I am going to load a freind that has been shooting factory H&H in his Ackley for years and decided if he has an Ackley imp.might as well make use of the added oomph. He didn't know it was an Ackley when he bought it but it has been a good shooter and he likes it so---! I cant find any loads for the Ackly and Barnes loads are all I could find for Weatherby. The Weatherby will chamber just a bit loose so I assume the Ackly has a little more powder capacity. He wants to use the Speer Grand Slams. Thanks--Rod in Wasilla

Ackley said the load data for the 375wby and 375AI should be interchangeable.He lists as max loads in the 375AI.
270gr bullet-4064 81gr 2830fps
235gr bullet-4064 86gr 3060fps
300gr bullet-4350 88gr 2740fps
300gr bullet-4064 78gr 2630fps
350gr bullet-4831 88gr 2650fps
The info in his book is from 1962 and the burn rates maybe different with todays powders. Its still a good place to start.Also,I believe the 4831 was the old h4831 but I could be wrong.

wasilla -- what weight bullet were you looking for info? I own a 375 AI built on a SAKO action and having a 26" barrel. Most but not quite all of my data is using the Sierra 300 gr. SPBT. Let me know if you are still interested in the better loads I found using the Sierra bullet with my rifle.

Rod--
Isn't Speer dumping the GS? I thought it was being phased out, and I'm kicking myself for missing getting them on closeout at Sportsmans Whorehouse. With my luck I'd finally work out the perfect load and run out of bullets....

Cheers,

Dan

quote:

Ackley said the load data for the 375wby and 375AI should be interchangeable.He lists as max loads in the 375AI

The 375AI and 375 Wby will have case capacties that are as close as one brand of brass to another. However you need to watch the Wby data. If it was designed for the normal Wby long throat using that data in a normal throated 375AI could give you some high pressure.

Speer is still making the 285 Grand Slams -- Midway has oodles of them. It looks like that is going to be the choice bullet for this endever. I still have not found loads I am comfortable stuffing in this guys gun. Weatherby loads aren't very common - yet!!?? To my knowledge his barrel is a AI without long freebore. I loaded some 30-378's for a Weatherby rifle-- HOLEY MACKERAL that Mother had some freebore! The Barnes 200 grainers could almost be left hanging out of the case. No way could I get close to Barnes seating recomendation -- could not EVEN get them in the magazine! If anybody has some loads out of a book, fire them this way. This guy is my foreman and if I crack his smokepole it ain't gona shine good on me!!
Rod in Wasilly