i am looking for specific load data for my 308win using rs52 minimum loads to max loads,my bullets are 150gr sst /155 a-max and 168gr a-max. want to use the least amount of powder as rs52 is double bases BUT hoping to reach 2600 fps with my 20" barrel .i have look on the rs powder web site but nothing i can realy use.it would be nice if the start load was accurate as powder is getting hard to get and realy would prefer n140 or better still h4895 but have to use what i can find!
rs52 powder in the 308win
- Thread starter ashray
- Start date
You can contact RS directly from their website and give them the details of your cartridge, barrel length, bullet type/weight and ask them if they have a load that will get you 2600fps
According to Quickload:
With a 150gn SST, 46.0 gn of RS52 gives an MV of 2655fps
With a 155gn A Max, 46.0 gn of RS52 gives an MV of 2648fps
With a 168gn A Max, 46.0 gn of RS52 gives an MV of 2654fps
You'll get a more accurate answer if you measure the water capacity of a few of your fired cases and use that number instead of the nominal 56.00 gn used by Quickload
Cheers
Bruce
According to Quickload:
With a 150gn SST, 46.0 gn of RS52 gives an MV of 2655fps
With a 155gn A Max, 46.0 gn of RS52 gives an MV of 2648fps
With a 168gn A Max, 46.0 gn of RS52 gives an MV of 2654fps
You'll get a more accurate answer if you measure the water capacity of a few of your fired cases and use that number instead of the nominal 56.00 gn used by Quickload
Cheers
Bruce
ChesterP
Well-Known Member
I use the lower energy RS50 and 44gr behind a 150 in my T3 308 gives me 2650fps. RS50 is re-labelled TR140 which is basically the same as vhit N140. I've found the loads to be interchangeable between them. RS52 being higher energy and similar density I might have expected a little more. Indeed, entering the data for the 24" T3 in the The BBT "P-Max" internal ballistics simulator, I get 46gr RS52 behind a 150gr bullet resulting in over 2800 fps and 50,580psi chamber pressure. 44gr yields 2697fps @ 43,300psi which is a mild load. This compares using the same specs but substituting for RS50 a 44gr load yielding 2631fps @43,450psi which is very close indeed to my own developed load data. RS state a starting load of 40.3gr and a max load of 47.1 gr for RS52 and a 150gr SMK. I'd start 3/4 up at about 44gr and go up in 0.4gr intervals to 46gr, then in 0.2 gr steps to 47 gr looking for pressure signs.
I use 42gr RS52 in my .308s with 180gr bullets and it produces a nice accurate, medium recoiling load.
ChesterP
Well-Known Member
Fair comment in which case RS 50 will be the safer bet. "42 to 42.2" is a strange comment if you haven't already tried the powder? As HandB has already stated that 42 gr in his rifle is an accurate load it may or may not work for you but to really find out, you'll need to find the harmonic node for your specific rifle and a 0.2 gr range is no range at all. You'll need to work up more than that to determine what works for you. Seems like you've already made your mind up but load development is just that. You'll have to develop the load through development over a "significant" range of at least 3 to 4 grains. Try the OCW method (Google is your friend)| to economise on shots. Just giving honest advice. FWIW, RS52 is more a single base with powder coatings to increase energy. It's actually a single base impregnated with Nitro-glycerine. Whilst it erodes barrel throats more than RS50, keeping loads in the sensible 42 to 45grain region shouldn't result in significant erosion but if at all concerned, you can sell that powder on with no loss and use RS50 for ease of mind but bear in mind also that "hot" RS50 loads will not be much easier on barrel life than moderate RS52 loads. You don't need a hot load though for the MV's you need. Your barrel harmonics will be the ultimate determinant of suitable MV for precision with your bullet choice. No shortcuts to development except using tried and tested recipes to get close. In your case, chasing 2600fps, RS52 is not the powder I'd use. RS50 or N140 every time for the 150 class of bullets.
Dauntsey guns have N140 in stock.
One on top of two
Well-Known Member
I use and have used RS 50/ RS 52 for the last 4 years . Along with N140
45 grains of RS50 from a 24” tikka using a 168 Amax or 167 lapua scenar will give you 2600 fps average
44.5grains of RS52 will give you a little over 2700 fps on a warm day
RS50 is a little better at handling temp changes / temperature tolerance a bit better .
RS 50 is the better choice for general use imho .
This is from my rifle , so you obviously have to do your own testing
45 grains of RS50 from a 24” tikka using a 168 Amax or 167 lapua scenar will give you 2600 fps average
44.5grains of RS52 will give you a little over 2700 fps on a warm day
RS50 is a little better at handling temp changes / temperature tolerance a bit better .
RS 50 is the better choice for general use imho .
This is from my rifle , so you obviously have to do your own testing
ChesterP
Well-Known Member
Agree about RS50. I tested it alongside the older recipe (now since improved) for N140 using 175grn TMKs. What was interesting is that the RS version had a very linear MV rise with load, even at ambient 22 degrees. N140 had a tendency to spike from a grain or so under max load, and spike quite alarmingly. I plotted graphs for each to visualise the differences better and you could almost run a straight line through the MV gains for RS50 whereas N140 rose steeply as load increased, plateaued, and fell back as case capacity was met. Pressures were higher but MVs were lower. I suspect the RS version used better temperature stabilisers but I found it the better powder yielding better MVs despite the two being supposedly from the same source. Vhit has now addressed the (excessive) spiking by making N140 more temperature stable in the past year or two. 44 to 45 grains of either in my rifle gives good accuracy and 2600+ vel with 150 to 170gr bullets or 43.5 to 44 with the 175s.
QuickLOAD defaults are WAY out for RS52. Used unchanged the results underestimate pressures and calculate far too high charges.
................ and that's from 167/168gn bullets, even if from a 24-inch barrel. Those charges / results are very much in line with my own experience of the powder.
I'd see RS50 as the better choice for a deerstalking load.
So far as RS52 in 308 Win goes, its charges and results are very close to those for Hodgdon VarGet, but my experience is that whilst it gives higher MVs than VarGet with top-end loads, pressure spikes at slightly lower charge weights, and can do so very quickly without warning.
ChesterP
Well-Known Member
I agree about QL..for some reason it doesn't seem to be reliable for RS52 loads. I only ever experienced spikes using RS50 when trying it with some 190MKs (not the ideal powder I know), and it went from fine to within a third grain more to way over pressure, flattening primers and leaving bolt face marks on cases. Needless to say it's not a load I'll be using again! For the 150's, I limited my loads to 44gr or slightly under and at that it was very well behaved whilst delivering more than ample accuracy.
Have you discussed the RS52 pressure disparity with either QL or RS?
Nope. If I did that for every powder I found 'out' on QuickLOAD, I'd spend my life doing emails. QL updates its default factor values every now and then, and they may well have changed in the latest v.3.9. Nitrochemie also has a good loads database for popular cartridges, and this must always be the backstop. QL is an excellent development and comparison tool, but must never be used as a sole loads authority unless when modelling combinations not covered in the manufacturers' pressure-barrel tested data, and in that case only with extreme caution. As with many modelling programs, the apparent detail and precision of the results, down to single psi pressure values here, can mislead people into taking it as 'gospel'.
I used 46.8gr of RS52 under 168gr eldm, from a 24” barrel. It gave 2885fps. So I imagine it would get around 2760 from a 20” barrel.
Shot from an unmoderated rifle, and a possibly enough extra recoil above 150gr to notice (though I could never be sure it wasn’t in my head).
It did make big holes in things.
I occasionally regret not having a .308 anymore.
Shot from an unmoderated rifle, and a possibly enough extra recoil above 150gr to notice (though I could never be sure it wasn’t in my head).
It did make big holes in things.
I occasionally regret not having a .308 anymore.
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