Can I get less than half MOA from "MY" factory barrel.

[ajhardle]

I have been meaning to replace the two piece base with a quality one. Also, I haven't found someone in town to lap the 35mm rings. I know it can make a difference, but it boggles my to think it can make that much difference.
I've got 20 75 gr. Bthp leftover. I don't know if I ever tried to find OCW was. I probably bought them before I knew what that method was.

 

[Bullet bumper]

Here is my equipment.
Rifle: savage 12 in .223 with 1 in 9" twist. Boyd laminate stock with aluminum pillars and Devcon bed. By trued action, I meant squared the reciever face and lugs. Millet 6-24 lrs scope.
Loads technique: Start with new brass. full length size, then trim length, inside outside beburr, turn necks to remove metal almost 360 degrees on most brass, flashhole deburr and primer pocket uniform. After first firing, i will size with a lee collett n.s. die, (when i f/l size, the neck consricts too small and when i seat it introduces alot of run out. Bullet cant measured in runout near the meplat was measured as high as .03 from f/l sized brass. neck sizing with .001 neck consriction has reduced this reading to under .005 for all pieces, and less than half that for most. but groups didn't seem to shrink.

I trickle all powder as accurately as i can w/ an RCBS 50 50 scale.

I think my kids took my notebook, so these group sizes will be as best i can remember off the top of my head.

53 gr. smk: i started at 22.2gr of VV n133 and shot up to 23.4. goup sizes started near 2" and alternated between 1 and 1.5" near 22.8 gr. ( i shoot all groups at 200 right now because 100 yards is crowded with people trying to figure out why they can't hit paper.)

69 gr remington match loads shot 1.5"
i had some 70 gr bergers loade with about 24.5 gr of vv n140(metered not weighed) that shot about 1.5". I am going to develope a load for these, hoping they're my magic ticket.

75gr hornady match loads shot around 1.5" if i remember.

My favorite is the 75 gr amax. At 4300 elev. sg is about 1.15. not ideal for short range, but it has exceeded my expectations at long range.
i started at 23.7 gr of varget that shot 2" groups. at 24 gr it shrinks to a very consistent 1" all the way to 24.4 gr. 24.5 would shot 5 shot a group near 1" once and 1.5 and 1.7" and 24.7 was about 2" so i would say i found my node.
vertical dispersion at 800 and 900 is always sub moa.

77 smk shot close to 1.75" with n140. never better than 1.5.

my front rest is a caldwell competition benchrest rest. rear is a protektor bag on a wood block i routed out for a perfect fit with scews threaded through to bite in the concrete bench.

As for technique, i've spent countless hours laying on my basement floor practicing calming techniques, my pauses between breathes, and for trigger feel. I count one to engage the accu trigger sear safety(whatever it's called), count two is pressure on trigger, and three is a tiny bit more pressure to fire. i practice holding at two, so the smallest amount of pressure will fully engage.
I usually shoot this rifle free recoil, but i have been firming up my hold just to try it, and i have had to call a couple flyers. It did make me feel good see those shots go where i thought they would, but that turned some 1" groups into 1.5". back to free recoil.

I work hard to reduce paralax to nothing. and i will make targets or shoot at a spot for best picture. corner of a square usually. the reticle is motionless (usually, sometimes i ignore better judgement,), at least until the sun is up when i shoot, and i almost always see my reticle on target replaced by a white flash when the shot goes off.
A couple asked for more details. Sorry for writing a novel. Did i miss anything?

OK there is a few things you are doing wrong in my opinion.
First off if you still have the factory chamber then you don't turn the necks to a 100% clean up you don't need or want to do that as it will thin the neck too much and increases neck to chamber clearance. Only skim turn them to about a 70% clean up on most cases but not all the way on all cases .
Then using your Lee collet die get a large washer that goes over the 223 case and when sizing the necks it sits on the shell holder . This shortens the length that the necks get sized .
This allows a slight second shoulder to be created after firing at the base of the neck . This should be allowed to stay expanded for the life of the case.
That is accomplished by throwing the full length sizing die into the garbage bin where it belongs and buying a Redding Body die.
This die only sizes the case body and does not touch any of the neck area.
Don't body size or full length size new brass if it already fits the chamber , you are just creating more slop for the round in the chamber.
What this all achieves is an expanded portion of the neck that acts as a centering collar over the entire life of the case and reclaims back the increased neck to wall clearance caused by neck turning in a factory chamber . The body die allows fractional sizing of the case body so that only the minmum sizing is done to get it back in the chamber.
This preserves the fire formed fit of the case . By contrast the Full Lenght sizing die f*cks the fire formed fit every time . That's hard to say.
In a bolt gun you want that neat fit preserved.
There is a few other things I wanted to say but that is enough for now .

 

[ajhardle]

That's an nifty method with lee collet die. My reasoning for neck turning was that if the case centers itself at the taper of the shoulder, a case with zero runout would center the bullet in the rifling. I never thought it might center at the neck on any thing but a bench rest chamber. My brass is concentric after firing, so it sounds worth trying.

 

[FEENIX]

So yes, it's definitely possible. However, some rifles will never get close to this no matter what you do. For those there is Gunbroker.

LL! gun)

 

[Bart B]

My reasoning for neck turning was that if the case centers itself at the taper of the shoulder, a case with zero runout would center the bullet in the rifling.

That's good reasoning. Few people realize this is what happens with bottleneck cases headspacing on their shoulder. There's 4 external forces acting on a chambered round; 1 applies only when the round's pushed into the chamber and the bolt's not closed, 1 or 2 position the case after the bolt's closed then these combine with the 4th one to position the case when its fired. It's easy to check your rifle and see what they are and how they effect case positioning in the chamber.

Even a .243 Win. cartridge centers its neck and therefore the bullet, too, perfectly when chambered in a .308 Win. chamber. It doesn't matter how much clearance there is around the case neck. If the rimless bottleneck case neck's well centered on the case shoulder, they all center perfectly up front in the chamber. Even if the body diameter at the shoulder's several thousandths smaller than chamber diameter at that point. The case neck doesn't touch anything; it just sticks out from the case shoulder that's hard against and well centered on the chamber shoulder. Once one understands how a bottleneck case fits the chamber when it's loaded and fired, it makes sense. Full length sizing fired cases centers their neck better on the shoulder anyway. Dies with bushings are the best.

Sierra Bullets full length sizes all their cases (with Redding bushing or standard FL dies) used to hold bullets shot for quality control; accuracy. I doubt anybody shoots their bullets as accurate as they do. And the use standard chambers, too, no tight necked ones. Nor do they prep their cases.

 

[Bullet bumper]

That's good reasoning. Few people realize this is what happens with bottleneck cases headspacing on their shoulder. There's 4 external forces acting on a chambered round; 1 applies only when the round's pushed into the chamber and the bolt's not closed, 1 or 2 position the case after the bolt's closed then these combine with the 4th one to position the case when its fired. It's easy to check your rifle and see what they are and how they effect case positioning in the chamber.

Even a .243 Win. cartridge centers its neck and therefore the bullet, too, perfectly when chambered in a .308 Win. chamber. It doesn't matter how much clearance there is around the case neck. If the rimless bottleneck case neck's well centered on the case shoulder, they all center perfectly up front in the chamber. Even if the body diameter at the shoulder's several thousandths smaller than chamber diameter at that point. The case neck doesn't touch anything; it just sticks out from the case shoulder that's hard against and well centered on the chamber shoulder. Once one understands how a bottleneck case fits the chamber when it's loaded and fired, it makes sense. Full length sizing fired cases centers their neck better on the shoulder anyway. Dies with bushings are the best.

Sierra Bullets full length sizes all their cases (with Redding bushing or standard FL dies) used to hold bullets shot for quality control; accuracy. I doubt anybody shoots their bullets as accurate as they do. And the use standard chambers, too, no tight necked ones. Nor do they prep their cases.

This is only true to a degree. If the first chambering is an unfired case then it don't fit perfectly. If it's a new case and it's been full lenght sized it don't fit perfectly .
If the gun has a plunger type ejector the case is pushed to one side before fire forming and it don't fire form concentrically and is never concentric after that .
The skill of the re-sizer and the type of dies used also comes into it .
If you study enough chambers and cases that fit them you see that after sizing some head space on ( or are closer too) the outer edge of the shoulder , some in the middle and some right at the junction of the neck and shoulder . It all depends on the match of the sizing die to the chamber and believe me not many match perfectly .
Sierra bullets do what is normal and common so that the resulting accuracy tests a relevant to what the average shooter is doing not the precision reloader .
It is a lot easier to produce tight groups in a locked down rail gun in a windless tunnel using select match quality barrels that if a barrel don't shoot they scrap it a start again with a brand new one. That is a totally different situation to the average shooter trying to better 1/2 in a cheap factory sporter .
I came up with this system so many years ago and have had 30 years of negative comments but in the last decade or so I see even people like David Tubb have been using this system. Are you going to tell me that David Tubb does not know what he is doing .
I think German Salazar and Larry Batholamew also use this system.

 

[Bullet bumper]

That's an nifty method with lee collet die. My reasoning for neck turning was that if the case centers itself at the taper of the shoulder, a case with zero runout would center the bullet in the rifling. I never thought it might center at the neck on any thing but a bench rest chamber. My brass is concentric after firing, so it sounds worth trying.

It's a nice theory but unfortunately in practise it don't always work for a number of reasons which i have already outlined.
You must remember you are talking about chasing sub 1/2 inch groups in a factory gun . If you just want average accuracy then use average techniques.

You have to look at this technique in the correct way . Which Bart B is not .
The idea behind the expanded section of neck is :--- TO ALWAYS HAVE A CENTRED CASE FOR THE LIFE OF THE CASE EVEN IF THE BODY IS SIZED A BIT TOO MUCH OR THE SHOULDER IS BUMPED A BIT TOO MUCH . It's a safety belt .
Every time you put a fired case in a sizing die you change the fit . Some dies work better than others and some reloaders work better than others but if you thin the necks by turning and then expect the shoulder to do all the alignment then you better be real good at perfect minimum resizing each time . Only body dies can do that well.
This was the system I came up with that resulted in me making my first body die back in 1968 or so by cutting the tops off and drilling out the neck of Full Length dies . I had to have a die that did not touch the neck separate to the neck size die. I know nobody believes me I don't care , I know what I have done and it has been me talking about this for many years .
You have to keep thing relevant and in context some people will not be able to work this out , some people may not have a bolt action so it's not suitable to autos . Some people will not want to change what they are doing so for them the system is no good.
It does not hurt to try new methods , it may suit your gun real good .
When you start chasing the edge of BR type accuracy don't forget the importance of " target quality " bullets . Run of the mill bullets can vary a lot and be great one time and the next batch not so good.

 

[ajhardle]

1.Okay, I. Have a plunger ejector, along with an extractor that doesn't work unless I try to fling brass 2 lanes over. Sounds like enough reason to extract the ejector. So it should affect brass dimension for the life of the brass, right?

2.As far as f/l sizing new, it barely squeezes at all. I just do it so everything that get cut is identical after being cut. Is there harm done??

3.After neck sizing for 3 firings I have thrown only 1 case out of 30 because of run out. Do I need to check other places, or do i have to go buy a neck mic and get my measurements on new brass?

 

[Bullet bumper]

1.Okay, I. Have a plunger ejector, along with an extractor that doesn't work unless I try to fling brass 2 lanes over. Sounds like enough reason to extract the ejector. So it should affect brass dimension for the life of the brass, right?

2.As far as f/l sizing new, it barely squeezes at all. I just do it so everything that get cut is identical after being cut. Is there harm done??

3.After neck sizing for 3 firings I have thrown only 1 case out of 30 because of run out. Do I need to check other places, or do i have to go buy a neck mic and get my measurements on new brass?

The plunger ejector will cause the new brass to offset in the chamber before it is fired . Whatever offset is there will remain to some degree as one side of the case blows out more than the other .
The more you size a case down the more that offset can be.
I remove the plunger ejector in my 223 and take each case out by hand. That way the brass does not get damaged or lost . This may not be suitable for all situations so you have to work out what is best for how you shoot.
You could also have a gunsmith place a grub screw in the side of the bolt to lock back the plunger ejector during fire forming of the batch of brass. Then once they are formed the ejector can be unlocked , remove the grub screw from the bolt and carry on as normal .
There is no big harm done by sizing new brass except that if the new case fits with no problem then all you are achieving is to increase slop in the chamber .
You can't measure run out at the meplat (point ) of the bullet or on the ogive as this part of the bullet has it's own surface inequalities and wrinkles.
Bring the dial gauge back to the parallel part of the bullet or closer to the case neck. Some of the runout you measure is also case runout . You got to get that concentric fire formed case first so that later you are mainly measuring the bullet seating runout.
Bullet runout can also be a function of:--
Neck hardness consistency around the case neck .
Quality and straightness of the inside neck chamfer .
Quality and straightness of the seating die.
Suitability of the seating stem to the bullet ogive.
Skill of the reloader in seating bullets.
Design of the base of the bullet.
Surface condition of the inside of the neck.
Most of these requirements are taken care of by good dies and sensible reloading.
In a sloppy factory chamber getting a new case to fire form right in the center is hard . That is why they use tight base chambers in target guns . The chamber is already tight for a new case and may need to be sized slightly to get it in.
That way it has to be in center before it's fired .
What you can do is wrap a narrow strip of scotch tape ( about 3/16 wide ) around the base of the case just above the extractor groove . It should not overlap it's ends. Chamber it and see if it is getting tight as you close the bolt . Experiment with the number of the wraps until it is a neat fit . This then centers the case for fire forming and is only on the solid head part of the case that does not blow out with normal pressures .

I can't see that a neck Micrometer will help you in a factory chamber to any great degree . You should only be skim turning and not to any specific loaded diameter like you would in a tight neck chamber . You could use a neck mic to turn to a specific thickness of neck if you wished but that specific thickness may take off too much brass on another batch of new brass . So you would be changing it anyway.
It is simpler to just skim turn what you have in each batch off brass and don't worry about the actual thickness other than to preserve as much thickness as possible while still straightening up 70% of the neck.

 

[ajhardle]

Very interesting. Is there a book with all this information, or do have to shoot for 30 years to figure it out?

 

[Bullet bumper]

Very interesting. Is there a book with all this information, or do have to shoot for 30 years to figure it out?

By now some of this stuff is in some books but I don't know which ones .
I hear other people talk about some of it on different sites at times .
The trouble is we are in an area of applying some competition rifle techniques to our cheap ole factory rifles so there is a lot of confusion about what relates to what.
Reloading for 30 years does help a lot .
Some people say that there is no benefit to neck turning in a factory chamber . Well that depends on how you do it . I say there is if you do it right .
One of the huge problems in this game is the fact that some guns will break the rules because of slight manufacturing faults and differences so some poor person some place can't get his gun to cooperate and of course he yells the loudest on how it don't work and it's all crap .
We as gun owners have to always keep that in mind that our gun might need something a bit different than what Joe next door is doing to produce it's best but that does not mean that basic and accepted accuracy ideas are wrong .
We try things and if they don't work quite right for us , modify it and retest.
I don't talk about anything I don't use myself and I write straight from my head except that sometimes I post stuff I wrote years ago to save time but it is still my work.
If you are interested I can email some of the articles I wrote on some of this stuff . You may see some of the same documents on other forums but that is all me using other forum names .
My work on Moly coating was howled down by many for years but now I see that some US barrel makers are quoting parts of my work with slight wording changes , without recognition of course .
I could easily write a book but someone would just steal it the moment I send it to a publisher . It happened to me one time I wrote a book on GPS and Topographic map navigation but it got knocked back by the publishers I sent it to . About a year later I was in a book shop looking at a similar book put out by a Government mapping authority and low and behold I recognised many of the paragraphs and phrasing as my own book . I had been plagiarised but who has the money to sue the Government and my lawyer said that they had changed just enough of the wording to make it hard to prove but he could see that I was not imagining it . So that took the wind out of my writing sails .

 

[Bart B]

If the first chambering is an unfired case then it don't fit perfectly.

What are the details of a perfect fit? I keep hearing this but have never seen nor heard exactly what it means. As there's no such thing as a perfectly round chamber nor case and fired cases do not have the same shape and dimensions of the chamber they came out of, this "perfect fit" thing seems to be a misnomer. Please help me understand what a perfect fit means.

If it's a new case and it's been full length sized it don't fit perfectly .

Having measured neck centering errors with new cases, they all center perfectly in the chamber neck. Whatever error there is doesn't seem to matter as both new and proper full length sized cases have shot with the same sub 5/8 MOA accuracy at 1000 yards; that's as good as the long range benchresters holding records get. When Sierra's then new 155-gr. 30 caliber Palma bullet was first used in competition, top competitors from around the world said it had at least 1/2 MOA accuracy at 600 yards; not too bad with new cases, bullet runout of up to 3/1000ths, metered charges of 4895 with a 3/10ths grain spread. And in all sorts of chamber, bore and groove dimensions. 20 rounds selected at random during the handloading process two Dillon 1050 progressives loading them shot into 2.7 inches at 600 yards from a SAAMI spec chamber in a barrel screwed into an old Winchester 70 action. Even good lots of .308 Win. match ammo shot under 2/3 MOA at 600 all day long in M1 and M14 match grade service rifles.

If the gun has a plunger type ejector the case is pushed to one side before fire forming and it don't fire form concentrically and is never concentric after that .

As long as the case walls are not exactly the same thickness and have the same metalurgy, they'll never be perfectly concentric when fired. Some may well be a bit banana shaped, too, but that doesn't seem to matter much if the case head's squared up enough.

I've never heard of a plunger type ejector pushing a case to the side. Claw type extractors do that all the time, but hasn't been a detriment to accuracy. A plunger ejector's axis is parallel to the chamber axis, so it just pushes the case forward centering the case shoulder in the chamber shoulder when the bolt's closed. A case body 1/1000th inch off center in the back end of the chamber at its pressure ring will only change the bullet tip's position off center in the chamber throat about 1/3rd that much.

The skill of the re-sizer and the type of dies used also comes into it . If you study enough chambers and cases that fit them you see that after sizing some head space on ( or are closer too) the outer edge of the shoulder , some in the middle and some right at the junction of the neck and shoulder . It all depends on the match of the sizing die to the chamber and believe me not many match perfectly .

Having also measured case neck centering in chamber necks with both neck only and full length sizing dies, the full length sized cases' necks centered a bit better as close as I could read the scale. And the marks on sized case shoulders showed where they contacted the chamber shoulder from pressure from the in line ejector. When the force of the firing pin impact was enough to fire the primer, there was not only full case shoulder contact with the chamber shoulder, but the case shoulder was set back a thousandth or two. Measuring case neck centering on fired cases sized different ways also showed me that they're better centered from full length sizing. But the die's neck has to be only a couple thousandths smaller than a loaded round's neck diameter; no expander ball used.

Sierra bullets do what is normal and common so that the resulting accuracy tests a relevant to what the average shooter is doing not the precision reloader .

Sierra's first ballistic tech tried all sorts of fired case sizing dies and techniques. He was also a top notch high power rifle competitor in his own right. He chose full length sizing as it produced the best accuracy in their indoor range as well in competition through 1000 yards. Their best match bullets shot in the ones at 100 yards from rail guns used to test them.

Are you going to tell me that David Tubb does not know what he is doing .

No. I've shot enough matches with both him, and his dad, George, to know he knows he knows what he's doing. He full length sizes his cases just like his dad did and uses the same machine rest his dad had built to test his rifles and ammo in; he sells the same type of die he uses. And virtually all the others listed in the NRA high power rifle records page also use full length sized cases. Even benchresters have been moving in that direction the last few years.

 

[Bullet bumper]

You are a thread killer mate all you do is throw up arguments against everything.
If you don't like it don't do it . A guy asks for some ideas and all you can do is knock everything you don't do .
If you think that Full Length sizing is the best way to go in a bolt action then you do that , but don't try and ram it down other peoples necks .
I do something else and numerous World Champions do the same as me .
So maybe you don't know as much as you think you do.

 

[Bart B]

If you think that Full Length sizing is the best way to go in a bolt action then you do that, but don't try and ram it down other peoples necks .

I ain't ramming anything down anyone's neck. If they choose to read what I say, they do that on their own.

I do something else and numerous World Champions do the same as me .

There's probably more "world" and "USA" champions that shoot new brass, properly full length sized fired brass and even arsenal ammo than any other type from their shoulder fired rifles. I've been on international and national teams with them talking about how we reload ammo.

So maybe you don't know as much as you think you do.

On the other hand, looks like I do.