these rifle manufactures to test their final product to 400% max pressure and have it hold without a defect. It would be safer for all.
 
#28 · (Edited)
Problem comes because the US military and SAAMI use different testing systems that are not directly comparable. Europe uses the CIP protocol.

To complicate things further NATO uses a different system called EPVAT in testing of 5.56mm, 7.62mm, 9mm and .50 caliber ammunition. EPVAT pressures are not directly comparable to CIP or SAAMI.

NATO EPVAT testing | Military Wiki | Fandom (wikia.org)

Modern bolt action rifles are very strong. Unless a reloader does something industrial strength ignorant it is highly unlikely that a modern bolt action rifle will "blow up". "Blowups' usually happen because someone used the wrong powder or the rifle had a bore obstruction. i was present on a firing range when the shooter at the next bench had a beautiful pre-war model 70 Winchester rifle self destruct when the cartridge case separated near the base. By his own admission the powder load was outside maximum.

Been reloading .308 ammunition since about 1965. At that time i did some serious testing using most of the suitable powders at that time. For reloading bullets of 150 grains and less i chose IMR 3031. Have tried some of the newer powders and see no reason to change.
 
#29 · (Edited)
Problem comes because the US military and SAAMI use different testing systems that are not directly comparable. Europe uses the CIP protocol.

To complicate things further NATO uses a different system called EPVAT in testing of 5.56mm, 7.62mm, 9mm and .50 caliber ammunition. EPVAT pressures are not directly comparable to CIP or SAAMI.

NATO EPVAT testing | Military Wiki | Fandom (wikia.org)

Modern bolt action rifles are very strong. Unless a reloader does something industrially strength ignorant it is highly unlikely that a modern bolt action rifle will "blow up". "Blowups' usually happen because someone used the wrong powder or the rifle had a bore obstruction. i was present on a firing range when the shooter at the next bench had a beautiful pre-war model 70 Winchester rifle self destruct when the cartridge case separated near the base. By his own admission the powder load was outside maximum.

Been reloading .308 ammunition since about 1965. At that time i did some serious testing using most of the suitable powders at that time. For reloading bullets of 150 grains and less i chose IMR 3031. Have tried some of the newer powders and see no reason to change.
Holy smokes. The EPVAT is extremely detailed but I can see where it may be better but still wondering if civilian gun manufacture use the higher pressure ammo to test their goods. Thank you again for the information. Had no idea there was any other test except for CIP and SAMMI
 
#30 · (Edited)
nvrpc

As C-3 and others have mentioned a good Reloading Manual is an absolute!
In fact I have three different Manuals. But as they have advised there is some difference in the Volume of the Lake City Brass. The Speer Manual #14 Mentions a reduction of the Powder Loaded by 3% on the Max Load Specs.
Others say minus 2-3 Grains on the top end. But besides that IMO I do not know why anyone thinks they need to load their ammunition to MAX Load anyway. 99% of the time that is not where the most accurate loads will exist.
Being an "accuracy freak" and hunter with the 308 for years I have found it usually somewhere around the Middle or somewhere between the Middle and the Max.

For example here is one of the accurate loads for for the 308 I have used with Factory Brass is:
41 gr. of 4895 with 168 gr, Sierra BT HP. *The Best. But with Lake City that load would also be OK. Because as I stated I do not ever load anything to Max because the peak accuracy is not there!
I also had another load that was good with 42 Grains of H335 with the same Sierra Bullet.

But you "MUST" get a good Quality Reloading Manual and go by it!! (y) But if loading Max Loads you must remember to reduce the powder load!

*Every Rifle is different and as we say, what it likes to Eat. You will know when you get to the right combination Powder, Powder Charge, Bullet seating depth and other aspects. Because your Groups will tighten up like a Hangman's Noose!

Good Luck!

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#31 ·
Well I guess you can't edit post so I continue here. I was also told I will have to get myself a magnitospeed to know what my MV is so I can plug that figure into my Kestrel 5700 so it can figure out my elevation even if I use their custom bullet profiles. I hate spending that type of money but it looks as if I really don't have a choice if I want to be on at 1000 yards. This of course does not take in windage issues
 
#32 ·
nvrpc1

What Rifle are you going to be using? And Barrel Length (308). I can give you my range information I have with my Remington 40X. I have shot 1000 yard targets and have the Elevation Dope for it. Yours will probably be slightly different but at least it will give you a ball park to work with. In fact I did not hit the Target all the time, but have shot up to1400 yards. And by the way if you are going to ever shoot over 600 yards you are going to need a 20 MOA Base to mount your Rings and Scope on. If you would like to have my elevation adjustments just let me know!

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#34 ·
nvrpc1

Both are very fine rifles! Do you have a 20MOA Base on either of them? Excellent Scope Choice. I have an Leupold Long Range M-1 Mil Dot Reticle on the 40X. It has always served me well.
And I have a Leupold M-4 on my 338 Lapua Magnum Rifle (Savage)
Can't beat them for the Quality and Price! (y)
03
 
#35 · (Edited)
nvrpc1

Both are very fine rifles! Do you have a 20MOA Base on either of them? Excellent Scope Choice. I have an Leupold Long Range M-1 Mil Dot Reticle on the 40X. It has always served me well.
And I have a Leupold M-4 on my 338 Lapua Magnum Rifle (Savage)
Can't beat them for the Quality and Price! (y)
03
No I do not. So I may be out of luck but I was told 1000 yard shots could be made with this scope without the 20 MOA base. I just don't know. Maybe these people that are using this are running full turret travel and then using some reticle holdover too. I am using this reticle - TMR Reticle | Leupold I just checked the scope and the top turret has 23 mils of adjustment. I then went in the Kestrel and put in all the data for 175 gr hpbtmk at 1000 yards and it said to dial in 12.18 mil. U that of course was based on a MV of 2549 FPS. Since I have ( 10 clicks = 1mil ) I thinking I should have the kestrel set up for mil not the reading that tells me I have to go U 121.18.
 
#36 · (Edited)
nvrpc1

Yes they are correct, if you are going to use Mils for Holdovers. Although you will have to learn how much each Mil represents at each distance. IMO it makes it more difficult for me to remember exactly the value at various distances. And especially for any targets anywhere within a known range. That is why I always use the Mils to determine the distance range wise. But I us MOA Adjustments to set the Scope exactly to the precise distance.
Formula: Size of the Target in Inches X 27.8 (in reality it is 27.777inches) Divided by the Mils of the Scope. = Range Distance. Example: 72 in (6ft.Man) X 27.8 = 2001.6 Divided by 5 Mils = 400.3 Yards. For my 40X that would be 8 MOA Adjustment from 100 yard Zero. This is the easier Formula to use!
So lets say the Range to the Target was 350 Yards! I have my MOA adjustment exactly needed for that on the side on my Sniper Rifle as in the Pictures of the 40X. I do use Mil Holds on Wind!
Brown Publication Fluid Tints and shades Font
Audio equipment Font Fashion accessory Ink Liqueur
Air gun Trigger Wood Shotgun Gun barrel


* Just for clarification in the Stock Picture the " - " sign after the 27.8 is a Division Sign and . also the Wind Chart on my Stock. No key was available to print the Division Sign!

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