unburned powder in barrel?

garybusey

Regular
Rating - 100%
3   0   0
Location
vancouver, bc
I'm reloading .38 auto and I started off with the starting loads which is 6.7 and am at 7.2 right now and max is 7.5 for blue dot powder. at 7.2 I'm still getting unburned powder left in the barrel of the gun. I'm guessing this means I need to be using more powder? I'll also try the same 7.2's again but seated closer to min oal and with a deeper crimp to see if that improves combustion. any advice is appreciated.
 
Doing things like crimping and seating deep will increase pressures. I don't know if this will significantly affect burn rate though. Looks to me like you just need a faster powder. Is your .38 compensated ?

"Dicking with computers has me temporarily without access to my "Quickload" program. Its a great tool for working out these sorts of problems. Windows 8 = Crap.
 
Oooh! A fellow CGN'r with Quick load! My quick load program is gone since my last crash :( and the operating system I use is no good for available quick load versions.........

Sorry for the hijack.
To answer the OP; more powder,crimp ing more, deeper seating, mag primers, heavier bullets, seatind deeper into case, +P cases, thicker cases (FC nickle plate), longer barrel, all will increase the pressure and the burn % of your powder.

However; you may want to also examine the possibility that there is too much powder to be burnt 100% by the time the bullet leaves the muzzle.

Even if there is a bit left behind its not a big deal as this does happen with varrious degrees to loads. Acheiving 100% powder burn is a difficult thing to do. Now that being said....how much is being left unburnt?
 
Last edited:
well its a tiny amount, seems to be only a few half burned grains. but when i tap them out of the barrel scrape them together and then put a lighter to them, it ignites. I've heard blue dot is a very slow burning powder and this is a common issue. I made up some new ones last night same charge but seated deeper and crimped deeper and then also made some higher charge ones so I'll see what happens.
 
ok tested the 7.5's tonite and they seem to have less powder left in the barrel. I checked out QuickLOAD and it says at 7.5 grains of blue dot the amount of propellant burnt is only 61%...so that kind of explains everything. I entered the proper data for winchester 231 powder and it says the amount of propellant burnt at normal charge is 99% I might purchase some of the 231 and try that.
 
Back
Top Bottom