1st attempt w/ IMR TB

joneb · April 16, 2006, 03:22 AM

Well I'm loading .38 spl. 158gr LrdFp using a Redding mod. #3 powder throw w/ the pistol meter, all seemed well untill the about the tenth charge only 1/2 a charge in the case. I kept going, consistantly about every one out of ten charges was haft a charge

I took the powder break out of the reservoir tube and no change, then I switched to the rifle meter and it solved the problem, but the charge wieghts varied +or- three tenths of a grain.

stinger · April 16, 2006, 10:22 PM

I have had different results. I use the Pro-Auto Disk that came with my Loadmaster, and I think this is the most accurately metered powder I have ever used. And the results with 38 special loads have me going back to this powder again and again.

Hope your luck changes,

Stinger

jfruser · April 17, 2006, 11:56 AM

I have had terrific results with TB in .357mag & .44mag.

TB through my Uniflow:
http://thehighroad.org/showthread.ph...ght=trail+boss

TB in .357mag & .44mag:
http://thehighroad.org/showthread.ph...ght=trail+boss

Good luck with your development.

joneb · April 17, 2006, 12:21 PM

I think I'll try the pistol metre again and try a more assertive throw. Should I use the restrictor in the reseroir tube ?

**Unclenick** · April 17, 2006, 12:34 PM

Jibjab,

Pull the pistol metering thimble out and inspect it for burrs, oil, or anything else that may be in the way, just to cover this base. You can wipe the parts with denatured alcohol to be sure there isn't any oil present. You can then rub powdered graphite into its surface and the other parts with a patch. Just don't let a jag point or a bronze brush bristle sratch the surface. Wear disposable gloves to do this so you don't get rusting finger oil onto the degreased parts.

Be sure that when the drum is in position to receive powder into the measuring space, that you pull the handle just smartly enough that it taps against the drum stop. Now back it up a very short distance and tap it a second time and throw the charge. Learning to make the taps consistent is important. Re-measuring your throw weight after you start tapping is important because the powder will tend to pack a bit tighter in the measuring cavity.

Now the secret: The tapping itself will break up a powder bridge, if you have one. More often, however, the real problem is that people don't allow enough time for the powder to finish falling into the measure. Instead, the measuring cavity is fully exposed to the powder supply only briefly. Double tapping forces you to take more time as well as ensuring powder isn't hanging up. The fact the bigger cavity throws inconsistently is another sign of overly brief "hang time" in the powder accepting position, but also, possibly, of powder bridging during part of that time.

I have an experiment under way with my old RCBS measure and my Redding 30BR. I am applying a "permenant" lube of molybdenum phosphate to the parts to see if I get improved uniformity? The product I am using is Moly Fusion Oil. I'll post a thread if it works out?

Nick

joneb · April 17, 2006, 01:24 PM

Thanks Unclenick,
I'll giver another try, with the small diameter of the pistol metre and the nature of IMR TB I can see the powder bridging might the culpret, the tap might just be the ticket

April 16, 2006, 03:22 AM	#1
joneb Senior Member Join Date: December 10, 2005 Location: Central , OR Posts: 1,888	1st attempt w/ IMR TB Well I'm loading .38 spl. 158gr LrdFp using a Redding mod. #3 powder throw w/ the pistol meter, all seemed well untill the about the tenth charge only 1/2 a charge in the case. I kept going, consistantly about every one out of ten charges was haft a charge I took the powder break out of the reservoir tube and no change, then I switched to the rifle meter and it solved the problem, but the charge wieghts varied +or- three tenths of a grain.

April 17, 2006, 12:34 PM	#5
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,061	Jibjab, Pull the pistol metering thimble out and inspect it for burrs, oil, or anything else that may be in the way, just to cover this base. You can wipe the parts with denatured alcohol to be sure there isn't any oil present. You can then rub powdered graphite into its surface and the other parts with a patch. Just don't let a jag point or a bronze brush bristle sratch the surface. Wear disposable gloves to do this so you don't get rusting finger oil onto the degreased parts. Be sure that when the drum is in position to receive powder into the measuring space, that you pull the handle just smartly enough that it taps against the drum stop. Now back it up a very short distance and tap it a second time and throw the charge. Learning to make the taps consistent is important. Re-measuring your throw weight after you start tapping is important because the powder will tend to pack a bit tighter in the measuring cavity. Now the secret: The tapping itself will break up a powder bridge, if you have one. More often, however, the real problem is that people don't allow enough time for the powder to finish falling into the measure. Instead, the measuring cavity is fully exposed to the powder supply only briefly. Double tapping forces you to take more time as well as ensuring powder isn't hanging up. The fact the bigger cavity throws inconsistently is another sign of overly brief "hang time" in the powder accepting position, but also, possibly, of powder bridging during part of that time. I have an experiment under way with my old RCBS measure and my Redding 30BR. I am applying a "permenant" lube of molybdenum phosphate to the parts to see if I get improved uniformity? The product I am using is Moly Fusion Oil. I'll post a thread if it works out? Nick __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

April 16, 2006, 10:22 PM	#2
stinger Senior Member Join Date: November 6, 2001 Location: west texas Posts: 772	I have had different results. I use the Pro-Auto Disk that came with my Loadmaster, and I think this is the most accurately metered powder I have ever used. And the results with 38 special loads have me going back to this powder again and again. Hope your luck changes, Stinger

April 17, 2006, 11:56 AM	#3
jfruser Senior Member Join Date: April 6, 2006 Location: Texas Posts: 350	I have had terrific results with TB in .357mag & .44mag. TB through my Uniflow: http://thehighroad.org/showthread.ph...ght=trail+boss TB in .357mag & .44mag: http://thehighroad.org/showthread.ph...ght=trail+boss Good luck with your development. __________________ Regards, jfruser "Books and bullets have their own destinies."----Bob Ross

April 17, 2006, 12:21 PM	#4
joneb Senior Member Join Date: December 10, 2005 Location: Central , OR Posts: 1,888	I think I'll try the pistol metre again and try a more assertive throw. Should I use the restrictor in the reseroir tube ?

April 17, 2006, 01:24 PM	#6
joneb Senior Member Join Date: December 10, 2005 Location: Central , OR Posts: 1,888	Thanks Unclenick, I'll giver another try, with the small diameter of the pistol metre and the nature of IMR TB I can see the powder bridging might the culpret, the tap might just be the ticket