So... just how,much chalk should I use? - Page 1

[ARCHIVED THREAD] - So... just how,much chalk should I use?

Posted: 11/28/2020 1:49:23 PM EDT

I’ve got Gregg’s CDs on the way. Have ordered up all the components and am ready to start building chalk rounds. Fill up the nose cone, leaving room to push on the zinc base? Halfway? Quarter-way?

Still haven’t received my LMT barrel - ordered on the 19th. Guess I’ll call LMT on Monday. Order status says “complete”... but no shipping info.

Thx, danbrew

Posted: 11/28/2020 5:14:38 PM EDT

[#1]

I fill them as much as possible, up to the zinc insertion depth.

Posted: 12/2/2020 7:31:01 PM EDT

[#2]

+1, More chalk makes a bitter puff

Posted: 3/28/2021 10:49:19 AM EDT

[#3]

i have to ask...does the weight really matter on the chalk rounds if you try to shoot these for accuracy? I rolled one and stuffed as much powder as i could. Out of curiosity i weighed it on a digital scale and it came out to be 244 grams (its a food scale, about all i have that can weigh a 40mm lol). I have a handful of preloaded chalks from CVDS i bought in 2019. For comparison, i weighed those too. Those had an average weight of 215 grams.

Posted: 3/30/2021 8:46:04 AM EDT

[#4]

Complete round should weigh 205g according to manuals. The orange dye powder in factory rounds is much lighter than chalk you get at Lowes. This weight is to match M406 or M381 type projectiles (.503lb). The M433 weighs .507lb... So... close does count in grenades. Since the 781 is designed to match the trajectory of those types of grenades, unless you are sighting in your 203 to fire HE, end projectile weight is not that important. GROG

Posted: 3/30/2021 2:07:49 PM EDT

[#5]

Quote History

Quoted:
Complete round should weigh 205g according to manuals. The orange dye powder in factory rounds is much lighter than chalk you get at Lowes. This weight is to match M406 or M381 type projectiles (.503lb). The M433 weighs .507lb... So... close does count in grenades. Since the 781 is designed to match the trajectory of those types of grenades, unless you are sighting in your 203 to fire HE, end projectile weight is not that important. GROG

View Quote

Im tracking now, i appreciate the insight Grog!

Posted: 3/30/2021 2:15:50 PM EDT

[#6]

As much as the coroner would need if Amy Schumer is ever murdered.

Posted: 3/30/2021 3:35:33 PM EDT

[#7]

What else have people tried in these rounds beside chalk that is eco-friendly and works?
e.g. Diatomaceous Earth?
Flour?
Borozin powder (Zinc Sterate)?
Powdered Sugar?

Posted: 3/30/2021 5:20:34 PM EDT

[#8]

Well... if you have access to an open field full of snow, try Holi powders. Multi colors, environmental safe. I have a box loaded up sans Oddball (they paint pretty pictures). Unfortunately the snow melted before I had the idea. Enjoy! GROG

Posted: 3/30/2021 5:48:41 PM EDT

[#9]

Quote History

Quoted:
Well... if you have access to an open field full of snow, try Holi powders. Multi colors, environmental safe. I have a box loaded up sans Oddball (they paint pretty pictures). Unfortunately the snow melted before I had the idea. Enjoy! GROG

View Quote

Interesting - those seem to be constarch-based
I'll def give that a whirl...

Posted: 4/1/2021 9:47:13 AM EDT

[#10]

Quote History

Quoted:
Complete round should weigh 205g according to manuals. The orange dye powder in factory rounds is much lighter than chalk you get at Lowes. This weight is to match M406 or M381 type projectiles (.503lb). The M433 weighs .507lb... So... close does count in grenades. Since the 781 is designed to match the trajectory of those types of grenades, unless you are sighting in your 203 to fire HE, end projectile weight is not that important. GROG

View Quote

A thought occurred to me...do chalk rounds have stability issues if there’s an air cavity in the nose cone? If i were to get an overall 205g weight, im obviously putting less of the Lowes chalk powder than i did on my last round i filled up to 244g.

Posted: 4/1/2021 10:37:52 AM EDT

[#11]

I ordered some pink "chameleon powder" for our gender reveal. It must be corn starch based because it burned quite well when mixed with air.

But it is the lightest, most fluffy colored powder I've ever seen. I'm gonna try some out with 40mm rounds soon

Posted: 4/1/2021 12:19:02 PM EDT

[#12]

Had 12 made, tested some today, did a video. Conditions were less than ideal, with muddy field, but got a few to pop. Will probably locate, clean, and refire the ones that did not break. All functioned as intended, and were the same impact area as factory sighted 781s. The "poof" was a little less than the orange factory air float dye. At least it gives you color options. Working on video editing, and will post a link when finished. GROG

Linky: Video

Posted: 4/2/2021 1:44:32 PM EDT

[#13]

Appreciate the video Grog

Posted: 4/25/2021 3:10:57 AM EDT

[#14]

Ghost pepper powder ......

Posted: 4/25/2021 11:11:44 AM EDT

[#15]

Here ya go: https://www.ghost-powder.com/ghost-pepper-powder.html

Posted: 4/6/2022 5:47:32 PM EDT

[#16]

Whats not eco friendly about chalk?

Posted: 4/7/2022 9:54:36 PM EDT

[#17]

Chalk is eco-friendly
I asked the question because I wondered what else was worth trying….

Posted: 4/8/2022 2:12:25 AM EDT

[#18]

I'm not sure chalk weight would cause instability when using a metal pusher but it certainly is possible.

I am using fully 3D printed projectiles, which means the chalk is a much larger proportion of the total weight and thus I suspect loose chalk may cause instability. Thus I am beginning to do two things. I have designed a nose cone that has a hollow front so as to reduce the amount of chalk required to fill the cone. The cone is also shaped to help move the chalk to the outside edge of the cone. The other thing I am experimenting with is to compact the chalk into the nose cone. I built a plug I can use to compact the chalk.

Posted: 4/10/2022 9:33:50 PM EDT

[#19]

Quote History

Quoted:
What else have people tried in these rounds beside chalk that is eco-friendly and works?
e.g. Diatomaceous Earth?
Flour?
Borozin powder (Zinc Sterate)?
Powdered Sugar?

View Quote

I tried Zinc Sterate.

The cloud lingers better than Chalk. But is not as visible as Chalk. Mixing it with Chalk did work well.

Not worth the cost when bulk chalk for construction is much cheaper.

Posted: 4/11/2022 2:27:07 AM EDT

[#20]

Anyone tried flour? It is WAY cheaper than chalk and being white should be fairly visible.

[ARCHIVED THREAD] - So... just how,much chalk should I use?

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