Does shearing stick powder hurt the load?

[Spyguy]

I've been looking at the design and operation of powder measures like the RCBS Uniflow and it seems that they would shear (cut) some of the individual granules of stick powders as they are rotated to drop the load. Is this a problem?

[BigBronco]

I have never noticed an issue. One or two pieces of powder sheared out of hundreds. The percentage of variance is minimal.

[JMP]

The specific impulse of a powder is controlled in two primary ways:
1. Reduce the surface area of the powder
2. Use retardants to control the burn.

In the case of cutting the powder, you are increasing the powder's relative quickness by increasing the surface area for combustion. However, this example, the effect is negligible as so few granules are effected.

[Bastard]

get a charge master & don't worry about it.

or

you could come to the realization that what you should be thinking about is the inconsistencies in running stick powders through a powder measure - which bring me back to my original suggestion; get a charge master and don't worry about it.

[Spyguy]

get a charge master & don't worry about it.

I've expended the bulk of my reloading budget on some quality dies and other tools. A Chargemaster will come eventually, but not now.

you could come to the realization that what you should be thinking about is the inconsistencies in running stick powders through a powder measure

I have no intention of simply using a powder measure for throwing stick powder charges. Rather, the powder measure will be used to get me in the ball park and the rest will be trickled into the scale pan. All stick powder loads will be measured by weight.

[Che762x39]

I've been looking at the design and operation of powder measures like the RCBS Uniflow and it seems that they would shear (cut) some of the individual granules of stick powders as they are rotated to drop the load. Is this a problem?

No sir I have using the Uniflow for 30+ years. Not a problem, have fun

[BSlacker]

I compared uncut to cut by using a dipper and trickeled up compared to a Lyman 55 and a old Belding & Mull. The load was in a rifle. The Chrono showed no big difference in SD. If it worries you just dip to get close then trickle.

[Spyguy]

If it worries you just dip to get close then trickle.

I was wondering if dip & trickle was necessary, hence the question. But it would appear from the responses here that it's not.

[JMP]

I was wondering if dip & trickle was necessary, hence the question. But it would appear from the responses here that it's not.

No, trickles and such are a waste of time. Just use a shell case or something to drop a few more granules on your charge. A chargemaster is mandatory, IMO, for throwing large loads. But, for small sticks like Varget, it frequently throws a range of up to +0.4 grains. The chargemaster works well throwing spherical powders or large sticks like Retumbo since it'll be dropping one granule at a time when it's in its trickle stage. Work is still required on a chargemaster for little sticks. Also, you must frequently verify or recalibrate it if you rely on a throw from a chargemaster.

[mark501w]

I've had a trickler for years never used it ,even on cases as small as .380.

[Bumslie]

No, trickles and such are a waste of time. Just use a shell case or something to drop a few more granules on your charge. A chargemaster is mandatory, IMO, for throwing large loads. But, for small sticks like Varget, it frequently throws a range of up to +0.4 grains. The chargemaster works well throwing spherical powders or large sticks like Retumbo since it'll be dropping one granule at a time when it's in its trickle stage. Work is still required on a chargemaster for little sticks. Also, you must frequently verify or recalibrate it if you rely on a throw from a chargemaster.

+1 on all accounts. Great advice.

[3RDGEARGRNDRR]

This is whats known as power crunching. Anyone who loads 4064 on a progressive knows what i am talking about. The Uniflow is very similar to the lock n load dispenser. Just ram your way through a stick with the lever.
On a progressive i have had bent necks from the granules really getting stuck in the rotor but usually you can feel the resistance and tap the rotor to break the sticks to save brass and prevent a spill.

[thenodnarb]

I have had .6 grain variations with my uniflow using 4064. For plinking loads, I will accept this variation and choose a charge that is well below max.

I never used my trickler until recently when I wanted some really precise 7mm RM loads. I would through a charge that was close and trickle to it. This way my charge was as accurate as my scale. It really doesn't take too long. maybe faster than a charge master which can take 20-30 seconds to throw a charge that big. In the future, if powder is easier to find(hopefully) I plan to transition to ball powders for plinking loads. While they may be more temp sensitive, that is a lot more acceptable and predictable than a .6grain variation from an extruded. temp sensitivity is overrated IMO.

[meaty-btz]

I have had .6 grain variations with my uniflow using 4064. For plinking loads, I will accept this variation and choose a charge that is well below max.

I never used my trickler until recently when I wanted some really precise 7mm RM loads. I would through a charge that was close and trickle to it. This way my charge was as accurate as my scale. It really doesn't take too long. maybe faster than a charge master which can take 20-30 seconds to throw a charge that big. In the future, if powder is easier to find(hopefully) I plan to transition to ball powders for plinking loads. While they may be more temp sensitive, that is a lot more acceptable and predictable than a .6grain variation from an extruded. temp sensitivity is overrated IMO.

I transitioned to ball powder but on my uniflow.. I used H4895 (long grain) and while it munched one or two sticks.. they were never more than .1 off with the occasional .2 off due to me not doing the perfect repeat motion. I don't understand how people throw charges that are WAAAAAAAAAAY off. Mine is old, worn, and sloppy and I constantly have to re-tighten things. I was able to load over 50 rounds of 8x57 that had a STD-DEV of less than 10. That is pretty damn consistent. Now light charges of that powder were crap but 45+ grains dropped well. My motion had more to do with charge variation than anything else.

[thenodnarb]

I transitioned to ball powder but on my uniflow.. I used H4895 (long grain) and while it munched one or two sticks.. they were never more than .1 off with the occasional .2 off due to me not doing the perfect repeat motion. I don't understand how people throw charges that are WAAAAAAAAAAY off. Mine is old, worn, and sloppy and I constantly have to re-tighten things. I was able to load over 50 rounds of 8x57 that had a STD-DEV of less than 10. That is pretty damn consistent. Now light charges of that powder were crap but 45+ grains dropped well. My motion had more to do with charge variation than anything else.

I don't understand how it can be that far off either but it happens. usually when I am throwing loads to set up the PM, they will be fairly consistent, .1 or .2 off. But Then I'll throw 50 in a row in the cases, and check a few of em, and i'll find some that are WAY off. Usually overcharged. Almost never undercharged.