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Unobtanium
12-07-2017, 07:25 AM
Is there any work that has gone into transonic slug stability? This is a valid question, imo, because of the low-recoil slugs available to LE, today. They begin with a velocity barely over the speed of sound, and by 75 yards have gone fully subsonic. At 35-50 yards, they are passing through the transonic zone, which as we know can be a real havoc causer with rifle rounds. We care enough about slug accuracy to buy things and design things like the "Truball" slugs, etc.

Is the foster slug agnostic to the transonic barrier, or does it cause a measurable accuracy issue?

txdpd
12-11-2017, 12:44 PM
I always get better groups with low recoil slugs. That's because I'm taking less of a beating.

I don't think it'll make much of a difference with Foster Slugs, since they a primarily relying on their heavy nose and not spin for stabilization.

GJM
12-11-2017, 01:02 PM
I use Brenneke Classic Magnum slugs for anything worth shooting with a slug.

Hambo
12-11-2017, 03:34 PM
Is there any work that has gone into transonic slug stability?

I doubt it. For the most part hunters bailed on Foster slugs with the advent of rifled barrels and sabots. The ones who really want to shoot long range (for slugs) buy Savage 220s. A lot of LE agencies have moved on from shotguns altogether.

DocGKR
12-11-2017, 04:59 PM
Not that I am aware of, however, perhaps sometime we can remedy that.

On the other hand, a slug is already heavy at the front, so is quite stable when launched; it is also not typically spin stabilized in duty type smooth bores.

As long as you can get a good group at your common slug ranges of say 100yds or so, then I would not worry too much...

Unobtanium
12-11-2017, 09:03 PM
Not that I am aware of, however, perhaps sometime we can remedy that.

On the other hand, a slug is already heavy at the front, so is quite stable when launched; it is also not typically spin stabilized in duty type smooth bores.

As long as you can get a good group at your common slug ranges of say 100yds or so, then I would not worry too much...

I did my own testing the other day. Using hydrashok and federal dp slugs, I noted significant fleet yaw. This was expressed as slugs striking the target at 75 yards and creating holes that were not round. Remington sluggers did not exhibit this. Federal Truball low recoil likewise did not exhibit this as much. These two rounds were also the most accurate. It seems to me that fleet yaw and accuracy are tied together. The effect of transonic stability on fleet yaw, I am still looking into. I will have to shoot some near targets with the hydrashok, as they are still not near transonic at 25 yards, per my chronograph data.