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DblTap · November 5, 1999, 04:02 PM

Winchester has stopped making 540, which is what drove me to find another powder. VitaVouri (sp?) is imported and is sometimes not widely available.

I'm using IMR 4756 in a compressed load. I have a new SV open gun with a 7 port comp (three on top and two on each side) and it takes 9.2 grains to make a 178-180 PF. The powder is on the slow burning side so the felt recoil is pretty soft (softer than Win 540). The powder charge fills the case to about 1/16 of an inch from the top, so reloading goes a bit slower (have to slow down the handle when the rounds are moving between stations or you spill some). I have also cut about half of one coil off the spring under the shellplate locator ball on my Dillon 650. This stops the shellplate from "snapping" into position and spilling out the powder.

I find that the load, even though it is compressed, still produces enough gas to make the comp work very nicely! It is fairly clean, on the comp end anyway.

I tried 7625 but found that the increase of just one tenth of a grain caused pressure signs (primer flow and brass bulging) in my gun. The dot tracked off the C-More lens with the 7625, but stayed on the standard IPSC target and in the lens with the 4756.

As with all loading information, start lower and work your way up. YMMV.

DblTap

November 5, 1999, 04:02 PM	#2
DblTap Member Join Date: January 22, 1999 Location: Farmington Hills, MI Posts: 72	Winchester has stopped making 540, which is what drove me to find another powder. VitaVouri (sp?) is imported and is sometimes not widely available. I'm using IMR 4756 in a compressed load. I have a new SV open gun with a 7 port comp (three on top and two on each side) and it takes 9.2 grains to make a 178-180 PF. The powder is on the slow burning side so the felt recoil is pretty soft (softer than Win 540). The powder charge fills the case to about 1/16 of an inch from the top, so reloading goes a bit slower (have to slow down the handle when the rounds are moving between stations or you spill some). I have also cut about half of one coil off the spring under the shellplate locator ball on my Dillon 650. This stops the shellplate from "snapping" into position and spilling out the powder. I find that the load, even though it is compressed, still produces enough gas to make the comp work very nicely! It is fairly clean, on the comp end anyway. I tried 7625 but found that the increase of just one tenth of a grain caused pressure signs (primer flow and brass bulging) in my gun. The dot tracked off the C-More lens with the 7625, but stayed on the standard IPSC target and in the lens with the 4756. As with all loading information, start lower and work your way up. YMMV. DblTap