Home Forums Hunting & Shooting Express Rifles and Big Bores Only Has anyone had accuracy or regulation issues because of ammo for double rifle?

I used the same load with IMR 4831 that I shot the above target with and it shot a little better.The ones marked R,and L are the IMR4831 load.I then shot some with a starting charge of IMR4350.Although I did not use a Chronograph the IMR 4350 recoil felt very light.
The rifle is regulated with IMR4831.
50yd target

I was at the range again and tried to use my Oehler 35P Chronograph to check speed but it did not work indoors.I then decided to shoot the double offhand and do so regularly to get me in top shooting shape.

I was looking for some Woodleigh 450NE, 480gr RN SN bullets but can't find some.Instead I found some 480gr bullets for the 458WM.
Will these work in my double? Could I crimp them in the same cannelure?

Here is a target I shot yesterday.

There are two four shot groups on this used target.The 500NE groups on the top left and the 400NE groups just to the bottom of the bullseye.I've shot much better groups especially with the 500NE but I am satisfied with the results in that both my doubles are shooting great.

I shot this group with my 450NE with 450gr NorthFork cup points at 50yds from a bench using IMR4831.
I fired three shots with the right barrel and one from the left.The right barrel seems to throw one off to the left from time to time and I am working on figuring out why.