I have just sniveled a case of S355, and want to start using it in my 9,3 with both 286grn and 270grn bullets. Since Somchem nolonger issue data sheets....does anyone have any experience with this power in this round?

http://www.somchem.co.za/ Some data here for the 9.3x62 might help ?

Hi Linren

Unfortunately Somchem haven't updated their website in the last 5 years...And have introduced several new powders for which no data is available. Got 22lbs of 355 which, in theory, is equivalent to Aliant Reloader 15 and a better powder for this round than S335.

Will just have to start at 57grns and work up!

/

Some data taken from QuickLoad although the OAL and barrel length are just guesstimates.

S355, 60.0 grs for a Speer 270 gr.

S355, 56.0 grs. for a Nosler Partition 286 gr.

Ought to get you started, anyway.

Loading reductions & precautions apply.

Loadtech gives the following.

286PT 54-60 grs
270 Speer 55-61.5grs.

Ganyana,
From the Africa Hunting Info web site

for S355
320 grain Bullet; 53.0 - 55.0
300 grain Bullet; 55.0 - 58.0

Thanks Guys

Loaded up a bunch of Woodleigh 286grn solids, stewart softs and speer 270grn and will chrono them this afternoon. I'll post results so that the guys with fancy programmes can see how close they are!

Ganyana

I emailed Somchem and they gave 59.3 as max, loaded 60 grains behind a 286 grain proam and claw bullets, got 2380 fps

Hoep this help

Ganyana,

I have tried many different loads with my 9,3 x 62 mm. I have settled on S355 only because I do not need all the velocity that can be had from the case, and in so doing I reduced the chamber press as well. S341 will yield higher velocities than S355, if you so desire. With lighter weight bullets in the caliber, such as 230/235 grainers, I found that S335, a quicker burning powder, is better to get a complete powder burn.

Bear in mind that 9,3 cases differ from 73.5 grains to 77 grains of water capacity, depending on which brand you are using. PMP hold the least amount of water, Lapua hold 75 grains and Norma 77 grains. So that can also play a role in your final velocity achieved. If you want more velocity, obviously one has to opt for Norma cases that can take more powder.

I have tested S355 with Lapua cases, with std primers, between 56 and 58 grains in 3 different rifles (Husky, CZ550 & Custom K98) - COL = 85 mm. Due to differing barrel tightness and barrel lengths, we got different velocities as can be expected. I got 2,220 fps in my rifle (23,62-inch or 600 mm)) with 56 grains, whereas another rifle needed 57 grains to get the same velocity. The CZ550 with its 25-inch tube averaged about 80 fps more than my Husky.

With a VC factor of 39.64 then, you can easily expect about 2,300 fps with 58 grains of S355, and still be under Somchem's max of 59.3 grains. 59.3 would most probably be a compressed load with a PMP case, being the smallest of the lot. Lapua cases are scares, so I bought a lot of 200 Norma cases recently.

Just for interest sake, the BASA load, is a compressed load of 61 grains with a slower burning powder, S365.

Two more points to note about calculations with QuickLoad:

1) The water capacity is overstated at 78 grains - adjust to the capacity of the case that is to be used (73.5 or 75 or 77).
2) It over calculates the velocity - I got 2,220 fps whereas the program calculates 2,346 fps for my specific load as mentioned above - an over-statement of 5.7%

Chris

Thanks guy's - Flip how do you get Somchem to answer? Chris- had funny pressure spikes with 341 and went to 335, but managed to get 5kgs of what should be a better powder.

Norma Brass, CCI 250 magnum primers, 24" barrel,
Woodleigh 286grn Solid, seated to cannelure (82mm). Air temp 36°C (97F)

58grns = 2341fps
58.5grns = 2360fps
59 grns = 2390 fps

at 59grns the load is just compressed with the solid. Using woodleigh softs (loaded to 82mm oal)the load is not quite compressed.

Ganyana,
A tip I got from wink, is to vibrate your cases on your tumbler, it packs the powder closer and you do not have a compressed load. Especially the S4__ range of Somchem does not like it to be compressed.

I'm also thinking of changing to S355 from S335 for my 375.

Jaco,

I'm getting excellent results with S355 in my .375: W-W cases, CCI200 primers, 69,0gr of S355 and a 300gr Rhino bullet. This gives me 2450fps, with consistent MOA groups. Well worth a try - naturally you should work up to that load.

Rikkie,
Is there a reason why you use CCI200 instead of CCI250. Just curious, I have always used CCI250 in my 375.

If this powder is equivalent to RL-15, then 57.0 grains should see you right.

LD

Jaco,

No reason, except that I like to standardise components (and buy in bulk), and I've never found a real need for a mag primer. Even with ball powders like S341 (in my .308) the CCI 100 does just fine, although I have tried CCI 250 there. Can't say I saw any difference.

quote:

at 59grns the load is just compressed with the solid. Using woodleigh softs (loaded to 82mm oal) the load is not quite compressed.

With S355, being a slower burning powder than S335, I found that a near full or a full case gave better results - ie, do not go below 56 grains if you want a complete burn. With Norma cases one can go about 2 grains up in the load for the same seating depth. The PMP case max out at 57 grains. I seat the bullet out further than the CIP 83.6 mm AOL, and since I do not crimp, I do not worry about seating the bullet to the crimping groove mark.

With S335 one can load very mild (2,180 fps), like some do, and still get a complete powder burn, unlike with S355. S335 is also more appropriate for the lighter bullets. A Solid at 2,180 will glide through most anything.

Chris.

Keeping playing!

Norma brass,
CCI 250 (mag) Primer,
woodleigh 286gn solid seated to canaulure (82mm)
temp 30°C.
59.3grns S355 = 2401fps (Max 2407, min 2398! Gave me a 1" group at 100m.
no measurable case head expansion

same load but woodleigh soft = 2440fps

Norma Brass,
CCI 250 primer
speer 270grn soft
82mm aol
56grns S355 = 2305fps (min 2301 max 2309)

This load was so accurate, I pushed the target back to 200m, and got a 26mm 5 shot group!

NB- With some Oldish RWS cases (don't fit in American Shell holders) I got over 100fps less with identical loads.