Soft seating and powder reduction.

[Pigdog]

hi guys got some questions for the experts here. Looking to try some 130berger vld in a 6.5x47l and thinking about trying the soft seating method and have a few questions. I realise the main drawback of this is having to extract a live round however it seems to make sense to use the bolt to seat the bullets the same amount every time. I realise this causes increase in pressure I have read anywhere from 10-20% so my questions are.

1.)Has anyone verified for example in a 6.5x47 how much reduction in powder they had to use when soft seating to allow for the pressure spike. Lets say you are using 36g varget (max recommended by berger) with a 130vld seated off the lands, how much have you found you had to reduce powder by when soft seating this same bullet?

2.)since you would now reduce the powder load to reduce the pressure when soft seating are you better off going with a powder like H4350 to ensure the case is "fuller" compared to varget

3.)Now that the powder load is lower with soft seating are you loosing velocity or is the fact that the pressure would still be the same compared to the off the lands load going to result in similar velocity?

4.)Are there any other drawbacks other than removing bullets or not fitting a mag, ie does soft seating cause more throat erosion or is brass going be ruined quicker (I wouldn't think so if you are reducing the load but there may be other factors at play that I'm not aware of if soft seating.

thanks

 

[watercam]

Personally I would drop 1 - 1.5 full grains and work back up to the velocity you had when jumping or what ever is most accurate. .005" is enough jam to allow soft seating. Don't let your neck tension get too heavy.

 

[gotcha]

Personally I would drop 1 - 1.5 full grains and work back up to the velocity you had when jumping or what ever is most accurate. .005" is enough jam to allow soft seating. Don't let your neck tension get too heavy.

I seat .010" to .015" longer than "touch" and .0005" neck tension with excellent results. I must be EXTREMELY consistent with bolt closing stroke to ensure consistent seating depth. For me, a .015" jam with .002" neck tension produces the same accuracy result W/O the hassle. CBI BBL., Min. spec. PTG reamer. ............... The "soft seat" goes all the way back to the Black powder cartridge days. Fun to experiment with but, not too productive in modern fire arms. JMHO

 

[4xforfun]

It won't cause any more PSI than a hard jam into the lands with normal loads.

 

[Pigdog]

thanks guys, anyone care to comment on question 3 and 4