Reloading for Precision shooting?

This is all about the 223Rem loading for target shooting 100-300yards.

Up until recently I had been using a Lyman Headspace gauge to set my sizing die and it was doing OK. I recently bought a Hornady comparator to use on my digital caliper. Have now been using it to set my seating depth as until recently all my brass had already been resized.

This time around I had2 boxes of empties that I just shot so I measured them with the comparator and one box measured 1.461" and the other measured 1.162 then also measured a group from my bucket and they too were 1.462" so I decided to use 1.460 as my headspace setback..

As I moved through all this brass my measurements kept moving when I checked lengths from 1.4605" down to 1.4580 So I started checking more before sizing and found more of the 1.461 and even some 1.460.. Now all 260pcs. of this brass has been fired in this gun. Showing a .002' variance. Is that normal?

Also I segregated the 1.458 from the 1.460" sized brass. Do I need to do this? Will that much variance effect accuracy? Cause fliers or other anomalies?

 

Yes just like seating depth there will be variation. The amount of spring back in the brass causes the variation. This is the reason people get crazy about annealing. You had the same variation before, just never had a way to measure. Try your new sizing and measuring for a while and then see if you need even more control.
Shoot the brass together I doubt you will see any difference

 

Right now I have 100 pcs sizes to 1.460 and about 30 @ 1.458 and 10 at 1.459..Was intending to shoot them together in groups just for my own experience.

 

The very top guys test every consevable angle. It's my theory that a good node eats up the small differences. Two thow is not bad variation.

 

Suppose that would be my next question, so what tolerance do all the precision shooters try and hold?

 

Yeah expect 2 to 3 thousands on brass that hasn't been annealed.
If you anneal just right it will be more like 1 thousands.
Getting real crazy for neck tension and shoulder consistency that's for like 500 to 800 yard shooting or more.
Finding an accurate load is more important than all that stuff.

 

Well trying to do the best I can with what I've got. To control that which I can w/o investing a Kings ransom.

The brass is Norma which has already been fired in this gun at least twice. Haven't been able to find Lapua or Peterson w/o paying $1.25 ea or better. The barrel is a Savage Model 12 Varmint that was a new take-off when I got it. Bullets are Nosler 69gr Competition. So far the best powder I have found are Benchmark and 2460. It is more capable then I currently am.

 

If your trying to control the outcome to the maximum extent, sort them in your box from max to min. Then your progression from low to high is steady and progressive but not random. The problem becomes that when you stack factors your groups become smaller and smaller. Then you move to sorting base to ojive on bullets and weighing primers. Run the test and verify it does or doesn't matter. I'm betting it doesn't. If you included bullet run-out in your group sorting each round would be in its own group. I would treat it the same as run out, less than .003 just move on.

 

I started chasing everything I could. I found most of it doesn't really matter. Except annealing and neck turning cheap brass. I didn't go crazy on the turning. Just enough to clean most of it. Then I scrapped the worst if it. Based off the uneven neck thickness.
I tried Lapua brass and got the same results I did with all the work done at the factory. I figure the amount of money dictates the better route.
The best accuracy I've been able to maintain was 1/2 moa @400.
Before doing that work. I struggled to hold 3/4 moa. My varmint guns are worth it. My deer rifles I've decided it's not worth the hassle.

 

Can say that from some friends I have seen the bullet seating depth makes a difference in top of the line barrel. I my factory Savage not so much. Though I did also learn that annealing did make a difference, groups became much more consistent. Even primer seating made a difference in consistency. Also found that changing a $3.00 trigger spring made a huge difference.

 

I started this adventure 2.5 years ago with a Savage Axis in 223. I then moved to a used Savage Model 10 223 and learned much and acquired some valuable trigger time.. Enough to know I needed a better rifle. Another season on the league and I will be ready to move on again to a good aftermarket barrel. Can now shoot pretty consistent 3/4 MOA at 100, Sub MOA at 200 and just over MOA at 300 yards. I am happy with my progression.

 

That's not bad at all considering 223 gets moved relatively easily by wind. I call MOA with mine good.
My best work has been with a 22-250. My Axis would group~2"@300. When I moved to a 26" Shilen barrel. I could consistent get 2"@400. But I changed twist rate and moved to heavier bullets as well.

 

Was all this brass the same brand and from the same lot number?
Different brands of brass and even different lots of brass from the same brand can have very different case volumes due to different wall thickness and web thickness.

This is why for my precision shooting I buy Lapua brass and even then I buy several hundred with the same lot number and keep it segregated from other lots. If we are talking about .308 brass weight from lightest to heaviest is less than 1grain difference.

If you want to test internal case volume zero your scale with a piece of brass which has a fired primer on it. Then fill the case with water ensuring that it ends perfectly flush with the neck and weigh the amount of water in the case. This will give you the weight in grains of water of the internal case volume.
Compare different cases and you will start going down the rabbit hole of precision.

 

Yes it's normal, yes it will effect accuracy. . . but let's put some context on it.

There is no "all precision shooters". Benchrest shooters shave their flea's gnat's whiskers and win or lose on 0.01 MOA. High Power shooters use carefully bulk-loaded (not rifle specific) ammo. PRS matches have been won with factory ammo.

The right question is whether or not this imprecision is discernable in your rifle, in your hands. I say: No, not unless you're already shooting below 0.5MOA. The last 0.001 sizing matters very, very little to precision.

 

Same headstamp/lot?

 

And THAT's exactly why I don't shoot competitively.... I couldn't even *measure* .01 MOA, much less shoot it!!!

 

I dabble in long range precision shooting and for my stuff it takes more than one or two firings to fully fire form brass, until then I will see slight in consistencies in length while I continue to monitor brass. I don’t get to axle wrapped on set back until I start getting resistance while opening ( and closing ) the bolt after ignition. As for annealing, I’ll leave that for the experts.

On a side note calipers and a comparator can be manipulated by hand pressure to read what you want.

 

AJ is exactly right, we test the test!
I can get away with a lot of stuff while shooting at 600 yard, now move that target to one thousand and everything you once thought true needs to be reviewed.

 

Thanks, that is the perspective I was hoping to receive and makes much sense..

In post #8 I did finally comment that all this brass is all Norma though it is not all the same lot. It has also been shot in this rifle twice and has also been annealed twice. Over a year ago I ran an unscientific test on 5 different headstamps and found the Norma heads above the rest and unbelievably the PMC was right there along with it. Also gave the water volume measurement a try but gave up after I did not find any great variation in the random brass I had.

While my shooting ability has vastly improved I honestly doubt I can shoot the difference right now. But the procedure doesn't cost anything but time. So will it help eliminate some of the errant shots, the unexplainable fliers? As mentioned hear I guess I will have to try it for myself. So from what I am gleaning from the responses so far is that .002 is not abnormal and will most likely be indiscernible and I can accept that perspective.

So just for this one reloading session I will continue to separate these and try shooting them for myself. Still learning and still improving!

 

Jim I know you do and was hoping you would be one of the respondents. Along with Walkalong. I have now heard from both of you.
We have chatted previously on the merits of annealing. Again in my case I did see an improvement.
Fully aware of the hand pressure and try mt best to keep it even and consistent. I do try my best to get the brass to sit flat.

 

You may want to run your cases past a chronograph and pull out those displaying a large difference in fps, sorting by performance vs volume has really helped my little program.

 

And here I thought my extreme ES was from my reloading practices.

 

Great thread I’ll enjoy following along very much

 

I would only add, learn to read the conditions. It’s too easy to get lost in the minutiae of loading only to get schooled by the shooter who can read and shoot in the conditions on the range.