Soon to be a new reloader. I have seen on some threads, comments on loading a cartridge to an absolute minimum. One comment was that it would still push the bullet out of the barrel. What limitations is there to reducing loads to minimum? I was thinking of the 416 rigby as an example. It is quite obvious that a 41mag handgun round, if in a rifle, would not have a problem clearing the barrel....so wouldn't it be possible to reduce the load of a 416 rigby down to a 41 mag handgun round? What would be the limiting factor? The volume of the case? A specific powder to fill the case? Filler to fill the void? In theory then wouldn't it possible to reduce the 458Win mag down to the 45 auto levels? That is of course if you use the same grain bullets.... ? ?

I've played with light loads some -- best info sources are the Lyman and Speer manuals. Lyman has cast bullet loads that will do exactly that you are seeking.

The Accurate Powders manual also includes a lot of cast bullet data. Support the shooting industry, buy 'em all!

John

Modern Reloading by Richard Lee also has a great section on reduced loads that includes wich powders are best and wich are not safe and also a formula to tell you how much powder to use to get the velocity you want.

METOO,

I have played around for years with reduced loads.

The type of load you are talking about is real reduced and for these loads the shotgun powders such as Green or Red dot are excellent.

In a case like a 416 Rigby and with bullets around the 300 grain mark, you would probably end up using around 25 grains and be around the 1200 f/s mark. I am basing this on loadings for the 460 Wby with 400 grainers.

Accuracy with these loads can be extremely good although you will sometimes get the odd flyer. Fillers are not required.

The more difficult area with these big cases is the in between reduced load. In a 416 Rigby that would be perhaps a 300 or 350 at around 2000 f/s.

This needs quicker burning rifle powders such as 4198 etc.

The main problem area can be hangfires and the bigger the case the more likely it is to be a problem.

Calibers like the 458 and 460 add some difficulty because they both ahve a very large amount of freebore which makes ignition more difficult. I don't think the 416 Rigby will have big freebore.

One of the best reduced load powders for these in between loads was the old Reloader 7 as it igfnites very easily.

My favorite reduced load at the moment in the 375 is 39 grains of Hodgdon 4227 Extreme which is one of our Australian powders and a 220 Horhnady flat point. This load will group under an inch for 10 shots. It also groups just below full loads with 300 grain bullets. I think that powder would also work in the 416 Rigby. By the way, ignition is much easier with heavier bullets.

Unless you specifially want a 416 Rigby, I would recommend either 375 or 458 bore size for reduced loads as there are so many more bullets to choose from. The 375 is much easier to work with than the 458 and unlike the 458 you can get some velocities of around 2300 with say 220 grain bullets and still have very small recoil. You can't do this in the 458.

Another point worth considering with a lot of use of very reduced loads is the advantage of the belted case over rimless. Rimless cases get shorter and hence have increased headspace with each very reduced load that is fired. What happens is that the primer blows the case forward but the pressure of the load is to low to fireform it back again. Often the pressure in these loads is so low that a bulletr will still be a press fit back into a fired case.

Reduced loads are quite different to fire than the same ballistics generated from full power loads in a much smaller case.

I love to shoot them

Mike

Metoo,
The "theory" is simply to download your big-bore (you mentioned the .416) so it is inexpensive and completely fun to shoot.

I can make 575 grain cast, lubed and gas checked bullets for a little over the cost of linotype alloy. Or I can spend around $1.00 per bullet for Hawks or up to $2.00 per bullet for Woodleighs. It doesn't make sense when all you want to do is target practice from different positions.

To fill out the practice you have a few medium loads and a few full-on loads. Keeps you in the zone so to speak. Advice as to powders and resources is straight up. You can even call the pwoder companies and they'll give recommendations. I use 35 grains XMR-5744 in my .500.

Thanks for the info.... My gun club has a 40+bore competition group. I was thinking of the 416 rigby but realize that I wouldn't want to shoot 50 rounds from the bench of full loads very often ! ! Some of the responses give hope to accurate reduced loads. This looks like it might be a win win win situation. Reduced loads for competition, loading light bullets at high velocity for a second gun on a N.A. hunt, and also powering up with heavy bullets and load for possible future hunts in other lands... Thanks again, I'll ask for more help if I take the plunge.