What is everyones procedure for finding a load for a new projectile

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saltbait

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Hey guys,

Wondering what everyones process is for testing loads for new projectiles in there rifles.
I am concerned that I am going through too many rounds for testing.
Mine currently involves :

1st range trip: 100 yard testing
- Look at reloading manual and go up 0.5gr from recommended until reaching recommended max.
- Load 10 rounds for 0.5gr from min to max.
- warm up barrel with factory ammo and shoot 2x 5 round groupings for each 0.5gr.
- narrow what grains of powder to test next range trip by choosing most accurate groupings.

2nd Range Trip 100 yard testing
- Load 5 rounds for each 0.5 gr (narrow range of charges....first time might have been 38 grains to 43 grains....this time it could be 41.5 grain to 43 grain).
- Warm up barrel with factory ammo
- Further narrow range of charges (usually I can get it to within 1 grain after the 2nd range trip)

3rd Range Trip 100 yard testing
- Once specific charge has been found I will start to play with COAL.
- I'll start about 0.01 closer to the lands than what the manufacturer suggests and work my way back 0.05.
- I'll shoot 3-5 rounds for each different COAL.

Feel free to tear apart my process, but don't just criticize... tell me how I can make the process better!

Thanks
Ben
 
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I use the Dan Newberry OCW method. Sometimes I will perform a similar round-robin test for seating depth (I have been advised that sometimes it can be better to just skip that step).

I have successfully identified an OCW accuracy node one day and made 1000m hits with the new load on the next. I have played with Audette style ladder testing and have not found much value in it for my purposes to date.

I started a thread about my .223 load development some time ago that you can check out. My most recent tests have turned out better with less effort than I was putting in at that time.
 
Load 1 round from mid range to 2 or 3 gr over max listed. Shoot a ladder at 300m. Shooting until I get pressure signs. Analyze and load for some groups. Then seating depth.
 
I tried the OCW test for the first time this summer. I got a real nice load out of it. It will be the way I do it next time as well.
 
hometownhero said:
Load 1 round from mid range to 2 or 3 gr over max listed. Shoot a ladder at 300m. Shooting until I get pressure signs. Analyze and load for some groups. Then seating depth.
Click to expand...

I do something similar , I go from lowest published to above highest published , stopping at pressure signs and load increments vary with case capacity.

Then, depending on the application and rifle I will prove or tune at 100, 300 or 500.

Sometimes after a ladder test and a 3 shot group I can settle on a load.

If I am looking to have a precision load I shoot 5 shots groups mainly and play with other factors.This in itself can be an endless process if one allows as you should only change one variable at a time.

I have pretty much abandon shooting groups for an initial test.A 10(ish) shot ladder can tell me what I need to know instead of wasting 30 or 50 rounds initially.
 
1) Look up load data in reloading manual, also internet search for what everyone is using.
2) First Ladder test.
- fairly board charge range.
-OAL 10thou jump off lands
223 sized case = .2gr increments
308 sized cases = .3gr increments.
338 sized = .5gr increments.
-2x rounds at each charge.
-all rounds shot low to high at 300 or preferably 500m.
-use high quality glass or target camera to record each round with its hole.
-shot fairly slowly to avoid heating barrel.
-BIG piece of paper as target. No scope adjustments after I start.
-use buddies labradar if available, don't use magnetospeed.

3) Second Ladder test(s)
based on results of first ladder, smaller range and finer increments around possible nodes of least vertical/lowest velocity increases
-exact same procedure as first ladder
-might skip this if first Ladder test has really good results.

4) Group confirmation
-shoot 2-3 groups based on second ladder results. 300 or preferably 500m.

5) 100m zero
-zero for best load at 100m, chrony muzzle velocity for ballistic calc input.

6) tweak with seating depth if I feel like it. If I'm using VLDs, I'll do Bergers test before first ladder.
 
I'm loading a few Nosler Accubonds for the 6.5cm....I may buy some accubonds for the 308 as well and try out the ladder and ocw tests.....do the ladder test on the 6.5cm and the ocw on the 308. From a bit of research I can tell that both tests have pros and cons. I am definitely going to redesign how I am testing loads as I am going through a lot of components when load testing.
Great advice peeps! Thanks!

Ben
 
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I"m doing much like you Saltbait, except that I tend to shoot 10-rounds groups for the second and third tests. I shoot pistol calibers at 100m (9mm, .357mag) so it's more affordable in the first place.
 
My method mimics Apheus' almost exactly, with a few minor differences:

First string is shot low to high (watching pressure signs progression)

Second string is shot high to low (from top end charge established by the low to high string). My theory behing the second 'reverse' string is to reduce (or maybe just identify) possible barrel heat effects that may have factored into the first string.

I use my chronograph for each shot in development. Often, it helps to interpret the results as printed on the target.

Rooster
 
Research has helped me more than anything - most calibers have loads that just 'shoot', in many rifles - i then load under these and go up to the common loads and then see what happens, obviously watching for pressure signs.
I usually do 3 shot groups, 0.3gr apart, then once a promising load is found, then go down to 0.1gr. Start all at 20thou off rifling. Once i have found repeatable, then tweak seat depths to see if they make a diff.

Some common loads that seem to be very close to nodes in most rifles are:
44ish gr Varget 175smk in 308
42ish 4064 " " "
42.3 gr H4350 in a 260 with 130's
30gr Varget in 6mmBR with 105's
24.5gr Varget in 223 with 69 smk's
There are many more, but these are what I have used as my benchmark. These I compare to manuals I have to make sure I am not way off base.
 
What I do is :

Model a load on Quickload with the components I want to use and what ever COL I want, two choices here, magazine length minus 0.010-0.020" short or if single loading 0.010-0.015" off the lands. Enter all pertinent data into the QL program as accurately possible.

Refer to Optimum Barrel Time (OBT) chart to zero in on a node that has acceptable pressure, charge case to that node, at the same time look at the compatibility of the powder to the rest of components your using, if Optimum Charge Weight (OCW) can not be achieved then I'll look at another powder or another bullet. The result will be a predicted velocity.

Once I'm satisfied with the model 5 rounds are loaded, to fired out of a barrel with several rounds on it since cleaning . With the LabRadar set up I'll shoot a 5 shot group, either 109yds or 219yds (100 or 200m) depending on which range I'm at (we have two, one out to 1000m and one at 200m).

With the 5 shots the velocity is particularly important (generally its what the 5 loads are about), needs to be low ES and close to the QL predicted velocity. Also, the group is checked for 'shape' whether it strings vertically , horizontally or random.

With the recorded velocities I go back to the QL model and adjust parameters in the program, this generally is adjusting the burn rate (Ba) of the powder. After this I will have a predicted velocity that mirrors real world performance.

The new load which I load 10 rounds for ( confidence level is high, due to practicing this method for quite a while), shoot a 5 shot group at 200m and another 5 shot at 3-500m depending on conditions.

The above is usually the best the platform can produce.

So some key items, QuickLoad is basically what a calculator to do the math easily, the operator must understand the principles of internal ballistics to operate well. Accurate velocities are paramount, with out that, no calculations work as they should. Handloads must be mechanically perfect as possible, powder weights down to 0.02gn (FX 120i), concentricity, as close to 0.00" run out, no variance in COL and basically what Jerry has stated in his article (great article BTW).

This method has uncovered a few things that have detracted from small groups, rifle bedding, optics, methods off mounting optics (correct torque on fasteners and de-grease everything) and the big one operator error aka bench technique.

The rabbit hole is a lot deeper than I have imagined!
 
I pretty well do as BCBRAD does, the only difference is I will first find what the max load is with the components I'm using , then use Quickload to see if I can reach an acceptable nod. I work up in 1 gr increments till I feel i'm close then drop to .5 gr increments. Some times I can go 2 or 3 grs past the manual max load and sometimes I can't reach their max.
 
thenerdboy said:
Personally, I would never load 2-3 grains over published max. I assume he means 0.2 to 0.3gn over max (tenths of a grain).
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No. I meant what I typed. The max in the book was the max for their rifle not mine or with the lot of components I am using. I even have some loads that there is zero data for. For those look at burn rate charts and start low and work up.


You can load as high as you want doesn't mean you have to shoot them.

hunters home said:
Some times I can go 2 or 3 grs past the manual max load and sometimes I can't reach their max.
Click to expand...

My findings as well.
 
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Tagged.

Mystic's method's worked well for me. No reason to change but for my own curiosity to experience ladder tests and see if I can arrive at the same accuracy differently.

Regards
Ronr
 
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