Different weight bullets?

[norfolk shooter]

Right lets say a double is regulated to shoot a 480 grn bullet can you load develop a round to shoot a 500 grn or even a 450?? I've read that you can control the speed of the projectile to get the convergence right. If this is so I might consider a 450 NE 3 1/4!!

Many thanks as ever

 

[Bos Javanicus]

Possibly. What might regulate in one double might not regulate in another. It might be as easy as to get it to regulate, or not at all. Bit of a lottery really. Why not just stick to the 480's?

 

[norfolk shooter]

The only 480s I can get for reloading in the U.K. Are hornady dgs and dgx. I don't think the dgx hold together very well

 

[AZDAVE]

Yes you can work up loads for the 450 or any other double for that matter. My 450NE that I had a few years back was regulated with Hornaday 480gr softs and solids. I worked up a load for the 500gr Swift Aframes and 500gr CEB solids that had the some point of impact. The Aframes wound up regulating 75fps faster than factory and the CEB at about 50 fps faster. Could go into the stress and dynamics on working up loads. However Grame Wright in His great book Shoot the British Double Rifle does a much better job than I can. So I recommend when you get your double you also get a copy of this book and read it front to back several times then start working up loads. If you run into problems post a pic of your targets and the double guys here will give you some advice and assistance.

 

[zephyr]

You will learn in Wright's book that there is a 75% rule.... A bullet weighing 75% of the regulated round when loaded on top of the same charge will have the same POI.....
If you have a 480gr bullet on top of a charge of XX grains of your favorite powder, if you load a 350gr bullet on that same load you will get the same POI.

 

[norfolk shooter]

You will learn in Wright's book that there is a 75% rule.... A bullet weighing 75% of the regulated round when loaded on top of the same charge will have the same POI.....
If you have a 480gr bullet on top of a charge of XX grains of your favorite powder, if you load a 350gr bullet on that same load you will get the same POI.

Well that makes it nice and easy then. I just need to get the book in the UK. Christmas is only around the corner. Does that work if you go heavier??