First Time Ladder Testing - 260 rem

With my new 260 I decided to try something different with working up a good load. My method to date has involved loading up 4 or 5 loads per powder charge with increments of 0.5gr ,starting about 1/3 of a way up between book min and max and then shooting groups, going with whatever gets the tightest and then finetuning from there. That method has worked well for me to date, but can be a fairly long process.

This time I thought I'd try a ladder test, shot at around 285m - image below

Loads 1-6 ranged from 37.5 grains 40gr of 2208 with a 120gn ELD-M. I shot the loads 1 through 6, and then shot the same over a chronograph - Velocities seemed reasonable out of a 21.5in barrel

Velocities

1- 2751
2- 2759
3- 2808
4- 2845
5- 2878
6- 2923

With no real cluster of groups can anything be interpreted from this??....Velocities were around what I was after around loads 4 and 5 so I was going to load up a few more of those charge weights and see what groups look like. Any other interpretations would be appreciated...

http://i933.photobucket.com/albums/a...1/IMG_2874.jpg

I'd try No 4. Big jump between 2&3 and between 5&6 so go with the middle of 3,4,5.

OK thanks stug, I thought as much, but wasn't too confident as I hadn't done this before. I think I was expecting the clusters to be tighter, but in thinking about it now, at almost 300m and there was only about 20mm between 4 and 5, that's probably pretty tight.

I'll load up some with loads 4 and 5 and see how it goes.

The velocities all look about 100 ft/sec faster than I'd expect for the respective charge weights and barrel length. I'd be interested to hear what velocities your drop data confirms once you start shooting out further.

If there is no flexing "node" showing up that might be used to accommodate variations in ammunition - which is what a ladder test is trying to locate - then you'll just have to be that much more finicky with your reloading to control vertical stringing.

I think uniform monotonic POI rise like this is a good thing, and even better if that is the consistency you are getting at 285 metres!
It looks like you may be forced into shooting lots of rounds now to see if any variation in group size exists with variation in charge weight. But on the data presented so far any of those powder weights looks fine. Nice shooting by the way, and it already looks like a rifle with great potential.

Thanks @Puffin, the velocities surprised me a bit as well -it was with magneto speed sporter which I've never compared against an optical type, but velocities in my other rifles are usually close to published data.

I'll shoot a few more groups with those middle charges and see how it looks.

For what its worth I have just got a load for my Desert Tec 26" barrel 260 Remington worked out, 44 gr 2209 (as ever work your loads up follow the manufacturers guidelines this load may be well dodgy with your set up) Lapua 260 Rem cases and 123 gr Lapua Scenar's gives me 2985 fps (Magnetospeed V3)
Have used it on the range out to 700 yards and I am very happy with this set up punching paper.
I tried resizing ex military 7.62 cases and some old Lapua .243 cases it did not work out too well so I bit the bullet and got new .260 Rem Lapua cases never looked back.
7.62 gave early pressure signs and my old 243 Lapua cases had very inconsistent neck tension very noticeable when seating the projectile.
Probably should have neck turned the 7.62 but could not be arsed and I don't have a neck turning gismatron.
I was not happy with my 2208 loads in the .260 so 2209 it is for me.

Did you find any pressure signs during the test?

No pressure signs at all.

Ha ha then I'd go with 6 or thereabouts :D :P