Another factor that I have heard discussed in the "low density - slow powder" argument is the physical shape of the propellent grains, and the potential for detonation to take place. Examination of some damaged weapons have, as I understood, shown evidence of metal flow as a result of detonation.
One theory is that a compacted mass of propellent, loose in the case is able to impact the base of the round with sufficient force to intiate a detonation. The argument is that this is possible with the greater cross section of the slower powder.
...another argument is that the grain structure is broken up by the impact, dramatically increasing the available burning surface.. this is similar to the "do not tumble live rounds in a cement mixer" story..
As you say - until we find a way of reproducing the effect in a lab, we are all speculating.. however I am quite clear that dragons lurk in that particular corner of the tables..
09-02-2012 05:48 PM
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Lyman reloading manuals of which I have #45,#48 and #49 as well as the Lyman Cast Bullet Manual list quiet a few loads for the 54r as far as reduced cast bullet loads go. I prefer the fast to med fast burning pistol and SG powders
My M44 gets a pretty steady diet of the Lee 165 gr. tumble lube GC RN bullet using the Universal Load of Alliant 2400 and The Load of Alliant Red Dot in military style cartridge cases like .30-40 Krag, .303 British, 7.65 Argentine, .308 Win., 7.62x54R Russian, .30-06, 8x57 and .45-70.
I shoot both loads in my M44 with great success but I prefer the 2400 because I can use it with cast loads in my 7.62 x 54r,7.62 x 39,300 Sav. and my 30-30. MV runs anywhere between 1400 fps. on the low end with 170 gr. cast bullets up to 2K fps. depending on which cartridge I loading. I throw all the charges for these cartridges basically with my Lil Dandy powder measure and 3 rotors,you can't get any simpler than that.
Alliant 2400 according to Mr. Harris who wrote the NRA Cast Bullet Manuals and supplements stated that 2400 or Red Dot is neither case capacity or position sensitive when used with the prescribed load data,meters great,burns cleaner in the longer rifle barrels and has a good bit of latitude especially the 2400 to allow you to work up an accurate load.
Cast bullets in military rifles.
Cast Bullet Loads for Military Rifles - Article - Cast Boolits
My first 5 shot cast bullet group at 50 yds.
Last edited by SKS50; 09-05-2012 at 03:56 PM.
Really Senior Member
I;m not sure where you get the idea that reduced loads are "only" used with faster powders when this is absolutely not correct. Many loading manuals have reduced loads of medium and slow powders to make reduced recoil, etc. loads.
Originally Posted by jarmann
As for detonation, this (elusive) phenomenon is most closely associated with GALLERY loads (small charges of fast burning pistol powders) in which the internal case (may) result in a flash-over detonation etc. As was alluded to above, NOBODY has been able to reproduce this. What is a ALSO wrong with Gallery loads, especially with fillers/wadding is BARREL "RINGING." Not that I don't occasionally use poly-wadding loads in straight walled rifle cases (45-70/38-55), but I know what the risks are.
4895 and Varget are both DANDY options for reduced loads but make sure you don't stray below manual limits. Likewise, I am a BIG fan of BOTH Trail Boss and Red Dot for rifle loads with JACKETED or LEAD bullets in bottleneck and straight-walled cases..