I still think that lack of a gas check is your major problem.My bullets aren't gas check. I had brought 3 Enfields that day 2x P14 one sporterized on Full wood and on Enfield Mark 4 No 1 the P14 are normally tack drivers. I really think it could be light bullets and yes I kind of eye balled the load from 308 info. I am going to load some jacketed ammo to specs and see if that makes a difference.
If I get the lead bullets going 2000ft/s wouldn't that lead up my barrel pretty bad?
Thanks for all the great info
2,000 fps is certainly doable with gas check bullets, but I think completely out of reach with flat base bullets and 165 grains should not be considered as light bullets in a 303 British.
Regarding leading, I think the major cause of leading in a barrel is the condition of the barrel. I have owned and shot, quite extensively, five different revolvers in 44 magnum, two S&W and three Ruger Super Blackhawks. They all varied in how much they leaded. One Ruger and one S&W collected no, or very little lead. One Ruger leaded up so badly that I soon got rid of it.
Most of the advice at that time was If the barrel leaded up, polish it. Various types of very fine abrasive, including Bon Ami, were suggested.
Fifty years ago I did a lot of experimenting with cast bullets in a 30-06 rifle. Of course, at that time I didn't have access to a chronograph, but I had the same Lyman Handbook of Cast bullets, the first edition, which is in front of me now as I type this.
I used two or three different types of cast bullets, all with gas checks, many different types of powder and every type of lubricant I could conceive. I was trying for the most speed I could get coupled with reasonable accuracy and for this purpose I did best with slow powders, with the old war surplus H4831 giving me as good of groups as any, with about three quarters of so, of a case full. As far as I could see, one kind of bullet lube could not be distinguished from any other type. Thus, I started and finished with the ancient standby, a mixture of bees wax and beef tallow. In hot weather more wax than suet and the opposite in cold weather.
Your top loading with cast is always determined by velocity, not too much pressure for the rifle. When you get to a certain velocity, accuracy goes all to hell.
I was using a Husqvarna rifle which had a very smooth barrel and I had absolutely no problem with lead in the barrel. It simply was non existent, even with the cast bullets loaded so fast that they had blowby, from too much pressure.


















































