SLUGS with "tail" wads at MACH??

[Vettepilot]

So, I'm playing with the relatively new various Russian slugs that I can now cast, that use a "tail" wad that stays with the slug during it's flight. I am also using some of those, or similar tail wads, in some experimental shells I'm playing with. I have a question about those, and flying them above the speed of sound.

First, let me mention that there is no manufacturer load data for these slugs, so no help there. Most slug load data has them flying at over the speed of sound. However, that might not be feasible when using these wad systems I'm thinking.

These slugs, with their wads that fly with them to the target, are stabilized by the wad. Meant to be shot in smooth bores without rifling to stabilize the slug, they instead use the wad to aerodynamically stabilize things.

But therein lies a problem. At the speed of sound, a shock wave forms off the head of the projectile, and whatever airflow there is around the payload at that point could not be counted on to flow by the wad to aerodynamically stabilize the package. At least those are my thoughts.

So with the above in mind, I'm thinking that these slug/wad together setups would necessarily have to be loaded subsonic if reasonable accuracy is to be expected. Which of course, is the whole point to begin with!!

Another angle might be I suppose, to use a rifled choke to stabilize the wad/slug during the supersonic portion of flight, with aerodynamic stabilizing taking over via the tail wad, when the whole mess drops subsonic.

The idea here is being able to use a smooth bore to shoot slugs accurately, when you don't have and can't get a rifled barrel.

Comments, thoughts, and ideas/theories highly welcome.

Vettepilot

[kycrawler]

Your over thinking it. They shoot fine at 1400 fps. Just load and send them

[armoredman]

May I see a picture of one? Never heard of these.

[Shawlerbrook]

If I am not mistaken some of the Brennekke slugs used to have a fiber wad attached to the base.

[longbow]

I am no expert on aerodynamics but I believe the shockwave comes of the nose at subsonic velocity and moved back to the tail/tailwad at supersonic velocity so that may help stabilize the slug.

Whatever, to my knowledge they work just fine at supersonic velocity. Best to look up Blood Trail's threads on the Russian slugs. Most have either plug-in or screw on attached wads. BT has posted accuracy results along with velocities in his threads.

Yes, Brenneke, Gualandi, Benco-Vitt and other factory slugs have attached wads of various types from felt to modern plastic fins and again, to my knowledge velocities tend to be supersonic and with good accuracy.

Here is a link to the Brenneke Classic slug info:

https://www.brennekeusa.com/hunting-ammunition/classic-magnumtm/

Definitely supersonic.

And Gualanid info:

http://www.gualandi.it/en/products_slugs/borra_proiettile.html

Also supersonic.

So, supersonic or not the attached wads work.

Longbow

[megasupermagnum]

With the exception of rifled foster slugs, just about all other slugs that shoot good from a smooth bore use a wad to stabilize. Brenneke, Lightfield, BPI's AQ and DGS designs, they all use a wad attached to stabilize. They also all work great at supersonic speeds. The most extreme example I can give is BPI's LBC sabot slug, which I used to shoot at a 2000 fps muzzle velocity. They shot really well, even out to 200 yards. Not hunting good, but fun anyway. Probably around 8" groups at 200 yards.

There is no doubt that a wad attached slug design can shoot really well over a wide range of speeds. There is one huge drawback to them though, and that is that it destroys the aerodynamics. Inside of 75 yards, no care at all. If you were hoping to stretch it out to 150, well it's a tough road. Generally a round ball is more aerodynamic than these. For example, a .735" ball has a ballistic coefficient of around .100, which I've found to be correct from my own shooting. By comparison, that LBC sabot slug at 2000 fps, I calculate to have a BC of about .05, about the worst that I've ever seen from any bullet ever.

[Cap'n Morgan]

Most of my slug shooting has been at subsonic speed. My Brenneke copy would show slightly oval holes at 100 yards, but perfectly round at 50. This would indicate that the tail wobbling gradually increases during flight. Somewhere, I read about a von Witzleben "Bolzengeschoss" - which had a fairly long wooden wad, which you could actually see wobble in flight.

Wadcutters, with their flat noses, are notorious for becoming unstable in flight, and even start tumbling at some point as the shockwave does its thing. If anything, supersonic slugs may be more stable in flight, as the drag/shockwave is more smooth.

http://www.aerospaceweb.org/question/aerodynamics/q0074.shtml

[gpidaho]

I may have missed the point but I didn't get the memo that attached tail wads were just for smoothbores. I shoot the Russian paradox slug with the press in tail wad from my Ultra Slugger and it seems to fly pretty well. Gp

[Vettepilot]

While I think that in many parts of Europe they (have to??) shoot slugs out of smooth bores, I don't think these are advertised as being "smooth bore only", and I didn't mean to intimate that. That's just my personal situation. I have three 12 gauge shotguns, and cannot find a rifled barrel for any of them. Well, a rifled barrel shows up for my Winchester 1300 every once and a great while, but usually for $250 to $300, which I am unwilling to spend.

Thanks for the answers guys!

Vettepilot