OzFclass

KHGS wrote:

plumbs7 wrote:

Longranger wrote:That looks somewhere north of 62000PS... Just a guesstimate though.

I respect Keith's opinion a lot ! That was in the middle of the afternoon at Gundy opm. It shot very well!

I will be keeping an eye on it and will back the load of as Summer comes . 2209 does seem a little temp sensitive as much as 2208 in my 308 between winter and summer . It is pushing the limit for a medium cartridge . Anyway don't want to turn this into another blog as there is already 5 pages else where, enough to put any enthusiast asleep. If u like , I'll keep everyone posted on the 7-08 blog about load and pressure!
Still over the moon with it !

On the same note some of the velocties that Ftr guys pushing 215's and the amount of powder behind those pills makes me shake my head with the lil 308 win. But they are very successful . Pushing the boundaries I guess!
Regards Graham Sells.

Graham, there are several issues at play when we set out to develop an accurate load in any cartridge. The first issue to always consider is one of safety!!!! That is not only the shooter's safety but that of those around you, this is in fact a responsibility of the reloader which must never be undertaken lightly.
Please understand I am not criticising you or anyone else who frequents this site. The pic in the discussion indicates to me that the pressure MAY be above safe limits with that particular case! The fact that the load shoots well is NOT an indication of safety, many HOT loads display outstanding accuracy which is testament to the flexibility of the powders we have available to us today & can lead the uninformed down the path to unwittingly overloading their ammo in order to "up" the performance. There is a rule in engine performance that nothing outpaces "cubic inches" the same rule applies to cartridges, if you want speed safely use a bigger case!!
The "strength" of your action is only that of your brass case which is around 70000psi CUP or roughly 80000psi Piezio, both rates of pressure measuring methods are in use today. American manuals mostly (almost always) use the CUP measurement & ADI use mostly Piezio measurements, both are used in their latest handbook depending on the caliber. One should NEVER exceed 62000psi Piezio or 54000psi CUP no matter how well the load shoots.
I & others have spoken before of multiple accuracy nodes, the trick is to choose the right node! This node will be somewhere around 59 to 60000psi Piezio, in this range you will achieve good accuracy, case life & barrel life & you will preserve your safety & your action life will be extended.
All powders are temperature sensitive!!! Adi powders are LESS sensitive than others, if the load is maximum as so many are, the sensitivity will be more evident. This is why the node I have referred to above is wider than those at higher pressures.
In my many years as a full time professional gunsmith I have inspected & analysed many blown up rifles & pistols, not to mention other types of "firearm incidents" believe me nobody wants to risk being involved in any of these by "pushing the boundaries". In over 90% of these "incidents" human error was to blame. Now before the "experts" decide to jump on me, these are my opinions only & are based on observations during over 55 years of reloading & close to 40 years of professional gunsmithing.
Keith H.