Think it will fly?

[Al]

Had a little lathe time today and this idea has been bugging me since seeing Edges sabots on the old board.

Sleeve is made from Delrin, .457 over the bands, .450 in the grooves, .150 thick base, bullet is a .375 Hornady 270gr with a .001 press. Idea was for the sleeve to stay with the bullet, so there are no slits.

dunno, only made one to see what it would look like.

[Richard]

Al.......Did you taper the forward edge of the sabot? If not, I would think there will a lot of resistance and velocity will drop off quite rapidly Aerodynamicaly?........... kind of lacking! No? The BC has got to be in the basement. But it looks good Hey, tinkering is fun.
Richard

[joe21a]

If every sleeve stayed on the bullet the same way every time, I guess it could be accurate. I also think that might be hard to accomplish. Have you tried to push it down the barrel yet?

[Al]

just a .02 x 45, I thought about blending it in after the fact.

not sure why that pic came in so small thou.

[Harley]

Al, it's pretty and I know you had fun, but I think it'd be like tying a parachute to the bullet, not to mention the amount of yaw I'd expect.

Harley

[Al]

Mar 27, 2009 16:37:30 GMT -5 joe21a said:

If every sleeve stayed on the bullet the same way every time, I guess it could be accurate. I also think that might be hard to accomplish. Have you tried to push it down the barrel yet?

Joe, not yet, that be a morning project.

I fixed the pic, duh.

[ET]

Al

Well you're off to a start on something anyway. Like your idea of horizontal rib approach that might ease loading with a firmer polymer coat. Four thin splits down the coat like a sabot and cut petals off a sabot to use the base under your design.

I think I better stop here before I take another bite on a sweet carrot offering. ;D

Ed

[fowlplay]

Al,
Looks good and I think it will work. It may not be a 300 yard bullet with the sabot attached but who knows. There are shotgun slugs that are shot with the sabot staying attached. Good luck.
Steve

[Al]

Mar 27, 2009 16:37:30 GMT -5 joe21a said:

If every sleeve stayed on the bullet the same way every time, I guess it could be accurate. I also think that might be hard to accomplish. Have you tried to push it down the barrel yet?

well, it pushed a tad harder then I wanted, I made the 3 bands .100 wide, think I'll narrow them up a bit and blend in the front of it to match the profile, maybe see if we have something softer for material.

I'll whittle out 10 later today and give them a whirl next time out.

[jims]

Al They look good, I would like to try something like that with 8 mm bullets in my .38 barrel but that as also Edges look pretty labor/machine intensive to me.

[rbinar]

8-)I'm not able to say for sure but let me speculate that
the sabot may not reach much down range even with the
press fit. I shot some sabots like the ones you have here
when working on getting a 375 bullet to work in 40 caliber.

I found that the sabot wouldn't make it to a 50 yard target.
I have also seen some targets where the sabot made impact
and I'm uncertain the difference.

It could be (this is a guess not a fact) the rifling has something
to do with the situation. The 40 has much quicker rifling than
most muzzle loaders and I wonder if the spin force may effect
what happens.

Whatever I'd like to see you shoot a few and see what impact
looks like.

[chuck41]

RB,
Is it possible that the spin forces that sabot to "open up" enough to release the bullet as soon as it leaves the barrel? With a bullet going about 2600fps with our 16" twist in the 40 that means it is spinning about 2000 revolutions per second. I suppose that would make for quite a bit of force on a piece of plastic.

Perhaps to insure reliable separation you would only have to slice them a tiny bit at the nose. We are used to seeing sabots that are slit all the way to the base, but with high velocity bullets and a 16" twist that might not be necessary at all.

[edge]

I think that the sabot will stay with the bullet even without the press fit!
The Base Drag will tend to glue the sabot to the base of the bullet.
When my sabot petals shear off the base follows the bullet for a very long distance. Non shearing petals would be an advantage, and delrin may hold a lot of promise in that area...if it is tough enough.

If you decide to saw petals into the sabot I suspect that 0.150 may not be thick enough to prevent drilling. If you have accuracy problems try a 0.250 thick base to see if that works. Then find the sweet spot that won't drill.

Ribs can be hard to load

If these are made on a CNC lathe, then I would suggest turning the base to 0.4500+-0.0005 and keep that dimension except the last 1/4 inch from the front.
Thread the front 1/4 inch with about a 0.020 pitch and a max diameter of 0.4590

Experiment with pitch and diameter to give the load pressure you are looking for.

I have found that a thread is more forgiving than rings, but you may find differently

edge.

[skin290]

Mar 27, 2009 21:02:36 GMT -5 fowlplay said:

Al,
Looks good and I think it will work. It may not be a 300 yard bullet with the sabot attached but who knows. There are shotgun slugs that are shot with the sabot staying attached. Good luck.
Steve

Yep...see "Sabot Pressure Wad" (Lightfield & Hastings)

also has a patent you can look up...

[Al]

Mar 30, 2009 7:43:34 GMT -5 edge said:

I think that the sabot will stay with the bullet even without the press fit!
The Base Drag will tend to glue the sabot to the base of the bullet.
When my sabot petals shear off the base follows the bullet for a very long distance. Non shearing petals would be an advantage, and delrin may hold a lot of promise in that area...if it is tough enough.

If you decide to saw petals into the sabot I suspect that 0.150 may not be thick enough to prevent drilling. If you have accuracy problems try a 0.250 thick base to see if that works. Then find the sweet spot that won't drill.

Ribs can be hard to load

If these are made on a CNC lathe, then I would suggest turning the base to 0.4500+-0.0005 and keep that dimension except the last 1/4 inch from the front.
Thread the front 1/4 inch with about a 0.020 pitch and a max diameter of 0.4590

Experiment with pitch and diameter to give the load pressure you are looking for.

I have found that a thread is more forgiving than rings, but you may find differently

edge.

Edge, they did push HARD, threads are my next try, but had to tear that lathe down this morning for a couple of days.

[rangeball]

I agree bc will be down from the original bullet, but I would expect it to be very near or even more than comparable full bore bullets of the same caliber. The overall length is longer, which will help.

This is something I've wondered about for a long time. The hastings non-discarding sabot shotgun slug is so accurate, why wouldn't this be.

Have you thought about ringing the sabot similar to the northfork bullets? I guess threading would be close to this...

I have my fingers crossed for you

[skin290]

Mar 30, 2009 10:55:42 GMT -5 rangeball said:

I agree bc will be down from the original bullet, but I would expect it to be very near or even more than comparable full bore bullets of the same caliber. The overall length is longer, which will help.

This is something I've wondered about for a long time. The hastings non-discarding sabot shotgun slug is so accurate, why wouldn't this be.

Have you thought about ringing the sabot similar to the northfork bullets? I guess threading would be close to this...

I have my fingers crossed for you

"Possibly"

Center of Mass...heavy lead part is fwd on the slug--light plastic is all the way back
On the pointy rifle bullet, heavy lead part is good in stock form, but you may have added on enough weight and at the right amount of distance back to change center of mass in a bad way.

How much is too much? I don't know, not an aerodynamics expert...but it COULD be a possibility. Then again, they may fly very well out of his gun. I am certainly not about to break out the equation book to find out (aero is like a black art sometimes).

[rangeball]

All good points, and very likely true.

But, it's not hard to type with my fingers crossed, so I'll continue to be optimistic

[ET]

Al

Kind of tried to put some more thought into your project.
One thought that comes to mind is the height of the delrin sleeve/jacket. The current height is above the straight wall or bearing surface creating a small tapered void between the bullet and sleeve that would allow air pressure to try to peel it off. I would think that if the sleeve height matched the bearing wall on the bullet with a streamlined taper it would have a better chance for survival accompanying the bullet down range.

Ed

[Al]

Mar 30, 2009 16:52:06 GMT -5 ET said:

Al

Kind of tried to put some more thought into your project.
One thought that comes to mind is the height of the delrin sleeve/jacket. The current height is above the straight wall or bearing surface creating a small tapered void between the bullet and sleeve that would allow air pressure to try to peel it off. I would think that if the sleeve height matched the bearing wall on the bullet with a streamlined taper it would have a better chance for survival accompanying the bullet down range.

Ed

Ed, that one I bored about .050 too deep, idea was to stop at the cannuler. Next time I make one, I'll taper the end 15* to streamline it in.

It may not fly worth a hoot either, but one never knows until he tries

[DBinNY]

I think it's time to shoot them.

[ET]

Al

I think we might be surprised with a double nosed (2-transitions) bullet. As to how far it will travel accurately will be interesting to find out.

That darn carrot is teasing me enough to look at some high density nylon with 300F resistance property. You may have seen it as V-blocks used to align small diameter pipe sections for fit-up. Can be nicely and easily machined. Don’t know yet if it can be found in round bar or hex bar shape and what diameters are available.
Just poking around for some info at the moment. ;D

Ed