Data request US869 264mag

[6.5x55mm]

Pls remove

Does anyone have any data for the .264 mag using this powder.

 

[Andy]

I am going through a similar experience with a wildcat (6.5mm ARP) that is a 300 Win Mag necked down - essentially a 264 Win Mag + 8%. Obviously no data exists for that round, so I'm using 264 Win Mag data as a starting point and going up rfom there, but adding no more than 4% more powder.

How this applies to you is that since no data exists for US869, the best approach is to use H1000 data (a slower powder) and work up until the muzzle velocity matches it or slightly exceeds what you get for H1000 (which Hodgdon publishes), or the case is full - whatever comes first. If you don't have a chronograph, all I'm prepared to suggest is that you use available data for a slower powder, like H1000, Reloder 25 and the likes.

 

[dan belisle]

Isn't H870 very close to US 869 in burning rate? I seem to recall reading that somewhere. - dan

 

[Andy]

Isn't H870 very close to US 869 in burning rate? I seem to recall reading that somewhere. - dan

Yes, it's a wee bit faster than US869.

Seems strange putting "H870" and "faster than" in the same sentence.

 

[dan belisle]

LOL, true. Faster then charcoal seems a better fit. - dan

 

[6.5x55mm]

Thanks guys. Thats the whole problem trying to match H870 but do not have any left.

 

[dan belisle]

Well, subtract 5% from 870 data and start there then. - dan

 

[Pathfinder]

Does anyone have any data for the .264 mag using this powder.

did you ever manage to work up a load with that powder ?

 

[6.5x55mm]

Data so far

Please keep in mind my rifle is throated to be able to maintain factory O.A.L. no matter what bullet I choose. HUGE difference in performance.


Bullet 140 berger Winchester brass Rem 9 1/2 primer 77gr of US869 with a muzzle velocity of 3157 average.

My best load to date is 74.5 gr of H870 with a muzzle velocity of 3182 average.