[slangley]

I need help with developing a light load.  I am using a steyr scout in .308 win.  I want to raise/lower the impact of a small game load to meet the point of aim on my scope at about 30yds.  The scope is pre-adjusted for my big game load and I don't want to change it.  Which change in powder load (heavier/lighter) will move the point of impact which way (higher/lower)?

 

[Charlie Z]

There's an article in the 1996 Handloader's Digest about Whelen's light loads for the 30-06 that may be helpful.  Apparently, Whelen did it by trial and error...

If you can guesstimate the right .308 powder off of the one he recommended for the '06 (or even use the same?) you have a start.  Bullets should be the same.

Whelen's 30-06 small game load:

18grs IMR 4759 behind a 150gr FMJ (1500fps) or Lyman #311466 (1600fps).

(He also shot a grizzly 3x, accidently using the grouse load.  That would provide a lot of surprise for everyone involved.)

An option the article also suggests is that you just mentally mark where on your crosshairs (thick post, etc.) the small loads strike in relation to your normal load.

Charlie

 

[Charlie Z]

PS:  Sighted in 3" high @ 100yds with his normal 165gr hunting load, Whelen's small game load hit 1.5" low @ 25yds, 2.5" @ 50yds and 4" & 6" low at 75 and 100yds.

He was using a 22" Remington bolt gun and was getting 1568fps with the cast and 1537fps with the FMJ.

So, if you can match that velocity with the load you work up, you may have a start.

 

[thebulletcaster]

Slangly
  If you would get a copy of Richard Lee'sMODERN RELOADING,and turn to page 91 ,you willfind what you are looking for.On page 92 there is an example of how to use his method
  Now ,I dont know if you are familiar with the concept of  the 1000-in sighting in range,but here it is.1000-inches is equal to 27.78 (that is pretty close to 30yds.)yards.When sighhting in most  high -powered rifles, when you sight them in at 27.78 yds. they will be pretty well sighted for 100 yds.So, get Lee's b
ook,orborrow one ,work up a load and sight in at 27.78yds and you are in business!(In fact, you could sight in at 25 yds and still be "close enough for missle work")    tbc

 

[Alk8944]

This is an interesting question, and one I have been asked several times.  There is only one answer, and Charlie Z hit it on the head in his first paragraph.  Trial and error.  There are too many variables in firearms to make any generalizations, a change in load which results in a lower Point Of Impact (POI) in one rifle may cause another to shoot higher, left, right or any possible combination.  The left or right correction by changing load is really a challenge.

Even if you get a load to shoot to the same POI as your sight adjustment for a full power load it will only be correct at one specific range.

 

[slangley]

Thank you for your help, gentlemen.