Thread: What's the Deal?

I was shooting 42gr of 2209 with 140Amax out of a 20" 6.5x47 too. I found pressure too high and have backed off to 40.9gr (for better accuracy as well, bonus). Previous velocity was 2810fps average via my Shooting Chrony f1 (oh no!) and that velocity was accurate for centre hits to 910meters (As far as I ever bothered to shoot it) so my crappy chrony can't be too far off. I haven't had a chance to chrony the new load but I'm making an educated guess of between 2740-2760fps.

My .260 research for whenever I get around to loading it has indicated that a max load can be anywhere from 41-44gr of 2209 (H4350, it's the same thing) and a 139/140gr will get anywhere from 2700-2850fps in a 22-24 inch barrel, depending on the brass and the chamber and the barrel so 2644fps for 42gr of 2209 sounds reasonable to me. Loads seem to be quite inconsistent but H4350/2209 seems to be universally 'the powder' for a 140 in .260.


Similar to 65x47 actually - some people can't get over 40gr of 2209 with a 140gr without hitting pressure, I was at 42gr and only getting real pressure on 30°+ days when I left my ammo lying in the sun - sticky bolt, ejector mark and 1-2% pierced primers. Normal weather, no signs at all.

R93 it's a customish rifle. Howa action trued with MAB 1:8 22" PTG reamer for SAAMI chamber spec .298NK .088 FB I think Abe set headspace at 1 thou or 2. Will measure fired case length and get back to you.

When Abe built my barreled action he said my MAB barrel was very tight. He even had to make a new pilot for the reamer, so that might be why I'm slow also?

Originally Posted by Normie

When Abe built my barreled action he said my MAB barrel was very tight. He even had to make a new pilot for the reamer, so that might be why I'm slow also?

No not really. Should be faster if anything with less powder.
Hence my question of measuring length of the 2 cases.

Sent from my iPhone using Tapatalk. So please forgive my sausage fingers!!!

Originally Posted by R93

No not really. Should be faster if anything with less powder.
Hence my question of measuring length of the 2 cases.

Sent from my iPhone using Tapatalk. So please forgive my sausage fingers!!!

May explain early pressure signs tho.

Originally Posted by gimp

Shooting Chrony f1 (oh no!)

Shooting Chrony is not bad, it's just that they are light dependant and reading will vary with the light.

Originally Posted by Norway

Shooting Chrony is not bad, it's just that they are light dependant and reading will vary with the light.

I know no problems with mine when used in clear direct sunlight, readings appear 'accurate' and have done so for the 5 years I've had it. Even put it next to jake wires (he didn't trust his) and they read the same.

The super chrono looks nice for more portability though.