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Originally posted by rcamulia:

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See, everyone one was right!

Koom-buy-ya!

Still wondering where you found the biographical video of a few of the members!

'tinternet Rick, the source of all good things....

I have owned and shot seven different .375H&H rifles since buying my first in 1982 and I currently own two custom P-64's so chambered. I have shot thousands of handloads from these rifles and they were all custom-epoxy bedded and tuned by pro 'smiths.

The legendary American gunscribe, Jack O'Connor, often wrote that the .375 was a wonderful round in that it would place bullets of different weights to the same p.o.i. and, of course, he was referring to "hunting ranges" of his era, which were about 400 yds and less.

I much prefer a .338 bore to the .375 and have shot gazillions of bullets from rifles so chambered. I have found that, for example, my Ralf Martini customized Dakota 76 with the Shilen bbl. will put all bullets into a small group at shorter distances, certainly enough for BC hunting. However, I have yet to see a rifle, of the roughly 125 big game rifles I have now owned or the scores that I have helped sight-in and loaded for that will always put ALL bullet weights to the same poi at extended ranges.

I am not sufficiently computer literate to know if a programme exists that WILL give the info. that the OP wishes to have, however, with over 53 years of shooting rifles and some small groups at 500 yds. with my first and most beloved P-64-.338WM, I will also suggest that the best method of finding what YOUR rifle and load will actually do is to shoot it extensively with the loads you wish to use and see what happens.

Besides, the more we shoot, the better we shoot, IMHO.

There won't be any way around fireing the different loads, and possibly play a bit. A program won't be able to predict the inital point of impact, but could be used to track trajectory from that point out.

On my own .375s I know that my 270 grain loads print about 3 inches higher than the 300s at 100 yards. That state of affairs means that when the rifle is sighted in for 100 yards with the 300s it is also zeroed at 200 with the 270s. That could be put to use if I wanted to poke around in the bush with 300s, then swap to lighter bullets for the plains. The trouble with that is that the 300s fly nearly as flat as the 270s, while the 270s seem to clobber big animals just fine. At least the 9 buffalo that I shot with 270 grain A-Frames all seemed to die in the approved fashion. What then in the advantage of switching bad and forth?

The lighter 235 grain range bullets are fast out of the gate, but at longer ranges the seeming trajectory advantage disappears.

You could pick a premium 270 grain bullet and use for everything than doesn't require a solid and be well served. That's where I ended up.

Thank you all guys.

I bought few packs of Norma ammunition loaded with 300gr Oryx bullets, I have also some Federal with 260gr Accubond and Sax Ammunition loaded fast with 10g (~154grain) pure copper bullets. Will take to 100m and 300m range soon and will see. When tried with old scope, it looked that 260 and 300grain at about 100m or yards are going very closely, but 154gr sax was going about 15" higher!

Will post report soon.

Jiri

All that follows requires that you know what the hell you are doing behind the trigger otherwise, you might as well be peeing into the wind!

Well I was not going to get involved here but let me tell you the way it works. First you need to determine your velocity for the two bullets being tested and check the POI at the same time. The reason you have to check POI is because to make the assumption that one bullet being heavier is just going to have a different vertical impact is flawed and cannot be used without first base lining the data. So at 300 yards the 2nd load shoots 6.5 avg lower than the first as well as 1.9 inches to the left. This is your Base Line---you had 20 rounds (10 of each bullet) starting with a clean barrel and using the same aiming point you fired alternating rounds to minimize and effect condition or temp would have on the groups. Now you have 2 different groups take the average of the vertical and horizontal movement of the base line and apply it to the information derived from the software generating your ballistic charts. The actual horizontal change to the second load can be input as an actual value at 300 let’s say and your chart will tell you how far you must correct for at any distance. You can do this by inputting a wind value that would correspond to the actual movement of the second load and it will give you the correct horizontal adjustment.

Now that was easy wasn’t it…

What's even easier is to pick one load and shoot it

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Originally posted by rcamulia:
What's even easier is to pick one load and shoot it

Hell yes----that is what I do now. Fortunately for me most of the time I know if I need the long range gun or a short range one when I go out. When in doubt take the long range one--better to not need it and have it than need it and not have it.