But of experienced help if possible please.

Rusty Gate

Well-Known Member
I sent info for a light 100gr 6.5X55SE round using RS50 to Reload Swiss & they came back with this info from their Quickload.
I thought the modern actions were OK to 55000psi & the proof test was 60/65 or similar.
The Nominal load here is 39395psi but velocity is low when considering the Sierra manual of 3200-3400fps for Accuracy/Hunting. Are the Quickload pressures normally that much lower or is that the OLD Swiss safety margins?
 

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srvet

Well-Known Member
I suspect that this may be in deference to the older weaker 6.5x55 rifles out there. The chart appears to show the predictions up to 46.2gr all being below max pressure assuming the Quickload simulation is correct. Obviously it is up to you what you do from here, but I would consider working up gradually towards 46gr whilst watching for pressure signs carefully. It would also be useful to chrono the rounds whilst you are doing so to check on velocity.
 

Davee

Well-Known Member
From limited experience with RS powders always chrono the test loads. There appears to be a problem with Quickload and RS powders, I have found -with 60 and 62- that at lower charges QL over estimates the fps, and this changes to under estimating at higher loads. With MY setup I have found that this change over happens at about 2770 fps -measured- above that the error increases with the load, by 2900 fps -measured- it is more than 100 fps faster than predicted. At 2500 fps it is 80 fps slower than predicted. I have not chased the velocity higher as I found a consistent sweet spot at 2780. Others have noted similar results, some have suggested altering the QL burn rate to make the predicted equal to the actual, however I have found that this merely changes the changeover point. I find that with Viht powders the predicted and measured velocities are very close, and, as others have found similar discrepancies with RS, I assume -dangerous- that it is not me or my rig. One of the things I have noted is that there appears to be more variability in extrusion length with RS than with Viht powders.
The QL max pressure -55114 psi- is for Skan or SE rifles, if my memory serves me correctly the old military Mauser max pressure was close to 47,800 psi. Open to correction.
I would -as suggested by Srvet- start at 42gn and work up to 46 with due regard to pressure signs. -46 grain prediction is 3011 fps- Chrono if possible. But, -as Lateral suggests- there are more suitable powders available.
 

big ears

Well-Known Member
RS web site quotes RS52, 60,62&70 as best powders with 60&62 top choice. RS50 is equivalent to N140 which I found didn’t work in the swede. Needs slower powder to get the best.
 

25 Sharps

Well-Known Member
RS web site quotes RS52, 60,62&70 as best powders with 60&62 top choice. RS50 is equivalent to N140 which I found didn’t work in the swede. Needs slower powder to get the best.
I have a very good load for 100 gr amax over n140, it’s a crap case fill but reasonable velocity and good accuracy. From memory load was 39 gr and speed was just over 3000 FPS maybe up to 3050, top speed for Viht’s load data is 3120with N530 which is double based

100 is light in the swede so calls for a faster powder.

Sierra’s data for 3190 is with H380 and IMR 464 so all on a similar burn rate to N140 RS50/52.

The interesting thing is Sierra’s max for H380 is 47.2 gr and 3190 FPS but Hodgdon have a max of 48 gr and are only giving 3092 FPS. Same bullet. Hodgdon do list loads around 3180 but with H414, win760 and varget
 
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25 Sharps

Well-Known Member
I sent info for a light 100gr 6.5X55SE round using RS50 to Reload Swiss & they came back with this info from their Quickload.
I thought the modern actions were OK to 55000psi & the proof test was 60/65 or similar.
The Nominal load here is 39395psi but velocity is low when considering the Sierra manual of 3200-3400fps for Accuracy/Hunting. Are the Quickload pressures normally that much lower or is that the OLD Swiss safety margins?
The QL data readout is for 55k they have just not taken it that far. Out of interest why 100 gr, fox load?
 

25 Sharps

Well-Known Member
I have just checked Sierra’s data is with a 29.5” barrel, hodgdon for a 24” and the RS data in the OP is for a 22” barrel, that accounts for the extra velocity.......
 

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