Gentlemen: I've been shooting my ( Ruger)Rigby 416 since they first came out. As a matter of fact, mine is one of the first 50 made with the swivel on the forearm. Using the Hornady manual, I worked up loads using 90.2grains of IMR 4350 and Hornady RNs and the old style solids which I still have a good supply.

Since my favorite bullet is the Swift A Frame, I decided to try some loads using the formula described above. This was before Swift came out with their loading manual. The loads worked great, shooting UNDER half inch groups with 400gr A Frames and the solids print right next to them. Absolutely zero pressure indications,i.e., no sticky bolts, flattened or enlarged primer holes, nothing, even in the hot 95 plus degree Florida summer. Hell, I've been using the same cases up to 7-8 times with hardly any trimming involved. MV runs about 2390-2405 fps.

According to the Swift book, the maximum load for the 400gr A Frame is 89 grains. By their own admission, Swift concedes that their loads are very conservative. Since I do not have access to pressure measuring equipment, do you folks think I am flirting with disaster? Thanks, jorge

Hola Jorge

Pues no , because you have a super strong action like the Ruger , the rifle could be built into a 416 Weatherby Magnum with out problems , then a bit of over pressure in a very low pressure cartridges like the Rigby is not a problem , a different matter it's you over load a high pressure cartridegs like the new magnums , loaded to the limit , if you have no extraction problem or sticky bolt or loose primers in you hot Orange Park / Florida weather , and get one inch groups , just be happy

Saludos

Daniel

90.2 v 89.0 grains of powder, all in a case that holds about 100grains. No, I don't think you are in a dangerous spot. I'll bet you'll find larger lot to lot variations in your powder of choice.

Looks like you've done your homework, keep up the good work!