Thought this may be of help to folks looking at the Gem Pro and alternatives. Been using a 505 for a long time and a Gem Pro for about a year now. Both are great, but I find myself mostly using the 505 to weigh charges, and the Gem Pro as a double check. I found that with the method below I can trickle faster on the 505 than the GP. Not by much, but a bit.
I read online somewhere of a gent in the UK I believe who modified his 505 for accuracy and rigged up a web cam to view it. Sorry, can't for the life of me find the link now. Anyway, I went out and bought a webcam, cracked it open and adjusted the focus down to a half inch or so. It sits on a cartridge box pointed at the beam end. The gent in the UK had rigged up an extended pointer on his scale for more precision but also had to rebalance it. A piece of painter's tape across the screen instead serves as a precise reference line for better consistency, as the extended pointer would. Let the scale come to rest at 0 weight and place the tape across the screen in line with the pointer. Done. It obviously doesn't matter this way if the beam is zeroed against the line on the scale body, as your tape line is the reference, but I do it anyway to line things back up in case I bump anything.
Using this method, I dump the rough thrown charge in the pan, let it settle and trickle the last few grains in till the beam line comes up to the tape line. Usually it's only a half dozen grains or so, so this is very quick. Smooth too as you see the pointer slowly rise on the screen. I've found this is a little bit quicker than dumping the rough charge into the Gem Pro pan trickling a few, weighing again and then waiting for it to settle.
The 505 is advertised as having +/- 0.1 grain accuracy,
and the Gem Pro as +/- .02 grain accuracy. I have found this not to be the case; my experience is that the 505 is exactly as accurate as the Gem Pro when used this way. All charges comes out dead nuts on target when double checked on the Gem Pro. The 25.0 grains here was weighed out on the 505 seconds earlier, and came out exactly on target. Every time I think I've weighed a 24.95 for example it turns out the Gem Pro drifted a bit.
Both scales are great, I recommend either, or both, highly. I definitely prefer the Gem Pro for weighing cases or other things, where it's just one weighing and there's no bringing up to weight involved; it's much quicker than messing around with the .01 grain weight on the 505 and waiting for it to settle. So, in summary I guess you could say for weighing stuff, the Gen Pro is the winner. For getting stuff to a weight, my nod goes to the 505.
I read online somewhere of a gent in the UK I believe who modified his 505 for accuracy and rigged up a web cam to view it. Sorry, can't for the life of me find the link now. Anyway, I went out and bought a webcam, cracked it open and adjusted the focus down to a half inch or so. It sits on a cartridge box pointed at the beam end. The gent in the UK had rigged up an extended pointer on his scale for more precision but also had to rebalance it. A piece of painter's tape across the screen instead serves as a precise reference line for better consistency, as the extended pointer would. Let the scale come to rest at 0 weight and place the tape across the screen in line with the pointer. Done. It obviously doesn't matter this way if the beam is zeroed against the line on the scale body, as your tape line is the reference, but I do it anyway to line things back up in case I bump anything.
Using this method, I dump the rough thrown charge in the pan, let it settle and trickle the last few grains in till the beam line comes up to the tape line. Usually it's only a half dozen grains or so, so this is very quick. Smooth too as you see the pointer slowly rise on the screen. I've found this is a little bit quicker than dumping the rough charge into the Gem Pro pan trickling a few, weighing again and then waiting for it to settle.
The 505 is advertised as having +/- 0.1 grain accuracy,
and the Gem Pro as +/- .02 grain accuracy. I have found this not to be the case; my experience is that the 505 is exactly as accurate as the Gem Pro when used this way. All charges comes out dead nuts on target when double checked on the Gem Pro. The 25.0 grains here was weighed out on the 505 seconds earlier, and came out exactly on target. Every time I think I've weighed a 24.95 for example it turns out the Gem Pro drifted a bit.
Both scales are great, I recommend either, or both, highly. I definitely prefer the Gem Pro for weighing cases or other things, where it's just one weighing and there's no bringing up to weight involved; it's much quicker than messing around with the .01 grain weight on the 505 and waiting for it to settle. So, in summary I guess you could say for weighing stuff, the Gen Pro is the winner. For getting stuff to a weight, my nod goes to the 505.
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