Virgin versus once fired brass for accuracy, ??Best??

[cdherman]

New Savage 270 WSM.

300 rds new Rem brass.

I'd like to jump right in and start looking for an accurate load, but there are two issues. One is that its usually though that barrels break in some and accuracy improves. I am considering doing some Tubb's Final Finish (abrasive bullets) to speed the break in up. But that's not the question of this thread.

The question I have is -- will I get better results if I once fire my cases and then full lenght resize (or perhaps better still, just resize till they chamber and cycle reliably in my gun)? In other words, "set the neck back a few thou make it chamber nice".

I think I know the answer and have pretty much answered my own question, but I'd like to hear it from others as well.

I'm thinking some cheap bullets and powder and go shooting, loading up a 100 rounds, in various recipe's. Obviously the accuracy will be suboptimal, particularly since I'll be cleaning a lot at first in the breakin. If initial accuracy is pretty good with cheap stuff, perhaps I'll forget about the Tubbs and just move on to final load developement.

Thoughts???

 

[Gene]

I doubt you will find much difference in accuracy. Virgin brass will expand to fill the chamber in your barrel. There is no need to full length resize until it grows at the shoulder, then you need to bump it back very slightly. With hunting rifles I full length resize every time; competition rifles I prefer to neck size only. I think you mean "set the shoulder back (not neck). Excessive shoulder push back creates excessive headspace; not good. Read your die instructions - they tell you to lower your die by very small increments until it chambers smoothly.



enough

New Savage 270 WSM.

300 rds new Rem brass.

I'd like to jump right in and start looking for an accurate load, but there are two issues. One is that its usually though that barrels break in some and accuracy improves. I am considering doing some Tubb's Final Finish (abrasive bullets) to speed the break in up. But that's not the question of this thread.

The question I have is -- will I get better results if I once fire my cases and then full lenght resize (or perhaps better still, just resize till they chamber and cycle reliably in my gun)? In other words, "set the neck back a few thou make it chamber nice".

I think I know the answer and have pretty much answered my own question, but I'd like to hear it from others as well.

I'm thinking some cheap bullets and powder and go shooting, loading up a 100 rounds, in various recipe's. Obviously the accuracy will be suboptimal, particularly since I'll be cleaning a lot at first in the breakin. If initial accuracy is pretty good with cheap stuff, perhaps I'll forget about the Tubbs and just move on to final load developement.

Thoughts???

 

[EddieHarren]

I would shoot the rifle and use the "break-in" method that you are most comfortable with. I would also avoid any abrasive treatment. Abrasives are only needed if the barrel will not stop copper fouling. Clean the bore thoroughly and use a good copper solvent.

 

[RT2506]

I made it a practice to do my accuracy work with at least once fired cases. Here is the reason why. Once upon a time I bought a new Remington 700 stainless 7 mm mag rifle and 100 new cases. I free floated the barrel and adjusted the trigger to 2 lbs that I like on a hunting rifle. I started my load work-up using the new cases only. I could not get that rifle to shoot 3 shots under 1 3/4 inch @ 100 yards to save me. One day I decided to size some of the cases that I had fired in the rifle. I sized them only part way in a FL die. I just made them fit the chamber nice. I loaded up some of the best loads so far. When I went to the range and upon firing two shots there was only one hole in the target. I thought S#*+ , GREAT! Now the thing won't even hit the paper! Then I fired another shot and when I looked in the spotting scope I thought light bulb that hole looks just a little bit large for a 7mm bullet hole. I fired again. The hole looked just a tad bit larger. I began to get the shakes and fired the fifth and last shot. When I looked through the spotting scope I could see what looked like 1 1/2 bullet holes together. I went down range and low and behold there were five shots in one ragged hole . I later found that this rifle would shoot almost anything you put into it under 1 inch if you used a once or more fired case even if it was FL sized. That is the reason I use once fired cases. Your mileage might differ.

 

[Derek M.]

Here's some info from a prominent barrel maker when asking about virgin v. once fired brass:

"On case roundness and many like tests that sound good I have found they do almost nothing. Of interest to this my friend Col. Sam Burkhalter spent a lot of time with the AMU. They found full length sized case worked better than neck sized. Don't know if I mentioned this in the past to you. Back about 10 years or so ago I went through all the case selection measure base web and etc. Weighed everything. Went to Racine for practice and shot a really good 600 yards. Told the guys what I had done and reached into to my box to wave the box of ammo in front of them. OOPS, I had shot the box of culls by mistake. This proved to me how much is what the shooter does. I assumed no error in the ammo to blame so I simply did a better job as nothing else to blame it on.

Oh, what most don't see I have. I have a lot of pressure barrels and done a lot of pressure testing. Talk about touching lands: In a number of cases this causes pressure spikes. Worked with Federal on a project why some 6mm would blow primers. It happened in rough throated factory barrels which randomly slowed down the bullet motion at start. This is why touching is wrong as you cause the base of the bullet to distort more. Also you don't compress metal for the lands, it must move which is in length so a small jump actually helps you start. Also for alignment a throat wears faster at 6 O'clock then at the top so when touching it will tip. So much of what's common idea is simply male bovine excrement."

 

[Mikecr]

Everything suggested by that barrel maker was excrement.
What the heck would a barrel maker know anyway?

 

[Derek M.]

Everything suggested by that barrel maker was excrement.
What the heck would a barrel maker know anyway?

Sarcasm on or off?

 

[Mikecr]

Well let me say this;
It's very easy to suggest that nothing done matters, when you don't actually know what does matter.

Some guy shot alright in competition using crooked ammo... Doesn't mean straight ammo is a waste of time.
He miraculously discovered that seating bullets against the lands, raises pressure.. Wow

If there was ever a barrel maker who knew what matters in AMMO, or even what makes one BARREL better than another, everything in shooting today would be way different.
The fact is, they don't. They make barrels like everybody else & we buy them -like everybody else.

Now, I don't know the answers either. Never claimed to. But I don't take stock in clan loar, heresay, anecdotal conclusions, or anything out of competition -as significant in the real world. Afterall, most competitors, don't win jack.
I'll say that in my experience, the best ammo you can make doesn't hurt a thing. And anything that helps YOUR barrel/ammo shoot better is a good thing -for YOU.

If your chamber likes new/loose brass better you can bet there is a reason, whether understood or not. But it doesn't really apply to everybody else..
Some of us have reduced ES and improved LR shooting by matching h20 capacity, which is only practical with fully fireformed brass. Some of us have to fireform just to produce our finished cartridges and get headspace right. Most of us re-use brass, simple as that.
I don't see how any conclusions can be drawn across the board though.

 

[Derek M.]

I'll say that in my experience, the best ammo you can make doesn't hurt a thing. And anything that helps YOUR barrel/ammo shoot better is a good thing -for YOU.

My thoughts exactly. Which was pretty much my response.

What sparked the conversation b/w the 2 of us was my comment that I have found once fired brass to be more accurate for me, even Lapua. I just proved it again for about the 100th time at the range yesterday with a 270 Ruger that sports a #1 Hart SS bbl. I began with 100 pieces of new WW cases that were wt. sorted, and prepped. The neck OD when loaded are 0.303. My die sizes them to 0.3015 w/o the expander.

I found a promising load with the 110 Barnes TTSX and 58.0 H4350. The rifle shot repeatable 5/8" groups down to 3/8".

I cleaned the fired brass, sized it, annealed the necks, and repeated the loads yesterday. No group was over 3/8" for 3 shot strings. Not bad for a bbl almost 26", long and skinny, not to mention a Ruger action.

 

[dmgreene]

I know that I have 22-250 that will not group worth a crap with virgin brass because of a little to much headspace. There is a huge difference in virgin and once fired with it.
On the other hand my 6.5-284 shows no difference between virgin and once fired brass. Use your virgin brass to work up your loads and break your barrel in and I'll bet you that the load that was most accurate with virgin brass will be the most accurate with once fired brass also.

David

 

[royinidaho]

From the above posts I'm assuming that most comments are regarding factory barrels.

I'd like to start a discussion with Eddie, but I'm smarter than that, I'm pretty sure, well maybe. I'd most probably learn enough to become even more dangerous.

I wonder if the rules change with a high intensity/extreme cartridge with a really fast twist. If they do I'd like to start a discussion with Derek M, about into the lands or not. Again I'm smarter than that. Though not much.

My experience with a cartridge that requires fire forming causes to agree with mikecr's last statement "I don't see how any conclusions can be drawn across the board though."

I as well as others notice a bit of a difference in accuracy when using the COW method of fire forming. The difference is evident between the first and second "real" shot. One has to look really hard to see it but it's there.

I've been using a stout load for fire forming to develop drop charts etc and use them for "rifle golf" and they are plenty good enough. Being anal though, I verify after the first use of the case.

After the second firing of the case there is no more fiddling just shootin'.

 

[davewilson]

i have an edge which requires expanding of the necks. it wasn't my intent, but i have to clean the necks a bit to chamber loaded rounds. i'm convinced the accuracy is as good with virgin brass as fireformed, if not better. i only shoot FL sized ammo though.

 

[cdherman]

Use your virgin brass to work up your loads and break your barrel in and I'll bet you that the load that was most accurate with virgin brass will be the most accurate with once fired brass also.

David

Well, that's a theory as well, but one that also depends a lot on how much the case has changed, whether the neck is griping the bullet the same etc etc.

I *hope* you are right, but I know from experience that best accuracy combinations do vary between brass manufactureres (meaning the best load for a given gun using WW brass may be different than the best load for Rem Brass).

I think I am going to try several powders and bullets while running the first 50-100 rounds through the gun.

If they all suck, I'll try prepping some of the same load in once fired brass and see what I get.

If that still doesn't work, then its time for Tubb's abrasive Final Finish bullets.

And if its still scattering the slugs all around, well then I'll be quite unhappy...... I rally want 1/2 MOA accuacy out of this rig....