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tring to find reduced load for 30-06 using IMR 4350 or 4064 and 150gr. soft point??????? also i don"t have cronograph. using 300 win. mag. an 72grs. imr 4350 and a 165gr. nosler part. in a 26 inch barrel is there any way of estamate the velocity, FPS.????
It's really hard, as you've discovered, to find reliable data for reduced loads and jacketed bullets. Sometimes the performance - both pressure and velocity - can be erratic, so the powder and bullet companies tend to shy away from it. There are ignition problems sometimes when there is only a small amount of powder in a big case. For instance, it is often a good idea to point the muzzle straight up after chambering a reduced load to get the powder to all settle in the bottom of the case so that it burns properly. You could safely reduce 4064 and 3031 charges by 10-15% below the suggested starting loads - I have done it in both -06 and .308 without any problems, but the accuracy was not what I had hoped for. That's not necessarily an issue if you're putting together reduced loads to get a younger shooter introduced to the caliber. We're still talking "pie plate test" hunting accuracy, just not MOA for serious target work. A slip-on recoil pad can be a welcome addition, too, even for us old farts, as shooting from the bench puts the shoulder in a position where it's going to take more abuse from recoil, especially considering the amount of shooting sometimes necessary when working up loads.
Try the Hodgedon, Lyman, and Lee manuals. Another source is the Cast Boolits Forum where you can inquire of posters Waksupi and Buckshot, and others, who have a lot of experience up the road you're taking, not just with cast loads (which you might consider, too) but with jacketed also.
There is no reliable way to estimate the velocity of your loads, there are way too many variables involved: condition of your rifle bore, barrel length, bearing surface of your bullet, hardness of the the bullet jacket/degree of obduration (how it deforms to fit the rifling), powder charge, temperture, air pressure, humidity, etc... Even working with known data out of a manual, the published velocities are only a rough guide and can vary by several hundred FPS from rifle to rifle. There are relatively inexpensive chronographs available, which can give you the info you really need, though it has been said often that sooner or later you'll cough up the bucks and get an Oehler (I think I spelled it right - it's even harder to pronounce, but they are the standard by which all others are judged). I've been using a cheap Chrony for fifteen years when I really need it, but with my rifle loads I can usually get a pretty good idea of velocity by comparing the bullet drop at longer ranges to known loads. For instance, my .308 shoots a 150gr Sierra SBT at a MV of 2700 fps. (Chrono says 10shot average of 2685). Zeroed at 100yds, it drops 4" at 200yds. If I zero an experimental load at 100 and it drops, say 6" at 200, I know its MV is right around 2300.
Never go by the numbers on a box of factory ammo and think they are going to tell you anything meaningful. I think they are generally the result of some pencil pusher or bean counter whose coworkers tabbed his coffee with some kind of hallucinogen. Maybe that's not fair, but they generally read between 300-500fps higher than whatever I have found come out of my rifles and over a chrono.
Anyway, keep at it and experiment, and watch for pressure signs - reduced loads can still produce excessive pressures under certain conditions - and signs of really low pressure like dirty necks and case shoulders. When you're in unknown territory, it pays to be aware of the details.
Buy the Lee Loading Manual. It has tons of cast info and lots of good cast loads listed in a special section.
Hodgedon have a very good & informitive web site for Reloaders & a section on Youth loads which I found very informitive They recomend for reduced loads. 60% of the max recomended loads of H4895 ie: max load X 60% = reduced load this is for jacketed projectiles But I have used it on cast 150gn 30/30 with gas checks hope this helps you
Dave