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subsonic
06-26-2009, 10:15 AM
When you work up a handload with new stuff, how do you go about it?

The way I do it is load a handfull of cartridges, each with an increasing powder charge up to and sometimes over max, and shoot them over the chrono. Start at the highest safe load and work backward shooting 5 shot groups til I'm happy.

I'm looking at OCW stuff and not really convinced....

Nelsdou
06-26-2009, 10:08 PM
Sub,

If it is a cartridge totally new to me (and gun) I do quite a bit of homework using Hornady/Lyman/Ken Waters data and running gun-specific (like barrel length) numbers in QuickLoad for a general validation. Then picking a reasonable bullet seating depth based on the barrel throat configuration, load incremental set of charges, five each (if I'm pressed for time, three). I try to do the load test like suggested by :

http://www.desertsharpshooters.com/manuals/incredload.pdf

If I have a barrel "node" in the range of my testing I make a note of it if it "shows". If not I don't lose any sleep over it, just as long as I obtain a load that shows some marked convergence to a tight group somewhere along the way. I don't push the load any higher if the gun or brass start showing any indication of high pressure.

Nels

gitano
06-28-2009, 08:54 PM
My procedures are pretty close to Nels'.

I happen to think that the Optimal Barrel Timing theory is the 'real deal', IF one keeps one's eyes open to the possibility that some variable specific to the rifle in hand may skew the results.

As for OCW, I subscribe religiously to the process. The fundamental point being that a tight group at some charge doesn't necessarily make that the "best" charge when variations in hunting conditions - like large swings in ambient temperature, or big changes in elevation - are considered. Rather, the chargeS that produce the least change in group size AND POI are the charges that will keep the bullet where you point it regardless of changes in ambient conditions.

In retrospect, the OCW concept has been proven over and over again. Ken Water's Pet Loads is just one of the 'proofs of the pudding'.

Paul

M1Garand
07-06-2009, 09:04 AM
I too like the OCW method and have been shifting towards it myself. Check out Dan Newberry's site:

http://optimalchargeweight.embarqspace.com/

sakorick
07-07-2009, 08:47 AM
I'm not nearly as sophisticated as Nels and Paul, however, I do have and for the most part stick to my plan. My goal is accuracy first and speed 2d. For a new untested and untried rifle, I start with the Sierra middle of the road load with the most favored bullet weight for deer hunting.....for instance a 7MM Mauser 140 gr bullet would be my starting load, 150 for 30 cal, 150 for 8mm, 120 for 6.5, 115 for .25 and 95 for 243. Then I carefully measure the OAL and start 25 thousandths off the lands. Prior to firing, I mount the scope and boresight with my laserlite....this saves wasting test bullets as I am always on paper at 100 yards. First two go thru the chrony then I fire a 100 yard three shot group and mark. Then a 3 shot group with one grain more powder and mark at the same time adjusting the scope on bullseye. If it's a new barrel at this point I clean the barrel up one grain, chrony and repeat. I do this until I reach 1 grain of max load and drop back to .3 grain increments to max. After 25 shots I drop the cleaning to 25 shot intervals.

I then pick the best group and start playing with the OAL going first down(longer) to 5 thousandths in 5 thousandths increments. If the groups get worse, I start at 30 and go shorter 5 thousandths at a time and quit at 50. If I'm not MOA or better by then I start over with a heavier or lighter bullet depending on the twist.

For tried and true calibers and Milsurps I just start at a known favorite load and go from there. I think the most important thing to remember is to take good notes regardless of how you go about your load development. Regards, Rick.

Sidebar. I always use flat base Sierra pro hunters for load development.....always. For my ultra long shooters like the 6.5-'06 AI, I switch to Noslers BT's when I know I'm close.