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I've been contemplating getting a digital scale, but after reading about the reliability woes of them, I think I'm better off sticking with the beam scales. Thanks for the heads-up!
 

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Just a plinker here, not measuring velocity or measuring in tenths of a grain; just glad when I don't shoot a squib.

I came to mistrust digital scales, but that's me. I sold my RCBS after it broke and the company sent me a new one. I didn't like the warm-up period or trust that readings would not drift after a bit.

So many others have had great success with digitals, so use what works best for you. I zero my beam scale each time, check charges during loading, and have not gotten any other problems since. That said, "since." I'm Type-A and always re-checking everything.
 

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Electronic scales can be affected by being to close to fluorescent lights. also having anything else on the same extension cord
 

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I'm not a fan of digital scales either. Too inconsistent and any perceived efficiency is wiped out by the constant need to keep checking the accuracy. Accuracy with any instrument is the direct result of money. If you spend enough money you'll get an accurate instrument. There's a reason a quality beam scale costs about $100 even though it's a relatively simple device. I'm sure if you threw enough money at an electronic scale you would get a very precise instrument but that's not gonna happen for $25-50. YMMV.
 

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Discussion Starter #26
JLS1980, A little known fact about non-temperature compensated powders …. virtually all these powders will burn faster in a hot chamber, however sometimes it does exactly the opposite of what you might think …. especially slower burning powders with heavier bullets. Because they burn faster, chamber pressure elevates faster so more powder gets burned up in fewer inches of bullet travel. The end result is a slower muzzle velocity, not faster. I have never used R-19 so I don't know how it behaves …. maybe heat could have been the cause …. but I can't explain the last shot???

Regardless, I still don't think your scale was responsible for your velocity variations, even though I prefer scales accurate to .1 grains. I think it was your choice of powder. R-19 is pretty slow burning, virtually the same as IMR 4831, which is intended more for larger capacity cases. When I owned my Rem 700 chambered in 7mm-08, I tested several powders and bullets to see what worked best. I settled on Speer 145gr bullets …. heavier bullets just didn't group as well nor chronograph as tight plus they left the muzzle at a slower velocity with an inferior trajectory. I tested many powders and found any powder that burns slower than IMR 4350 just didn't chrono very uniform in my 7mm-08. R-19 is much slower burning than IMR 4350 so I think it is just way too slow for your 7mm-08. My goto powder for my 7mm-08 was Varget. 41 grains chronoed a 145gr bullet (Speer Spitzer Boattail Soft Point) in excess of 2700 fps with exceptionally good accuracy from a hunting rifle.

If you look at the burn rate chart, you will see Varget is #101 in the order of burn rate whereas R-19 is rated at #123, a much slower burn rate. Reloading manuals can tell you a lot too. In this case, the amount of powder needed for a given velocity with the same bullet gives you a clue about burn rates where a heavier powder charge means the powder is burning slower. According to the Speer manual (#14) R-19 requires 47 grains for 2692 fps with a 145gr bullet. The same bullet with Varget requires 41 grains for 2707 fps (very close to R-19's 2692 fps).

Using QuickLOAD with a Speer 145gr bullet, it takes 14.1" of bullet travel to reach a 95% burn with 41gr of Varget. R-19 takes in excess of 24" of bullet travel to reach a 95% burn with 47gr of R-19. At 22" of bullet travel (24" barrel) velocity is very close for both 2688 fps for R-19, 2695 fps for Varget. 41gr of Varget fills the case to 93.4% of capacity whereas 47gr of R-19 fills the case to 103.6% …. slightly compressed.
You got me curious lowegan, what does QuckLOAD say about how much bullet travel is needed for full burn using the 160 grain speer hot core instead of the 145 grain? I found the reason for crazy #'s by the way, when I pulled the loaded rounds after noticing run out, not all case mouths were sized correctly, some came out way to easy. Resizing all of them fixed that and velocity stabilized from 2670-2680, rifle grouped at 1.25" 3 shot. That's using the lee balance beam for all loads as well.
 
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