I'm Thinking a having a 450/400 built. Rather than having it regulated with factory ammo, I would like to provide the builder with handloads for regulating the gun. That way I don't have to develop a load to match factory ammo. Will someone suggest loads with 400 grain bullets and powder readily obtainable?

To come close to Hornady's loading (2050) I would use 64 grains of Norma 203B + foam plug or tuft of polifill, 400 grain DGX atop a Federal 215M magnum match primer. I've been loading this since 2000 in my vintage British double.

Norma 203B/RL-15 in this configuration will give you extremely uniform velocities. Another advantage of Norma 203B/RL-15 with filler is reduced felt recoil.

73 grains of 4831 will give you about the same results, just more recoil.

This pretty much mimics Hornady's 3" factory loads in my work ups:
400 gr Hornady DGS/DGX
CCI 250 primers
77 gr IMR 4831

All are readily available and relatively cheap

3" or a 3.25"?

ISS

Three inch brass and ammo is much more readily available. I use Hornady 400 grainers and 4350 in my Krieghoff. 4831 kicks a lot more. I would not recommend Norma powder as it is too hard to get, at least where I am.

norma 203b and reloader 15 can be used interchangeably. Thanks very much.

Vol,
RL-15 is just another batch of Norma 203B. Norma sells it to Alliant and they repackage it as RL-15.

N203B is RL15; N204 is RL 19; and MRP is RL22. There may be more, but these are the only ones Alliant confirmed.

quote:

Originally posted by Vol717:
I'm Thinking a having a 450/400 built. Rather than having it regulated with factory ammo, I would like to provide the builder with handloads for regulating the gun. That way I don't have to develop a load to match factory ammo. Will someone suggest loads with 400 grain bullets and powder readily obtainable?

How long will the barrels be and what velocity are you looking for?

I like my 4831 load with a 400 gr bullet at 2125 to 2150 FPS and have had some doubles regulated for it. Its not a bad idea at all..I feel like most of the factory stuff is weak, and does not meet the standard although some such claims are made.

That said, Ive been able to regulate with loads other than regulation by trying different charges of 4831 powder to my required velocity with every English double I have owned and any Searcy double..mostly by using simulair bullets, Woodleighs seem to be the easiest to move to your required regulation..

If you think about it most doubles you buy, have no regulation load listed to go with that gun, it just a guess, so do the math and work up from there.

Duplicating Hornady ballistics would be ideal. The barrels will be 24".

l loaded some 400 grain Hornadys atop 64 grains of 203B and a 1/2" of backer rod. In my 8.5 pound Ruger No 1 the recoil was brisk but not unpleasant. The double rifle should weight about 9 pounds which should be about perfect.

Allan, a new 450-400 Merkel was just put up in the classifieds for $7,400. Beats the hell out of waiting for a build.

A 450-400 English double will normally weigh 10 to 10.5 lbs, Jefferys, Navy Arms, etc. A Searcy will go 9.50 to 9.75 depending on wood density..I like a 9.75 to 10 lb. double rifle for hunting DG.

You never have a regulation load with the old English guns, and most new ones as a matter of fact..but every double I have owned regulated with 80 to 83 grs of H4831 and most would do the same with IMR-4831 but at different grain levels..RL-15 with a filler has also worked for me with all doubles in that caliber, but again at different charge levels.

Single shots do not have to be regulated, so if you have a single shot all you have to do is sight it in..