Should'a did this pressure trace a long time ago but I feel more confident with my results using Buffalo Bore as my control. I have tested several semi-balloonhead 44WCF unheadtsamped cases as well as a few Western cases with Goex FFFG and get consistent 12,000psi. With Swiss FFG, a more dense powder, I got 14,000psi.
When Winchester first offered smokeless powder in the 44 WCF back in 1895, they used Dupont #2, then Sharpshooter and finally SR80.
"Twenty two years after its introduction, the first .44 W.C.F. smokeless powder cartridge is found in Winchester's catalog No. 55, dated August, 1895. In its manufacture, Winchester used 17 grains of DuPont No. 2 which was a "bulk" type smokeless powder patented on August 22, 1893. DuPont's description of "bulk" smokeless powder indicated that it was to be loaded in "bulk" measure just like black powder.
In the .44 W.C.F., 17 grs. of DuPont No. 2 Bulk Smokeless occupied the same volume as 40 grs. of FFG. Velocity was cataloged at 1,300 f.p.s. for a 55 f.p.s. increase over the the black powder cartridge. To identify the new .44 W.C.F. smokeless powder cartridges from those containing black powder, which looked identical, Winchester put a "W" in a circle on the primer." Dupont #2 had a similar burn rate as today's IMR-4227. However, Unlike 17gr of Dupont #2, 17gr of IMR-4227 is not a case capacity load but is a published load.
Lyman's 49th handloading manual shows a max load of 18.5gr of IMR-4227 with a Speer JHP@ 1,212fps. This load only gave me 1,097fps. 20gr of IMR-4227 produced 1,297fps but also created 12,000psi, just a tad over the 11,000psi max. A caseload (26gr) of IMR-4227 with the popular Magma type 200gr lead bullet resulted in 1,733fps but produced 20,913psi....only safe for Group II rifles like the Winchester 92/94 and Marlin's 1894. I am getting consistent 10 shot 4" groups at 100 yards.
Lyman's 49th lists a max load, 17gr of IMR-4227 with a Lyman 427098. They claim 1,083fps with no pressure listed for Group I rifles like the Winchester 73'. I tested 17gr in my 20" MGM barrel I used for high pressure testing. 17gr with a 427098 resulted in 1,127fps (replicating modern Winchester Super-X ammo velocity) @ 9,500psi. I tested 20gr with a 43-215C (427098 replica) resulted in 1,418fps @ 16,500psi but also included .5cc of PSB shot buffer to keep the powder at the back of the case. IMR-4227 is position sensitive and could be why some of my early velocity tests were lower than the manual.
22gr with a Winchester 200gr JSP (.425) produced 1,386fps at a lower 12,000psi, which closely replicated early Dupont #2 velocities. I feel safe using 12,000psi loads in my Winchester 73 replica and revolvers with .425-.427 lead or jacketed bullets.
I don't know which came first here, Shareshooter or SR80, but....
L&R Sharpshooter (burning rate similar to 2400 as well but easier to ignite since it is perforated) It was specifically used in black powder frame firearms. Since Winchester's first ammo boxes instructed not to be used in pistols, I assume Winchester may have used SR80 type powders rather than Shareshooter....but it still gets confusing.
Sharpshooter and SR80 had a similar burn rate as today's 2400. Although 2400 is an excellent powder, it too is not a bulk powder like Dupont but yet is bulky enough to prevent an accidental double charge without the powder overflowing the case. 20gr of 2400 can produce some hefty pressures.
20gr of 2400 with a 200gr Speer JHP produced 1,672fps @ 15,618psi, while a Seirra 210gr DCHP produced 1,640fps @ 19,500psi.
Sharpshooter was developed by Laflin & Rand, then offered by DuPont after they purchased L&R. Hercules produced it from 1912 on. It was a very flexible powder and after about 1900, was THE powder that was used in most all the b.p. cartridge factory smokeless loadings including the H.V., H.P. and W.H.V. (High Velocity) cartridges. It was used right up to the 1950's, after which it was discontinued.
Load data on the back of a Dupont Sharpshooter can notes 44-40 High Velocity, 19gr.
https://curtisshawk21.wixsite.com/44centerfire/early-smokeless-powders
