QuickLoad

velvetant · Jul 8, 2010

Just wondering how accurate QL is.
do the charge weights/velocity work out?
I know every gun is different and to start low and work up.
DrMike did a QL for me that's way hotter than the VV manual Using VVN165 in my 25-06.

Just wondering since I've never used QL

Thanks

DrMike · Jul 8, 2010

Quick Load applies recognised physical parameters within a computer program to provide suggested charge weights of various powder/bullet combinations to produce pressures used to drive projectiles at various velocities. Because of lot-to-lot variations in propellants, primers, bullets and brass (to say nothing of varying effects from the use of differing primers), one must assume responsibility for using this data, just as you assume responsibility for any data.

Reloading manuals and guides provide data which has been tested in controlled laboratory settings; so long as you use the same lot number tested and the same components with identical lot numbers and the same test items, the data is reproducible. Otherwise, you are responsible to drop back to a safe minimum (many hand loaders recommend a ten percent reduction, and most will tell you you need at least a five percent reduction) and work up incrementally to ensure that you do not have high pressures. Quick Load is very accurate provided you understand the limitations.

Always drop back to a safe minimum when given a maximum charge, and work up carefully observing for pressure signs.

Interestingly, on many combinations, various reloading guides and manuals provide much higher charge weights than suggested by Quick Load. I just worked a charge yesterday that was taken from a powder manufacturer, and it was excessively hot. Quick Load had cautioned that this was a hot load, but I chose to test the load in any case because of the data provided by the powder company. Given the conditions under which I tested the data, the powder company gave me a hot load. Fortunately, I worked up from a safe minimum to verify what worked. The powder company was not wrong. However, I was responsible for my own actions.

No one should ever see a load and decide to charge a case simply because it was said to be "safe." Each hand loader is responsible to work up loads safely, recognising the very real possibility of changes in components and in burn rate of the propellant used.

Consequently, there is no data provided by VihtaVuori for 115 grain bullets, only for Speer 120 grain spitzer and Sierra HPBT, which have different bearing surfaces than 115 grain BT and 115 grain PT which I ran at your request. Moreover, the 120 grain PT is not a 120 grain Sierra HPBT; you would again have different bearing surfaces.

Stay safe and work up carefully.

velvetant · Jul 8, 2010

Nosler list 50.5 of VVn165 and QL says 57 with a 120 pt.
So I should start around 45gr for testing?
1 round each at .5 gr increments will be 25 rounds before I even start my 5 shot groups.
I guess that's why I'm asking about QL
maybe I should try the Ladder test for this powder/bullets
both the 115 BT and the 120 pt have shown to be very accurate in my rifle.

Thanks DrMike for the help

DrMike · Jul 8, 2010

I don't generally work in half-grain increments; rather my usual practise is to work with that volume of charge (anything between thirty and sixty grains) in one grain increments, which will be around 2% charge differential.

For whatever it is worth, I am extremely cautious when there is a discrepancy in data, opting usually to start at the minimum charge listed just to verify there are no pressure issues. It only takes a couple of times of catastrophic case rupture to get my attention.

There is another factor at play here. Speer is forthright in stating that they are working from a pressure maximum of 53,000 CUP, whereas QuickLOAD works with 65,000 PSI (4500 BAR), the latter being a considerably higher pressure. This is generally considered to be a safe pressure (witness SAAMI specs for the 270 WIN), though it is higher than the SAAMI pressure for the parent 30-06 cartridge, which is much closer to the CUP data used by Speer.