Med-Long Range Load Development How-To's

[augustinaustin]

Med-Long Range Load Development How-To\'s

Rifle is a Gre-tan built tight-neck 300 Ultra, Nesika action, Jewel, Kreiger 30", Nightforce bases and Scope.
This gun was shooting one hole throughout break-in and fireforming. Last group was .4 in diam. I am now doing load development with (5) different loads. My local range maxes out at 200yds. I have to drive 4hrs to shoot further.

QUESTION: If my immediate goal is becoming very competant at 500yds will the loads that group the best at 200 likely be the ones that group the best at 500?

 

[Boyd Heaton]

Re: Med-Long Range Load Development How-To\'s

Maybe,or maybe not.......I have two 300 Ultra's that I shoot 1000 yard benchrest with.I would say your 200 yard load should work well at 500 yard's.....Let me know how you make out.......I am interested in your finding's.....

 

[Mysticplayer]

Re: Med-Long Range Load Development How-To\'s

You can try and back up your group size with chronograph data. Small groups and small variations in vel indicate an excellent long range load. That is how I do my load development too.

However, I will always shoot at long range to verify because short range shooting can not show you any stringing that may be occuring. This stringing can make your groups huge at long range. Also temp. variations can affect your long range performance.

I am now using Hodgdon Extreme powders for my hunting loads because of their stability during temp. changes. They usually burn very well too. H4350 and H4831SC are what I use now.

For my 300RUM, I will be using H870 to start. This is supposed to not be temp. sensitive. However, I have never found a ball powder that wasn't. WCC 872 is also a great surplus powder. If you are building your loads in the cooler months, back off when shooting in the summer.

Good luck..

Jerry

 

[Mysticplayer]

Re: Med-Long Range Load Development How-To\'s

If the actual BC of the bullet in flight agrees with the bullet manufacturer, then the computer generated drop table will work.

I have had only one rifle and load that did that. All others varied significantly enough that I had to make my own from actual shooting. The only thing the table did was get me in the ballpark to allow for adjustment.

I have also found that poly tipped bullets fly flatter then hollowpoint even though their published BC were very close (same rifle with very similar muzzle vel). Would like to hear if others are experiencing the same thing.

Good luck...

Jerry

 

[augustinaustin]

Re: Med-Long Range Load Development How-To\'s

Thank you for the info. I got out to the range again this morning and the load that had the smallest deviation did turn out to be my smallest 100yd group. I have not used any Hogden powders yet. I have always had really good results from RL25 but I know it sure changes in 100 degree weather.
I know you must always try a given load at your intended range but based on your experience do you find computer generated drop charts out to 500yds to be relatively accurate IF:
1) the real bc is plugged in
2) the load gives good accuracy and small velocity deviation at 100yds

assuming that correct (and similar) temp, baro. etc are plugged in as well