The brown truck just dropped off some 140 grain ELDX. So would you say start with the same load as the Amax bullets using H-4350 for 260 Rem?

Yes, exactly!

Yup.

I believe my 260 shot a 140 A-max stellar at 43.5 gr H-4350

Thanks .

1 think the ELDX are 143 grain, the ELD's are 140

Finally got a chance to shoot some 140 ELD bullets. Made some up with 42.0 grains and some with 43.5 grains of H-4350 with overall length of 2.90. The loads with 42.0 grains shot a just over a half inch and the 43.5 grain loads shot just over an inch. I think I'll try some at 42.5 and 43 grains to see if I can get the most speed and accuracy . Any suggestions?

Try smaller increments. .5 grain increments is a fairly large jump in the 260 Rem case volume. 2.90" is a long COAL. Is this touching or jamming into the lands?

At 2.90 it's touching so maybe try seating a little deeper and see what happens?

Touching is ok, but you don't want it jamming. You should not be able to feel the bullet touching when closing the bolt. If so, it's too long. Will 2.90" fit in the mag?

Yes sir it fits. I can live with it shooting around 1/2" but how much velocity is lost ? Since it's a 20" barrel I want to get the best velocity I can .

Depending on how fast/slow burning your lot of H4350 is, 43 grains behind a 140 grain in a 260 should yield about 2800 fps in a 24"-26" barrel. You will gain/lose about 20 fps per inch with that combo, so about 80-100 fps less, so about 2700 to 2720 would get you in the ball park. But, with the bullet seated out to 2.90", it increases the internal case volume and may reduce your pressures some, and have a little less velocity. So, it depends, but the 2700-2720 should be real close. If you don't have a chrono, you can shoot it at distance (600+) and run the numbers to calculate your speeds.

My load for years was 43.1 grains of H4350 in Rem brass with a 140 VLD seated anywhere from 2.880" and chased the lands out to 2.950" (max mag length with an AI mag and the front plate removed). I put 2600 rounds down it, then set the barrel/chamber back 3" to get another 600+ rounds. I'll never set another barrel back again. Accuracy at best was a little under 1/2 moa after that, plus the loss of speed that never returned. I then went to 6.5x47 Lapua, and will stay with this round for a long time.

Thank you .

On my .260 my COAL is 2.862 so it feeds from AICS mags.. I'm only running 41.5 grains of H4350 at 2970 FPS.. I know that's fast for such a light charge, but if I jump to 42 grains, I start running into pressure issues. I would love to try the 143 ELDX bullets, but I'm having hell finding them .. My Hornady contact cant even get them for me from the factory...

That's extremely fast for that light of a charge...is this with a 120-123 grain bullet?

It's with the 140 Berger VLD Hunting bullet out of a Surgeon Scalpel and a 28 inch 8 twist Krieger #14 Heavy Palma..