GeezerD
Bearcat
gramps said:It bothers me that you are over max with your powder charge, and aren't using a chronograph. You may find the only indication you get of overpressue will be BOOM!GeezerD said:Today I did some shooting with my 77/357 using Lil-Gun powder. The temperature is 90+ degrees with high humidity so high pressure loads are more likely to show indicators of excessive pressure.
Load 1 - 158gr XTP, Sig brass, Win SPM primer, 20gr Lil-Gun, 1.650 COL - No Excess Pressure Signs
Load 2 - 180gr XTP, Sig brass, Win SPM primer, 18gr Lil-Gun, 1.720 COL - No Excess Pressure Signs
Load 3 - 200gr RN Sierra Pro Hunter .358 dia., Win SPM primer, 17gr Lil-Gun, 1.870 COL - No Excess Pressure Signs
These loads were fired in my 77/357 which has a cylindrical throat that is .358 dia. and is .450 in length. All loads are well in excess of Hodgdon data. Load 3 is 2gr more than the maximum load suggested for 180gr XTP but uses a 200gr bullet that is .358 in diameter.
Now I need to chronograph these loads and do some accuracy testing. ----------- GeezerD
http://www.rugerforum.com/phpBB3/viewtopic.php?f=11&t=239550
Good luck.
gramps
Gramps - I did cronograph load #1 at - 1972 fps avg with an extreme spread of 87 fps. I did a substantial amount of research on this before I started this project. The freebore in the chamber allows loading to an overall length that is longer than the 357 Maximum which in a T/C can be loaded with 21.6gr of LilGun behind a 180gr XTP.
None of the loads have a compressed powder charge or use a heavy crimp and freebore has the effect of lowering the pressure for a given load. I have also checked all of the cases for head expansion and loose primers - nothing.
A fellow over on the Marlin Owners forum has been using 19gr behind several different 158gr bullets with good results in his 1894 levergun which requires a shorter COL and has a much shorter throat.
It is good to hear that Ruger is returning the 77/357 to production status so if I blow this one up, I can get another one. ------------------- GeezerD