Not enough powder?

[Trailrider]

I am tryin ta digest alla this, so correct me iffen I'm wrong. What yer sayin is iffen I'm settin the paper targets on fire at 20 yards I prolly need ta tighten up my crimp a little?  WM

That may help, all other things being equal (i.e., the powder charge not being totally too light for stable burning)! I always recommend as firm a roll crimp on CAS cartridges as you can put on the mouth of the case without bulging the case away from the side of the bullet. I know, the old .38 Special 148 gr Full Wadcutter target shooters believed crimping was detrimental to accuracy. I have NOT found that to be the situation. And I have seen a Colt Python with a .38 Spl case still in the remains of the chamber.  I doubt seriously that a double charge of even Bullseye was responsible as Lane Pierce (IIRC) ran pressure tests with double and triple charges of Bullseye behind 158 gr bullets, and the pressures generated by the double charges were LESS than a standard factory load of .357 Magnum.  While a double charge might blow an M&P revolver, it should not blow a Python! (Yes, the triple charge would have.) I suspect that an ignition delay was responsible, but with out further data, I can't say for sure.

[Tascosa Joe]

back to the OP queries, I really must dig out my old Lyman manual and compare it to the newer loading data, but I cannot imagine that the powder formulation of Unique has changed in ( dare I say it) 40 years.

Professor:  I have Lyman manuals going back to 1953 as well as the #49 which I think is the most current.  There are significant differences in the max load of Unique in the old cowboy calibers. (.45, 44WCF, and 38WCF) between the old and the new.  I dont know when they changed because I used my #45 Book from the time I started reloading in 1972 until  a couple years ago when I wanted to see loads with more modern powders.   The guru's that write for Handloader preach we should not use that old data.

T-Joe

To all the other folks who participated in this thread, THANKS I really enjoyed it.

[joec]

Professor:  I have Lyman manuals going back to 1953 as well as the #49 which I think is the most current.  There are significant differences in the max load of Unique in the old cowboy calibers. (.45, 44WCF, and 38WCF) between the old and the new.  I dont know when they changed because I used my #45 Book from the time I started reloading in 1972 until  a couple years ago when I wanted to see loads with more modern powders.   The guru's that write for Handloader preach we should not use that old data.

T-Joe

To all the other folks who participated in this thread, THANKS I really enjoyed it.

Actually Unique has changed a couple of years ago, and got that information from direct from Alliant powders. It seems the tried to make it cleaner and it also affected the charge somewhat. I always cross check old data with new and use the new especially with powders I just bought and haven't been stored any length of time.

[wildman1]

No, I think it means you're way too light on powder. If you ain't incinerating the targets, stiffen the load!! 

Ya may be right JD. 35 gs of 2f in a 45 Colt may not be enough powdah. WM

[J.D. Yellowhammer]

I use a scientific method to judge my black powder load when I shoot a match: how many steps away does the timekeeper go when I shoot?  Anything over 2 steps means the load's adequate.    Sounds like your load would qualify.

[Delmonico]

Professor:  I have Lyman manuals going back to 1953 as well as the #49 which I think is the most current.  There are significant differences in the max load of Unique in the old cowboy calibers. (.45, 44WCF, and 38WCF) between the old and the new.  I dont know when they changed because I used my #45 Book from the time I started reloading in 1972 until  a couple years ago when I wanted to see loads with more modern powders.   The guru's that write for Handloader preach we should not use that old data.

T-Joe

To all the other folks who participated in this thread, THANKS I really enjoyed it.

You must not have got the memo about 20 or so years ago, the companies have went from the old crusher method of reading pressures to the newer strain gauge methods that use those new fangled computer things.  What we now have is a much truer method of seeing how pressures build, how it spikes and all that good stuff like that.    I was sure they sent a memo around quite a few years ago, or perhaps I found that out by reading the latest info they offer.

[Trailrider]

Just to clarify about the term "detonation": A detonation produces a pressure wavefront velocity of 25,000 ft/sec or more. In point of fact THERE IS NOT SUFFICIENT ENERGY IN SMALL ARMS SMOKELESS POWDER TO PRODUCE A TRUE DETONATION!  HOWEVER...that does NOT preclude a catastrophic OVERPRESSURE, of which there are a number of documented cases (including the one in my book).

As to the changes in the WCF cartridge powder loadings from older loading data to the present, it DOES HAPPEN, AND SHOULD BE PAID ATTENTION! A number of years ago ballistics engineers with whom I talked personally to me they considered a 10 percent variation in burning rate FROM LOT-TO-LOT to be acceptable! Changing the formula of Unique, etc., undoubtedly can change the burning rate sufficiently to warrant re-testing, and re-publishing of loading data.

There is no question that the newer methods of measuring pressure, i.e., peizo-electric sensors, strain gages, etc., gives us more accurate information on the safety margins of our guns and pressures. There can be a significant difference between the pressure levels read by copper or lead crusher and those read by piezo-electric equipment. For that matter, there are different techniques for measuring with electronic equipment.  European methods differ from North American methods. And it is difficult to correlate copper crusher data with electronic instrumentation. The Oehler M43PBL uses strain gages installed by the user on the barrel of the gun over the chamber.  This will give you a reading on the strain on the barrel (or chamber of a pistol), but it is only a relative reading. It will show you a pressure/time curve of the pressure being generated, but you need a "standard test round" to calibrate for absolute readings. In addition, this method depends on the cartridge case pressing on the chamber wall before the steel of the chamber will expand and cause the strain gage to stretch enough to give you a reading. It takes about 7,000 psi to expand the case against the chamber wall.  So, the Oehler equipment WON'T register ignition transients that occur at very low pressures. It IS great for comparing higher pressure characteristics, including smokeless versus black powder! And, YES!, you can find slight smokeless loads with pressure/time curves that come close to BP p/t curves. Of course, all this pre-supposes you don't mind messing up the bluing where you cement the strain gage to the barrel or cylinder!   Don't ask about cementing strain gages to stainless steel. It can be done, but wear a football helmet so you won't injure yourself banging your head against the wall!      

Bottom line is READ AND HEED the data in the published manuals. You get a more harmonious outcome!

[Delmonico]

And stick with the latest up to date data.