somchem S361 or S365 for 243win

[Nishon]

Hello guys! I'm setting up my 243 using the OCW method and I noticed that S361 produces more velocity than S365.I am setting up the rifle for long distance hunting so I could do with a little extra velocity.has anybody used S361 with CCI 200 primers?what were the outcomes and would you recommend it over S365 for a 243?

[Armand Steenkamp]

Nishon, S361 wil work best with a magnum primer like CCI250. Fed 215 or PMP.

Regards

[alecjohnson]

I mad euse of 361 in my 243Win. I always make use of magnum primers as I do not want to buy to many different primer types.

Now with 361 if you shoot in the same temperature all the time it is a great powder. With 365 you get great fluctuations from one lot to the next. but I can use same load in my 243 of (do not copy) 42.2gr 365 behind berger 88gr var for winter and summer. With 361 you will have more difficulty to get it to preform to your standards if different temperatures are present.

Then what bullet weight are you using?

[Nishon]

Thanks for the quick reply gentlemen.I'm using 100gn hornady interlock at the moment but I want to set up permantly with 95gn partitions.I will change to magnum primers preferably CCI250 as mentioned.Seems like S361 is the way to go then!

[Nishon]

Alec I'm using the OCW method and from what I understand that method is what is good for changes in temperature and minor variances in powder so I think it would help in the fluctuations you mentioned,I'm hoping it does.

[tripodmvr]

Alec I'm using the OCW method and from what I understand that method is what is good for changes in temperature and minor variances in powder so I think it would help in the fluctuations you mentioned,I'm hoping it does.

OCW is a very lengthy and cumbersome way of getting a optimum load. Read about QL and OBT and you will understand why that method is quicker and will achieve the same results in as little as 12 shots.

[Rudie]

Quickload just gets you there faster than OCW post your numbers and we might even save you some time

I have compared my data so many times to quickload by verifying it on a long distance ladder test and time and again the node i found with QL matches my ladder test or OCW for that matter.

I have used from S355 to S385 and everything in between including S361 in the 243 Win. S365 gives much better overall results in my rifle, it might be different in yours but as Alec mentioned S361 seemed temperature sensitive in my rifle as well . If you want to match a good batch to the 243 I wouldnt look further than Lot 76 S365. It burns slower than 74 and 71 and this is exactly what the 243 wants.

[Nishon]

Is QL and OBT a software programme or a method of load developement? Its the first time I'm reading of this.If it is another method could yourll be kind enough to explain it to me.

[Gian_dP]

Hi. Google Chris Long and OBT. Chris has developed a theory regarding the change of the crown due to the shock wave caused by the powder combustion. There are various accurate nodes as the shock wave goes up anx down the barrel.

Quickload is the software that yku usr to determine your barrel time. Fine tune load so that your barrel time coincides with an accurate node and load development is done. Experienced user will fire 5 bullets to callibrate QL and another 3 to 10 to fine tune. Much faster than ocw or ladder test.

[josh..]

Hey nishon .I tried s361 in my .243 went through two tins (had no 365)I never once managed to get a good grouping with various bullets .hornady interlocks ,interbond ,sierra varminters as well as pmp .once I got hold of 365 again that all changed . i got decent groupings straight away .that's just my experience so mess around maybe it works in ur gun .good luck .hope you come right

[alecjohnson]

Is QL and OBT a software programme or a method of load developement? Its the first time I'm reading of this.If it is another method could yourll be kind enough to explain it to me.

Ha I read through that you sent me on PM and I did not know that was the OCW method, I actually used it before I had a chronograph to develop loads for my 243.

Now I did get great results with my 243 making use of the OCW(I learnt about it from a friend that called it the trial method ).

Now I use QL it is much faster and cheaper to use. I figure out a load on QL that is safe, fire it over a chronograph, adjust Ql powder file to match my results, get a node and load it at that, shoot over crony again normally you have to recalibrate QL again as the volume changes therefore burn rate changes just to match up your setup. I have never( using QL ) needed more than 10 shots to get hunting accuracy constantly in my rifle.

So I know OCW works, but at the cost of bullets today and taking into account availability, It is very expensive, and I am very glad that I could make use of QL to work up an accurate load for my 375H&H with Barns TSX 350gr as I can not fire more that 12 shots with precision with that load as it hurts my shoulder of the bench after 6 shots, and by shot 10 I can feel I want to flinch and you cant do load development over shooting sticks.

works great on lighter calibers though expensive.


All you need for QL is

Caliber
Barrel length measured with bolt closed but firing pin back(tensioned) not factory length
use cleaning stick to measure
Cartridge volume in gr H2O of a fire formed cartridge
The bullet brand and weight to be used and product code if you have it (ex Hornady V-max 87gr #22440) jammer manne ek kon myself nie help nie
Powder type and if possible Lot number as it helps most QL users calibrate the burn rate faster.

The max COL of round were ogive is touching lands if possible
max COL that fits your mag
do not measure COL on ogive, measure the overall length

Primers to be used

And at least 2 different loads with the abovementioned components with speed measured over your chronograph


Now my recommendation is to use S365 and a magnum primer with the bullets heavier than 75gr Because That is what I would have used and because I use magnum primers in everything, if my 9mm Para would have been able to take LR primers I would probably be loading it with CCI 250 too.
that is my 2c worth for the day