308 Load Data

[Adam_MA]

For the bullets I have (Sierra 168gr BTHP) and the powder (IMR 4895) my loading manual puts the powder charge between.

38gr - 43.5gr

I am looking to work up a load that I will be using in my bolt rifle. I think I will start with 20 rounds for the first batch, and I am thinking that I should start somewhere around 41gr of powder. I would like to work up to probably a max of 42.5gr of powder.

How does the following sound?

2 rounds at 41 gr
2 rounds at 41.2gr
2 rounds at 41.4gr
2 rounds at 41.6gr
2 rounds at 41.8gr
2 rounds at 42gr
2 rounds at 42.2gr
2 rounds at 42.3gr
4 rounds at 42.5gr

Does that seem to be a logical progression for working up to the load that I think will work the best?

Any other suggestions?

Thanks
Adam

 

[TonyD]

Adam - You won't be able to tell a thing by shooting only two rounds of a certain load. You'll need to load at least five of each to check a group, or if you have 300 yards you can try the "Ladder" method. I've not tried that yet but will the next time I need to work up a new charge.

 

[Adam_MA]

Good point Tony,
I only have 200 yards at my range, and I mostly shoot at 100.

I guess I should maybe go more with something like this then.

5 rounds at 41gr
5 rounds at 41.5gr
5 rounds at 42gr
5 rounds at 42.5gr

I guess that will get me there with enough stops in between to check for signs of over pressure and such.

Do you have a link with more info about the "Ladder" method? I am interested in what it's about.

Thanks
Adam

 

[TonyD]

No link. It was explained to me by an experienced reloader.

Basically:

Pick the powder range you want to try (somewhere in the middle to upper 2/3 range) and load one round of each. Make sure to keep seperate and mark them so you know what each one is.

At the range, start with the lowest charge and fire that round. Go down range and mark it. It should be low on the target. Do this with each round. As the velocity increases with each round, they will work themselves up the target like a ladder, each one higher than the next.

Somewhere, you should end up with 2, 3 or 4 holes being closer together than the rest. Go back and load up 5 - 10 rounds of each of those charges and see which holds the tightest group.

Of the original rounds, you should load them about .2gr increments. Half a grain difference is too much of a spread when you're working up a load.

Apparently, you really need 300 yards for the difference in velocities to work up the target and for the "group" to appear.

If done properly you can work up a load in about 25 rounds instead of a hundred.

 

[Adam_MA]

Of the original rounds, you should load them about .2gr increments. Half a grain difference is too much of a spread when you're working up a load.

Did you mean this as a general rule, or just while referring to the Ladder method?

If so, maybe I will have to rethink my progression.

Adam

 

[TonyD]

Did you mean this as a general rule, or just while referring to the Ladder method?

If so, maybe I will have to rethink my progression.

Adam

As a general rule. There is a big difference in .5 grains and you need to be able to look for pressure signs before that.

 

[Adam_MA]

So would you think a work-up like this would be more sufficient?

41.5
41.7
41.9
42.1
42.3
42.5
5 rounds each.
Also, I was playing around with my powder measure last night getting it set for tomorrow, and I can't believe how full the case ends up being. Almost up to the bottom of the case neck.. Just didn't expect it, but the new Lee powder measure is dead on, throw after throw.

Adam

 

[Nickle]

Adam, the MILSPEC M852 Match load calls for 42 gr of 4895. That would be H4895. You'll find out it's not a mild load in most cases.

A warning. H4895 and IMR 4895 have a very touchy pressure curve. When pressure starts to go up, it does it very quickly. When using these powders, make sure to check the powder level before seating the bullet. I had to learn the hard way, and got lucky. It only cost me about $400 to $500 to learn.

 

[Adam_MA]

Nickle,
When you say check the powder level what exactly do you mean? I threw a charge last night just to see how much it filled up the case, and it was pretty damn full. Meaning almost up to the case neck, but that was with max powder.

Even though the load data puts max at 43.5 would you recommend not going above 42 for at least the first round of loadings, or do you think going to 42.5 is reasonable. Remember this is a rifle chambered in 308 win, not 7.62 NATO, so it should be able to handle higher pressure.

Thanks
Adam

 

[Nickle]

42 wouldn't be a bad start for a strong bolt gun. The caliber difference is almost semantics.

As to the level, eyebal each one to make sure some powder didn't stick in your measure. That's what cost me the trouble and money.

 

[Adam_MA]

Thanks!

 

[Nickle]

Anytime.

 

[USSR]

Adam,

Whenever discussing load data such as this, in addition to the info you have already given, you should also mention the following: type of rifle to be used in (autoloader, bolt, etc.), make of brass used, and cartridge OAL. Someone may give you load data using commercial brass and loaded long that is perfectly safe for a bolt gun, that would be a seriously hot load in military brass in an autoloader.

Don

 

[Adam_MA]

Thanks for the tip Don.
I can't recall what the OAL is that was listed in the manual, but I am using Winchester factory new brass in my Savage 110 bolt gun.

 

[Nickle]

The 42 grain M852 load assumes you're using LC or FA Match brass. Both of these are military, and usually thicker than civilian brass.

 

[TonyD]

So would you think a work-up like this would be more sufficient?

41.5
41.7
41.9
42.1
42.3
42.5
5 rounds each.
Also, I was playing around with my powder measure last night getting it set for tomorrow, and I can't believe how full the case ends up being. Almost up to the bottom of the case neck.. Just didn't expect it, but the new Lee powder measure is dead on, throw after throw.

Adam

Those look good to work with. You might even drop the 41.9 and 42.1 and load up 5 at 42.0. You've got enough on either side to check pressure.

The cases are nearly full. In fact, some loads are "compressed" loads. Meaning that when you seat the bullet you are actually compressing the powder with the base of the bullet. Your manual should indicate if it's compressed. You'll know when you seat the bullet and hear a crunching sound.

 

[Adam_MA]

Thanks Tony!

 

[TonyD]

By the way, Adam, don't get caught up in "hot loads, and fast bullets". Higher velocity doesn't necessarily mean better accuracy. You have to find the load that shoots the best in that rifle.

 

[Adam_MA]

Yeah.. I'm not one to want to push the limits of ballistics. Especially when my cheek is firmly pressed against the stock, with the bolt facing my eye, and the chamber only a few inches away.

Good advice though.
Thanks
Adam

 

[USSR]

Thanks for the tip Don.
I can't recall what the OAL is that was listed in the manual, but I am using Winchester factory new brass in my Savage 110 bolt gun.

Okay. In most instances the manuals will use 2.80" for the OAL for the .308 Win. However, this does not mean that you HAVE to load to this length or even should load to this length. Let your rifle determine your OAL. With any rifle, there will be two factors that will determine the maximum OAL that you can load to: chamber length and magazine length. Whichever of the two is the shortest, that is the maximum OAL that your rifle will handle (unless your magazine length is shorter than your chamber length and you want to single-load). While magazine length is easy to figure (just load a cartridge long and seat the bullet in the case until it fits), here is how to determine how far you can seat a bullet out and fit your chamber. Stoney Point makes a tool called an OAL Guage. You buy this tool along with what they call a modified case in .308 Win. You pull your bolt out and insert this OAL Guage/modified case with the make of bullet you intend to use. You use this tool to push the bullet out of the modified case until the bullet makes contact with your throat and then lock that setting in place. When you remove the tool and bullet from your rifle, you simply measure the tool/modified case with bullet in place to determine the maximum OAL length of your chamber. When you set up your seating die, set it up to produce ammo with an OAL of .010"-.020" shorter than the OAL length that you got using the OAL Guage. Even better, you can buy a bullet comparator and measure from cartridge base to bullet ogive. The Winchester brass you are using is the lightest, and hence has the greatest case capacity. I would work up to a load of 43.6gr of IMR4895 if I was you. Depending upon your barrel length and the cartridge OAL you use, this will give you a velocity in the neighborhood of 2650fps.

Don

 

[Adam_MA]

Don,
Those sound like pretty cool tools. More than anything right now, I am trying to get a load that will be at least a match for the Federal Gold Match. With those rounds, I can get in the X ring every time, as long as I do my part. At $18 for 20 rounds, I don't get to shoot them very often though.

Adam

 

[USSR]

Adam,

With quality handloads, you will easily exceed anything you can do with Fed GMM and at less cost. I went from .75MOA to .39MOA at 100 yards. Of course, there is an upfront cost of getting the correct tools and learning what you need to do and how to do it.

Don

 

[Adam_MA]

Cool!
That's a good improvement. I'll see how it goes tomorrow, and go from there.

Adam

 

[Nickle]

If you want to really boost accuracy get a Wilson Sizer and a Wilson Seater. I have a source.

 

[TonyD]

What makes the Wilson better than anything else?

 

[Adam_MA]

Don't the Wilson dies need to be used in an arbor press? Or do they make standard dies as well?

 

[Nickle]

You ever use one? They're hand dies. Straight line, too. I make my really good ammo using them. Better aligned ammo. Truthfully you need to use an AR Race Gun or a Bolt Gun to take advantage of the accuracy.

I've shot a group that measured .204 at 200 meters using them. Of course, that was a 22 PPC, with a Hart Barrel, and McMillan stock, built on a Remington 700 Action, with a 24X (IIRC) Scope, 10 1/2 pound class (Light Varmint). I screwed up the best group I've ever shot (100 meters, the 5th shot made it about .125) using them with a .219 Donaldson Wasp, Hart Barrel, Sleeved Rem XP-100 Action, McMillan Stock, Hart trigger, Weaver T25 Scope, 13 1/2 pound class.

 

[Nickle]

Don't the Wilson dies need to be used in an arbor press? Or do they make standard dies as well?

I made my press from a bottle capper. I've used a small mallet also. The seater you can use by hand, just press down.

If you have your C&R, you can use the "M" source to get them. I think you know who "M" is.

 

[Adam_MA]

Well I made up the loads on Friday night, and made it to the range on Saturday. I found that all my loads were shooting low, but with every increase in powder they were getting higher and higher. To check zero, I shot some Federal factory ammo, and they were right on the money. I noticed that the Federal hit me in the should much more stiffly than my reloads, so it looks like I'm back to the loading bench. I think for next weekend, I will start where I left off 42.5gr, and work my way up to 43gr and see how they shoot.

Either way, I sure had fun making them, and I couldn't have asked for a better day (other than a little less wind) than Saturday to get out to the range.

Adam

 

[TonyD]

Adam, don't worry about where they hit or how hard recoil was. How were the groups???