I have taken the liberty of posting a thread from another forum to cast bullets to get more eyeballs and seek more information.
http://forums.accuratereloadin...721060011#9721060011

Any more light on this subject would be appreciated.

Also posted on the other thread.

Apparently a case (pun intended) of SEE although this is the first time I've actually seen it with a cast bullet. Lighter loads of 5744 do not burn efficiently in such large cases, especially when loaded and raised from the muzzle down position as most doubles are. I also might add that I had a disaterous experience with 5744 in a trapdoor. I also am pretty meticulous but forgot to do the "visual" inspection of the cases in the loading block before seating the bullet. The 5744 had "bridged" in my powder thrower and I had one very light cahrge and one excessive charge.

I'm not saying that IS what happened in this case but it seems more likely than an SEE with a cast bullet. I have seen some pretty badly leaded barrels (couldn't even see much rifling) and still not give excessive pressures to blow up a rifle. Many times we are not want to look at the real problem and instead seek a technical or mechanical blame. Most often the reason is "pilot error".

Back to the question of this thread though. many years ago I helped a very nice old gentleman wotk up a cast load for a very nice .450 Nitro-express (3 1/4) double rifle. We used a Lee C548-500-FN sized at .459 and lubed with Javelina NRA 50/50 lube. Hornady GCs were used. The alloy was a 50-50 WW/linotype with the bullets being water quenched from the mould.

We worked up to 70 gr of 3031 with a 2-3 gr dacron filler (not wad) over the powder. The muzzle velocity (Oehler M10) was 2130 fps which duplicated the Kynock factory loads for which the rifle was regulated. That cast bullet also shot to "regulation" and was every bit as accurate as the Kynock load. He had 40 reloadable cases and after working up the load we loaded all the cases and shot them in one very pleasant session. Not a bit of leading and wonderful accuracy. We were just neck sizing the cases in my 45-70 dies and they worked fine. I probably cast and loaded a couple hundred rounds after that for him and went shooting several times with him. Alas he passed away a couple years lator and I then could not afford the rifle.

My recommendation is to use a good gas checked cast bullet of equal weight to factory loads, a good 50/50 alox/beeswax lube, a medium burning powder and a dacron filler in either of the mentioned cartridges.

Larry Gibson

5744 has been a very good cast powder,but i have heard of it causing these type of incidents occasionally.
i don't use it.
i don't see a double rifle as any different than any other rifle it has a pressure limit[keep your loads under it]
if your cast boolits are large enough,and of the proper alloy you should be able to use a load with enough oomph to actually get some practice from the rifle not just a pooph.

IMO accuracy would suffer with a heavily leaded throat. Why did they keep shooting or if it was lead compacted enough to elevate pressures the metalurgist must be sure that it happened with one shot rather than with raising pressures the cases would show evidence of.

Lamar, it is true that rifles are rifles but cases are not cases. I think the correct answer for me is to avoid reduced loads in the huge Nitro cases regardless of powder choice. They were designed for Cordite sticks 2-1/2 inches in length or longer and no modern powder has the physical characteristics needed for a reduced load without using far too much filler.

Even comparative full-house loads of Rel-15 or IMR 3031 require some amount of filler due to the huge case volume. The big cases simply do not follow all the same rules that modern bottle neck cases follow. Or rather, they have some extra rules all their own.

There was no evidence of creeping pressure in any of the fired cases. Ten shots total from two barrels were fired before the incident with no discernable problems at all.