Case resizing for .308

[Joshboyfutre]

Just a couple questions about neck and full-length resizing. Does only resizing the neck make my accuracy go downhill after a few times? Should I full length resize every now and then? I have noticed after I use Nosler brass after about three reloads my accuracy seems to be dropping. LOL Although I near perfect there is a possibility that I'm just getting crummy shots, but I really don't think that's the case I even put it in a sled and still had some issues. Went ahead and cleaned all the copper fouling out of my Barrel to see if maybe that was it and going to load up a few more rounds but I'm debating on full length resizing the cases comma should I or should I keep just doing the neck? I have always gotten very good advice from you guys aren't here so I appreciate anyone taking the time to read this and answer. Btw hate to hear about RCmodeler as he is one of the people that answered alot of my questions when I first started. I'll be praying for his family.

 

[W.E.G.]

Bolt guns and break-action guns benefit from neck-size only.
If you are having any trouble with neck-sized cases in bolt/break guns, you might check neck tension on your cases. In the unlikely event that tension is weak, you may want to get a different neck die that addresses that.

Guns that have to cycle the rounds through a mechanism (semi-auto, pump, lever) need to be full-length resized.

If you full-length, you need to use a case gage to be sure you set the shoulder to the correct dimension.

Please define the details of the diminished accuracy you reported.

 

[USSR]

Should I full length resize every now and then?

Yes. Eventually, the shoulder will lengthen to the point that there will be resistance when you close your bolt. At that point you will know that it's time to FL size your brass.

Don

 

[Joshboyfutre]

The drop and accuracy is minimal but I'm trying to shoot sub MOA groups. Like I said my Barrel probably just needed cleaned but it got me to thinking I never full size my cases for my bolt rifles and thought maybe there was something going on that I didn't know about. I think neck tension is good and headspace is alright because I can close the bolt without any resistance. Next reasonably warm day I might full length size some and next size the others and see if there's any difference

 

[Fine Figure of a Man]

Neck sizing usually improves accuracy. I get 6 to 8 firings before I need to full length size and use Redding competition shell holders when I do to bump the shoulder as little as possible. There is a small but measurable increase in my group sizes with full length sized brass. Are the lengths and weights of your brass consistent?

 

[243winxb]

I might full length size some and next size the others and see if there's any difference

Always best to do your own testing.

Using standard RCBS dies, FL was more accurate for me.

Standard dies, using an expander, may thin the neck case wall after 3 loadings. This can hurt accuracy.
This happens when the die over works the brass.

 

[Bart B.]

Yes, neck only sizing cases eventually requires they be full length sized. The reason is when the bolt starts to bind chambering a round, the bolt head doesn't fit the same for each one. That causes accuracy problems by making the barrel vibrate different for each bullet going through it.

Proper full length sized 308 Win cases has produced best accuracy since its inception in the early 1950's. I and others get better accuracy with new cases compared to neck only sized cases. Such dies keep the case neck perfectly aligned with the case shoulder which is what centers the case in the chamber shoulder when fired. And case bodies get sized down a little so their slight out-of-round condition doesn't interfere with a slight out-of-round chamber; they're clear of the chamber wall except where their back end is against the chamber wall.

Full length sizing has been popular in benchrest competition for near 20 years. Their smallest groups stayed the same size but their biggest ones got smaller.

In match grade semiauto M14 and M1 service rifles, new 308 Win cases hand loaded with good components would test 4" at 600 yards. Full length sizing those cases then reloading them with the same components would test 8 to 10 inches.

Use the right comp. shell holder to set fired case shoulders back .002" as it stops against the die.

If you use a die whose neck diameter is .002" smaller than a loaded round neck, you can get a few dozen reloads per case. Won't need to use the expander ball.

 

[FROGO207]

After four reloads I anneal my brass before using it again. This helps with retaining constant neck tension and helps prevent neck splits in my reloads. I mostly full length size my brass as well. On my 303 Brit I do neck size only to extend case life though. YMMV

 

[Joshboyfutre]

Thanks guy's, great advice as usual!!

 

[Joshboyfutre]

BartB, So as far as case sizing 308 I'll probably just go ahead and start full-length sizing every time, what about 223 bolt action should I be resizing that full length or just neck? Basically is what you said about 3:08 apply to every chamber?

 

[Bart B.]

BartB, So as far as case sizing 308 I'll probably just go ahead and start full-length sizing every time,

Good idea.

Do you have a way to precisely measure cases from head to some point on their shoulder?

what about 223 bolt action should I be resizing that full length or just neck?

Full length.

Basically is what you said about 308 apply to every chamber?

Yes

 

[Orcon]

To piggy-back off of Barts suggestion of .002" neck tension.

.
If you use a die whose neck diameter is .002" smaller than a loaded round neck, you can get a few dozen reloads per case. Won't need to use the expander ball.

This is such good advice. Expander balls cause me to lose sleep and gnash my teeth. You can send your dies in to have this done (Forster comes to mind) or with a bit of creativity and some 800 grit, can be done yourself. My loaded .308 Win necks measure .336" so I honed my die to size .3345". They resize and seat bullets like a dream. You'll never want to see an expander ever again.

 

[Walkalong]

Get a full length bushing style sizer or get Forster to hone your die neck. The bushing dies are more versatile, but honing the die is likely the best way. If you have a die honed, either continue to use the same brass/brass with the same neck thickness or brass with thicker necks and turn them to match the die.

 

[Bart B.]

Get a full length bushing style sizer or get Forster to hone your die neck

I think Forster only hones out their own dies. That now costs $12 plus shipping. Would be nice if they would hone out other brands even if they charged $3.21 extra.

 

[USSR]

Almost to a man, the guys I shot 1,000 yard F Class with used bushing dies. We found minimal neck tension to work best. Of course, we were single loading. I got my Redding bushing dies before they came out with their line of full length bushing dies. So, I was using their body die in conjunction with their neck sizing bushing die. Essentially full length resizing in 2 separate operations.

Don

 

[Sunray]

Neck sizing or FL sizing has nothing to do with accuracy.
Eventually, you will have to FL resize whether you like or or not. The reason is because the cases will stretch a tick in every direction with every firing. Neck sizing doesn't fix that. They'll get work hardened too. One cracked case mouth or neck, pitch that one and anneal the rest. Probably a good time to FL resize too.
It's FL resize only for semi-auto's, lever and pump actions. Neck sizing only is for bolt actions and only the cases fired out of that particular rifle. Any cases your buy new or once fired require FL resizing, first.
You can set up an FL sizer to neck size, but it's a time consuming trial and error thing.

 

[Joshboyfutre]

[QUOTE="Bart B., post: 10503913, member: 69423"
Do you have a way to precisely measure cases from head to some point on their shoulder?

Unfortunately I don't have anything at the moment. Gonna order one this week when I get paid though.

So basically the only reason to neck size a case is simply to get longer life out of it? I was under the impression that it helped with accuracy because it was a better fit for the particular chamber that it was fired out of, but, It really makes sense that I would want to full length size it now that I think about it because if the chambers out of spec at all I would have to put the brass in the exact same way every time. I think I'm going to invest in a high speed resizing die like you guys are talking about that doesn't use the expander ball.

BTW I really appreciate guys with your level if experience taking the time to explain these tricks of the trade to us FNG's. Makes life alot easier, groups alot tighter, and mainly, reloading alot more safe! Thanks man.

 

[Bart B.]

Neck sizing or FL sizing has nothing to do with accuracy.

There are people who have and use all the right stuff required to tell the difference.

because the cases will stretch a tick in every direction with every firing

All of my bottleneck cases are a few thousandths shorter (head to mouth length) after firing. Their body squeezes down and shoulder sets back a little from full length sizing that pushes their necks out longer. Cases grow a few ten-thousandths inch each cycle. Meanwhile, their dimensions between head and neck go back and forth a couple thousandths inch between their fired and sized dimensions that don't change.

Any cases your buy new or once fired require FL resizing, first.

Why new cases? All the new cases I've bought are already full length sized; they're made that way. How else would they be the shape and size they are?

Do you have to full length size new commercial match ammo's cases?

 

[Orcon]

Any cases your buy new or once fired require FL resizing, first.

Why FL size new cases? New brass is always much shorter than my fired brass. Neck size maybe, especially if you're buying Winchester brass, my last batch of 300WSM brass I think there were only 5 round mouths in a hundred cases. But if you're going with higher quality (Lapua, Norma) then there's really no need...unless you have an undersized chamber.

 

[Bart B.]

Neck size maybe, especially if you're buying Winchester brass, my last batch of 300WSM brass I think there were only 5 round mouths in a hundred cases.

To me, that's neck prepping. I think all commercial match ammo shops neck preps their cases before loading them. That ensures uniform bullet release force needed to start the bullet out of the neck. A good thing to do.

A bunch of us getting ammo ready for a big match used a Lyman M expander die to uniform new 308 Winchester case mouths. That ammo shot under 2/3 MOA at 600 yards in a couple dozen rifles.

 

[USSR]

Sunray said: ↑
Any cases your buy new or once fired require FL resizing, first.

Why FL size new cases? New brass is always much shorter than my fired brass. Neck size maybe, especially if you're buying Winchester brass, my last batch of 300WSM brass I think there were only 5 round mouths in a hundred cases. But if you're going with higher quality (Lapua, Norma) then there's really no need...unless you have an undersized chamber.

They send different brass North of the Border.

Don

 

[Walkalong]

They'll get work hardened too. One cracked case mouth or neck, pitch that one and anneal the rest. Probably a good time to FL resize too.

That's too late for annealing, it should be done after the third firing at the most if one wants to keep the brass soft and neck tension consistent. You can always decrease the size of the bushing as you go, but many people anneal every time now. Some don't at all, but the necks will work harden, resist sizing, and neck tension will change.

 

[chas442]

Adjusting your FL sizing dies to give you 0.002" or any amount you choose is easy enough. Start with a fired case that is intended to going back into the same rifle. I do this for my 338 LM. Take a pistol cartridge and place the mouth end on the fired rifle case so that it only contacts the shoulder about midpoint. Take a caliper and measure from the base of the fired case to the base of the pistol case resting on the shoulder. This should give you a measurement at the datum point or at least close. Now try to resize the case without actually bumping the shoulder. If you are successful, adjust the resizing die down an 1/8 of a turn and measure again. keep doing that until you get the amount of shoulder bump that fits your requirements.

 

[Bart B.]

Now try to resize the case without actually bumping the shoulder. If you are successful, adjust the resizing die down an 1/8 of a turn and measure again.

i think 1/8th turn is too much per step. That's .009" and the issue to resolve is much smaller.

Instead, put some labels on the die lock ring that's graduated in .002" steps; 1/36th of a turn. A little less than a 1/10th inch change about the die circumference. See post #9 in:

https://www.thehighroad.org/index.php?threads/headspace.815278/#post-10440532

 

[Walkalong]

i think 1/8th turn this too much per step. That's .009" and the issue to resolve is much smaller.

Agreed.