I have ben away from home the past week & while I did get a little computer time it was limited, so just had about 6 pages of this thread to catch up.
Interestingly enough, at least based on the Alliant catalog I have, it would appear that Alliant Powder pretty much agrees with Thomas. They list their powders by burn rate, from fastest to slowest. Bullseye and Red Dot are #1 and 2, respectively. #3 is American Select, #4 is Green Dot. Alliant refers to the "less felt recoil" with American Select, and "lower felt recoil" with Green Dot. Since the only really commonly-used shotgun powder that's faster is Red Dot, and since several Alliant products are slower (Unique, Herco, Blue Dot), and since they don't tout ANY of those slower powders for recoil reduction, they seem to be telling us that relatively fast-burning powders are the ones to go to, if you're looking for less recoil.
Larry you best go back & study that Alliant manual "MUCH, MUCH More Carefully". You will find they were in fact not comparing American Select with such powders as Unique, Herco, Blue Dot etc at all but in fact with to quote them "A Typical ""FAST" Powder". They used 2 entire pages in this old guide I have (copyright 1996) showing "Typical" pressure curves of two powders & stating the lessened "Felt" recoil from American Select was due to its ""Slower"" burn than a typical Fast Burn powder. This was not even dealing with hunting, magnum etc loads which push heavier shot charges to higher velocities & produce heavier recoil for rather obvious reasons. NO INDEED, it was dealing strictly with target loads, & I ask What poweder is more typical of a fast burn powder for target loads than ""RED DOT"". The whole discussion centered around the fact it burned ""Slower"". In fact the only other powder mentioned on those two pages is Red Dot, & though they did not "Directly State" this was the comparsion powder it was rather obvious. This guide also give a "Relative Quickness" figure based on Bullseye as 100%. ReDot is 94.1%, American Select 81% & Green dot 77.9% with Unique @ 61.6% so American Select & Green Dot are so close together one wonders why they chose to make both.
If you cannot understand that is diametrically opposed to Thomas' theory then you best go back to "Understanding Reading 101".
I will see if I can figure out how to post a scan for all to see, I don't want anyone taking this just on my word, but let the facts speak for themselves. If not I will be hollering for someone to post it for me from an E-Mail once I get it scanned in.
Further for all there is a very good discussion on recoil contained in Hatcher's Notebook. He there assigns a value to the velocity of the escaping gasses as 4700 fps. Since this is an extremely hard item to measure he further states that for most shotgun, pistols & ordinary rifles a very good approximation of the total recoil element can be obtained by multiplying the powder wt times 1.5. Thus if you were calculating the recoil for say 1oz (437.5grs) shot 30 grs of wadding with a 20 grain powder charge you would use 30 for the powder rather than 20.
Note also that when we speak of slow & fast powders tihis is a relative term, in the total powder spectrum ""ALL"" shotgun powders are Fast.
The reasoning Alliant used is theoreticly true & corresponds exactly with that laid out by FNB25 several posts back. With all due respect to both, I am at this point in time throughly convinced that within the realm of powders suitable for a given load the various factors more or less cancel one another & that differences are of too mimnute a nature to be determined by human feel, unless there is some vast differences in the basic make up of the load.
Based upon IMI's statements, which I have no reason to dispute, I can only surmise they were in fact & indeed testing one of the dense powders against one of the older bulk powders which greatly different wt of the powder charge would account for an ""ACTUAL"" increase in the recoil. If I am not badly mistaken bulk powders had a far longer common usage in the UK than in the US. DuPont bulk shotgun powder was available even here until around the 1960's though by then was not too often used, & was predominately sold to re-loaders.
The fact that Thomas gave us ""NO"" particulars of the test as to what in fact was used, makes it worthless for determing much of anything & his reasoning is simply Ludicrous, certainly not worthy of anyone Claiming to be an Engineer. I am not an engineer but in 35 years of machine shop experience with most of it related to the aero-space industry I certainl hob-nobbed with a lot of good ones & can simpl;y not imagine a single one of them coming up with the conclusion that the recoil was simply "Too Quick" to feel from the fast powder.
