load development. What's next?

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laker415

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I am working up my first reloads ever. I put 12 5 shot groups down range. Half were with 178 amax and the other was with 168 smk. I used imr4064 for all of them.

My question is where do I go from here. I have 5 or 6 groups that seem promising. I initially did .5 grain incriments but now what? Do I go in smaller incriments for the charges that seemed to work best? All groups were shot at 100 yards. Would it be wise to make enough to retest at 100 and 200 yards? 200 is as far as I can go at the moment. I just want to make the best use of time and components so any advice is appreciated. Thanks
 
Take the loads out as far as you can go and see what they do. The only reason accuracy matters at all is to make hits at long range, and short range testing doesn't prove long range results.
 
Test in smaller increments around your best group at 200yds. This will tell you if that is a good charge weight or just a flukey group.

Don't go shooting a whole load of rounds until you get a chance to shoot this load at further distances, 300yd minimum. You want to find a load with minimal vertical spread, 1/2moa or better.

My 2 cents.
 
you need to develop a system for load development, or your just chasing your tail
heres what I do and in the order I do it, I'm not saying its right but works for me in anything from .20 to 338 lapua cal guns

1) read a bit on what speed nodes are attainable and remember reloading manuals are only a guide, every gun is different depending mostly on barrel length and seating depth ( you need to be able to measure with reasonable accuracy where your lands are in relation to your seating depth )
2) pick brand of brass, bullet, powder, primer and never change them until you want to change either bullet weight or powder type
3) load 3 rnds in 3 tenth increments and jump 10 thou to start, run through chronograph to find powder charge/speed nodes and go until pressure signs show (usually tighter bolt lift) stop at first noticeable sign of that ( 3 tenth grn powder charge under that would be your max for that powder/bullet combination)
4) based on your investigation (reading up on what typically works for your bullet selection and speed nodes) load 3 rnds at 3 tenths increments from low to high and group shoot them at 300 yrds ( my experience has showed me you need reasonable distance to see an honest group form, also 5 shot groups are for showing consistency in not only your reloading ability but barrel/gun performance
5) pick top 3 groups and reload with different seating depths, seating all three different loads in and out by no more than 5 thou increments ( eg: 46.3/46.6/46.9 grns varget / 155.5 Sierra Palma bullet at 10,15,20,25,30 out to 60 thou jump ( I have a friend jumping bergers at 160 thou and killer accurate)

any time you change bullet or powder you need to redo the complete test, and you will be surprised how quickly you will find a good load ( usually in less than 50 rnds dwn range )

my 20 cents, G
 
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Thanks for the advice. I am working around my most promising groups in smaller incriments and will push them as far as my range will allow. I will admit I don't have a chronograph yet so I am probably wasting my time. It's on the list....the very long list
 
I don't think your wasting your time not having a chrony, you will find a good load playing the way you are, the real advantage of even a mid priced chrony (300.00) is when you change powder or bullets in same weight class, is you only need to attain that known velocity that your gun likes and 9 out of 10 times that different brand of bullet or powder will give you excellent results
I only shoot one round when I am doing a velocity test, I'm only looking for speed
the chrony will also explain why a certain round hit high or low depending on the velocity of that particular round in group shooting, it will also tell you the consistency of your combination by standard deviation or SD, which you want the lowest number you can attain, all though I have seen really great groups with poor SD

The other very important tool is the over all length gauge or OAL, for knowing where your seated bullet is in relation to the lands of your rifle barrel, its also a great tool for confirming your seater die is consistent, Hornady makes an affordable one that comes with inserts from .17 to .45 I think for like 45 bucks

in the end these numbers these tools give you will mean nothing to anybody else but will mean everything to the particular rifle or rifles and loads your trying to develop
 
Test charges between two or three best groups. Chronograph is totally unnecessary for load development. You can find the rifle's lands by seating a bullet long in a partially sized case and chambering. Doing that will either push bullet deeper or make marks on bullet. Check your seating plug, make sure its not seating bullet with pressure on tip, should be seating with bullet supported on "ogive". Powder and bullet selection are fine for your 308. The SMK 168 is not a long range bullet, you'll have better results with SMK 175.
 
Chinbullco is correct, the 168 is primarily for less than 700yards (it slows around 600-700yards out) the 175 is good to 1000 yards (starts to slow drastically at 1000 yards). I have heard of guys shooting 155 with a velocity of 3100fps (a fine tuned load) out to 1000+ yards accurately. Once again this will all come with playing with the powder loads, O.A.L. and how your lead chucker reacts to the loads.


What I mean by slows down is that it loses its stability and will start to "flutter" which will cause it to become inaccurate.
 
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