How do you OCD reloaders get your ES and SD down

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mooger31

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My wife got me a magnetospeed chronograph for Christmas and I got to use it today. The chronograph worked perfect, but I noticed that my ES and SD were higher than I wanted. So I'm hoping to get some help or hints on how to get them down. Here's how I load and what equipment I'm using. So for the most part I'm neck sizing using lee collet dies. I try to make sure I keep gettin the same neck tension (I'm using a rcbs rock chucker). Then I trim if needed with a rcbs trimmer, use a flash hole and primer procket uniforming tools, then chamfer inside and out, and then use a cleaning brush. I then prime the cases using the lee hand held priming tool ( I use cci 200 and 250 primers depending on caliber). After priming is done then I measure out powder using the rcbs charge master and to make sure all powder is equal I make sure it is exact on the rcbs 5-0-5 scale. Then I install the bullet using lee bullet seating dies.

So where in my reloading methods could I get lower Sd's and ES? Or are there some other equipment that I should get to help me?
 
Care less about velocity difference and more about accuracy. Chrono's aren't very accurate. (not sure about this model). If the rifle is accurate then that's the key.

Can't help with the rest
 
What is the extreme spread and standard deviation that you recorded and how many rounds used to calculate? Most obvious suggestion that you could try is match primers: CCI BR, Federal GM.

My setup isn't much different: I have verified the charge master and don't bother often as it is pretty good. I neck size whenever possible and the two calibers I reload with intentional OCD I have Redding and RCBS dies. Most of my best groups have been with a 6.5X55 and prime the Lapua brass with BR2 primers. I wrote the chronograph figures somewhere... and would present them for comparison.

Your groups will be what matters most, and you might be surprised the "expanse" that normally exists in SD and ES. Rough recollection from memory, ES with a pet load for the 6.5 which groups under half an inch at 100m, maybe 80-100fps. I may have remembered incorrectly and I don't remember SD at all for that load.
 
Try quality brass, higher neck tension (That might involve parking that collet die) match primers and loading hotter. Especially the last one. The .308 has a long match history with some powders that stand out. Use one of them.

You can get great 100 yard groups with ammo that varies wildly in velocity. Some will look at that as evidence that spread doesn't matter, where it is actually proof that 100 yard groups don't mean much.
 
Dogleg said:
Try quality brass, higher neck tension (That might involve parking that collet die) match primers and loading hotter. Especially the last one. The .308 has a long match history with some powders that stand out. Use one of them.

You can get great 100 yard groups with ammo that varies wildly in velocity. Some will look at that as evidence that spread doesn't matter, where it is actually proof that 100 yard groups don't mean much.
Click to expand...

This!
Plus you may be loading a bit "light" for the bullet you are using. Stepping up just a bit can sometimes take a 100 fps spread down into low double digits.
You also may want to try a different powder.
The high number spreads really start to show up at 300+ meters with vertical spreads.
Regards, Dave.
 
As stated, try match primers and either sort your cases by weight or buy some good stuff. Lapua .308 brass isn't much more than bulk brass but it is so much better. Lastly unless you're using hunting bullets then your seating depths are probably varying quite a bit. My Lee DL seater in .308 would not work with match bullets. It turns out they use the same seating plug for a whole bunch of seating dies. Match bullets will be seated way too far up the bullet to get consistent seating depths when measured off the ogive. Lee can make custom seating plugs for cheap but they stopped taking new orders for their custom shop to finish months of backlog. I bought a Forster BR die and get seating depths within less than .001" variance.
 
The powder I'm using is rl-15 and my load is 44.7 gr. this load is giving me sub moa results in a tikka tactical. And the bullet is a 168 silver ballistic tip. Don't have many of those left and then I'm going to 165 gr accubond.
 
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I looked at this thread yesterday when it was just starting and my first thought was too light a charge of powder.
Now, I look and Dave has already told him that!
The most famous bench rest and long range shooter of all time was, without doubt, Warren Page. In his book, The Accurate Rifle, here is what he says about loading the 308.


And here is what he says about loading the other big ones.
 
I would try the lee taper crimp die and then a different powder. I've always ha better results when the shell are loaded close to max. Imr 4064 has been good for me. Varget also
 
Is my chrono screwy? I match my brass by weight and volume, neck sized and annealed. Filled with 79.5gr of h-1000, 210 Berger vld's, and cci 250 primers in my .300 win mag. My chrono has displayed es's with this load from 13fps to 43fps and sd's in the 13, 16 fps and as low as 3 and 4 fps. Can this be true? I rarely get out far enough to confirm this on paper, plus I rarely shoot paper anyways, usually random objects at random ranges. However last time I shot paper was 3/4"ish vertical spread at 395y. This is a good indicator but I just don't shoot paper enough to have a solid reference. These numbers are to the best of my recollection. I had notes saved but I can't find them, must have deleted them.
 
mooger31 said:
Sorry, should of put that in there. My .308 had a extreme spread of 137 and standard deviation of 78 ft/sec.

I would like to get it as low as possible.
Click to expand...

I tested both the Magneto speed and a Shooting Chrony using them simultaneously and they were both very consistent with each other; the Chrony was always giving 30 FPS faster (measuring velocities of about 3000 FPS). The difference in velocity between the 2 instruments may be well associated with the fact that the Magneto measures at the exit of the barrel versus the shooting Chrony measures at 8-10 ft from the barrel. So I think both chronographs work great and they give very accurate results. I always use the chronograph when developing loads and I would associate good accuracy with low velocity spreads. I would suggest that a good accurate loads should have a total spread of 30-40 FPS maximum.

BUT you can't automatically associate very small spreads to good accuracy; certain bullet will like a certain velocity range. For instance, you may have 200+ FPS difference from the minimum to the maximum specified powder charge, that powder may give very consistent velocities but somewhere between that minimum to maximum charge you'll have better accuracy.

Like many said, good quality components is the key. Buy Lapua or Nosler brass. In my 308, I always use CCI Bench Rest primers and Hodgdon Varget. For punching paper, the 168 Sierra Matchking or the 168 Nosler Competition bullets with 43.0 GR of Varget has always worked great for me. For hunting, I use the Berger 168 Hunting VLD's.
 
Some cheap chronographs are not all that accurate, also how close to the muzzle are you shooting, the chronograph will read muzzle blast , mine is about 10 ft or more out, sd doesnt matter to me when loading accuracy much but just tells how well ive loaded each consistent, i full length size mine, clean primer pockets, measure every case length and trim within .001, usually about .015" under max, measure each charge 3 times to make sure its correct, set up and seat the bullet within .001" either way off the ogive.
 
Also, es and sd are your long range indicators. A 50fps spread at 1,000 yards will be a lot of vertical stringing. The shorter the range, the less it matters
 
"...where in my reloading methods..." There's far more involved than just how you load. Those stats don't mean squat if the load isn't accurate either. What bullet, etc?
 
I'm sorry for not getting all the information in the first post, but if you check all my following posts I think I got all componets and equipment that I'm using.

I was thinking of buying a micrometer forster or redding seating dies and neck sizing dies so I can control my neck tension and seating depth better as well as a concentricity gauge as well. But before I bought those peices I wanted to know how much more these items would actually help with getting a more precise load and help get es and sd down.
 
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