Grommets yes another stupid round ball question

[49FMarlin]

I need to go to the hardware store and get me some rubber grommets for my airlocks on my Mead bottles
and got to thinking,

what "IF" I found a rubber grommet or even a rubber "O"-ring that fit inside the Windjammer ? and set the roundball on top of it ?
with a 16Ga. hard card under the rubber grommet
the hole in the grommet would center the ball,
,
but wondering what would happen to it under the firing pressure?
im sure it would flatten out and push out, but that would also create a seal ?
or too much of a seal?

cheers
john

[Tatume]

Try it.

[MrWolf]

Wouldn't it melt and cause issues or are they heat resistant enough for that brief period?

[longbow]

+1 for try it.

If it is inside the shotcup it will not be exposed to any significant gas pressure and no heat. There's always a little blow by but not enough to do damage.

If you can find a grommet with a small enough hole and thick enough to center the ball... and they are cheap enough, then no reason not to give it a go.

I wouldn't stack them though if the hole isn't small enough to keep the ball from poking through. Might not be an issue but the lower grommet might squirm and shift. Shouldn't be a safety issue but would likely cause poor accuracy.

Yes, the grommet will compress under the ball and that will cause expansion outwards. ~10,000 PSI under the payload puts lots of stress on thing and if lead will obturate, rubber most certainly will. Outward expansion will add to bore friction but it shouldn't be a lot. I wouldn't worry about the sealing from that pressure because the gas seal will catch most and the blowby will push through past the grommet "seal" where it pushes on the shotcup walls even if the grommet is below the slits.

Speaking from experience here, I once decided to try using some shotcups I had cut off gas seals I used under a hard card wad column for 0.735" RB's. So, I put wad slugs in those shotcups then loaded up using 2 nitro card wads over the powder and a 1/2" hard card wad then the shotcup and slug. Accuracy was very bad and recovered shotcups told me why. There was so much blow by that the shotcups were gas cut and burned. The petals were stretched and black. Those plastic gas seals stop an awful lot more leakage than I would have thought which is why if you look at old loading recipes pre plastic wad/gas seal, the powder charges tend to be higher than those using plastic gas seals.

Not sure if you read Ranchdog's Lee slug results where he decided that the cushion wads are a bad thing because the cushion compresses and distorts. He was having trouble getting the accuracy he wanted from rifled gun. So he cut the cushion leg off and used the slug in shotcup on top of a hard card wad column with nitro card wad over the powder and got amazingly good accuracy with no shotcup issues.

The differences between what he did and what I did:

- I used 2 3/4" hulls, Ranchdog used 3" hulls
- I used 2 nitro card wads over the powder and 1 hard card wad, Ranchdog used 1 nitro card over the powder and 2 hard card wads
- I used Win AA Red wad shotcups, Ranchdog used something better (I can't recall but not Win AA Red) ~ I find Win AA Red wads to be soft and not be suitable for slug loads I have tried.

But I digress. I just mention this to point out how efficient plastic gas seals are and since you are experimenting this info may be of used down the line.

Precision Reloading used to offer felt donut wads. Not sure if they still have them. BPI offers what they call a gas seal but it is for some police or military application and the "gas seal" has a 1/4" hole though it. Not sure if they would work as a donut wad due to small hole but it could be drilled out easily. I ordered some of these from Canadian BPI but somehow the order got mixed up and not completed. I will likely order some next time which is coming up quick... I am running out of supplies and virtually nothing available locally.

Anyway, if you can find a suitable grommet I'd say give it a try. I'd be inclined to drop the nitro card wad in, grommet in, ball in then use a buffer (like shot buffer or COW) and vibrate it in around the ball or put a small scoop of buffer in before the ball but you have to make sure the ball sits down on the grommet. The buffer will help support the shotcup and make a seat for the ball. Not necessary but I've found that buffer improves my RB loads.

Longbow

[gpidaho]

49FMarlin: I've been experimenting with X12X gas seals from BPI. Cutting the center out of the seal to form a donut wad. To early to say if it's much of an improvement. Your grommet idea is likely less expensive. Give it a try and let us know how it works. Gp

[Blood Trail]

49FMarlin: I've been experimenting with X12X gas seals from BPI. Cutting the center out of the seal to form a donut wad. To early to say if it's much of an improvement. Your grommet idea is likely less expensive. Give it a try and let us know how it works. Gp

Why not just buy the donut gas seals from BPI?


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[gpidaho]

BT: Every time I've tried to order the donut wads from BPI they show them out of stock. I have a few more things I need (want) I'll check again. Gp

[megasupermagnum]

If the gas seal on the Windjammer wad doesn't seal, nothing will. I'm not going to say it's a waste of time, but I would rate a rubber washer pretty low on things that might help accuracy. The problem is you need the ball to center itself, not the other way around.

As for what would happen to the rubber washer, it would just be smooshed wherever it fit. It wouldn't hurt anything, but it won't add any support to the wad either.

[longbow]

That's why I suggest the buffer. So the grommet centers the ball when inserted and the buffer supports the ball at firing. Things change shape when subjected to 10,000 PSI accelerating them out a barrel! I agree, rubber will squish and the ball will likely contact the nitro card wad under but if the ball is centered at firing the deformation of grommet and nitro card wad may keep it centered. With buffer, the buffer should form a seat and ensure the ball can't move when it sets back. My thinking anyway. I've found buffer to be a good thing under RB's in my loads.

Felt donut wads from BPI or Precision Reloading (if they have them) should be good and those plastic gas seals BPI lists:

https://www.ballisticproducts.com/HB12-12ga-x-8mm-Wad-Base-250_bag/productinfo/072HB12/

look interesting. I tried to order some of these but the order got screwed up and I didn't get anything.

Or you can make your own donut wads by punching or making a drill jig. Tommygirl posted pics of her quite simple drill jig a few years ago. Pretty simple to make one from common stuff.

I haven't tried donut wads but am thinking I should. Donut wads with buffer on smaller than shotcup balls might eliminate the need for patching to snug fit. Patching with paper and cloth work well but take time. A drop in donut wad and buffer would be easier if results are good.

Longbow

[Blood Trail]

Why not just sit the round ball here? I’ve got a bunch of these and just did a “function check”. Holds the RB center.

https://uploads.tapatalk-cdn.com/20200119/d46779ad378d7fc454feaf2295afdfb8.jpg


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[longbow]

That's the gas seal I linked to. Tried to order some from Canadian BPI and somehow they couldn't figure out what it was even though I used the part number. Never got them. That and some buffer and maybe with Teflon or Mylar wrap should work.

I think those are the same seals Uncle Dino uses under his swaged slugs. I was also thinking of casting slugs with a stem to put that seal on then rivet the stem for quick and easy Brenneke style slug.

They should make a decent donut wad though. IIRC they are only available in full bore 12 ga. though so petals would have to be removed from shotcups or custom wad columns built.

Longbow

[Blood Trail]

That's the gas seal I linked to. Tried to order some from Canadian BPI and somehow they couldn't figure out what it was even though I used the part number. Never got them. That and some buffer and maybe with Teflon or Mylar wrap should work.

I think those are the same seals Uncle Dino uses under his swaged slugs. I was also thinking of casting slugs with a stem to put that seal on then rivet the stem for quick and easy Brenneke style slug.

They should make a decent donut wad though. IIRC they are only available in full bore 12 ga. though so petals would have to be removed from shotcups or custom wad columns built.

Longbow

Dennis uses the donut seals.


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[longbow]

Yeah, you are right, I was thinking those obturator seals were the ones with the holes through. My mistake. I was looking at the same ones Uncle Dino uses not the ones you showed. Hadn't finished my morning coffee so my eyes weren't fully open!

Longbow

[Mike Robinson]

A few years ago I loaded some round balls in plastic wads. I bought some plastic tubing at the local hardware store and cut it into about 1/4” thick pieces to help center the balls. 5/8” or 3/4” od tubing should work. The 1/4” “ring” can be cut if necessary to fit inside the wad. Now, I just use the Lyman 525, and get 2” groups at 50 yards with my Mossberg rifled barrel.

[fcvan]

Some years ago, I bought a 69 RB mold and some wads for it. The wads are cupped on both ends so it looks like it is basically double ended. Before loading the RB I put in a scoop of corn meal, an idea from my early black powder days. Anyway, the cornmeal helps center the ball and help the ball out the IC barrel I shoot them through. I bought a roll crimping device for a drill press but have yet to pick up a drill press. Fold crimp has worked, I just want the look of the roll crimp with powder coated RB boolits. The final plan is to PC the boolits to bore diameter to tighten things up. For now, I can keep 5 on a paper plate at 50 yards, but hope to do better with PC and roll crimping. And yes, I plan on using the semi transparent hulls for this project. Well, that and multi-colored buckshot loads, my brother wants some that are layered Red, White, and Blue. Me, I kind of want some Zombie Green Buckshot. That and some yankee doodles as well. Hmm, jet black might look good too.