shotgun slugs - why no gas checks?

[H Wally]

Was doing up some 45-70 GC boolits and it got me thinking - is there a reason why we don't gas check shotgun slugs and run them down rifled barrels?

Rifled slug barrels are capable of good accuracy (relatively speaking), but require expensive saboted slugs. You can shoot plain rifled slugs out of them, but those lead badly from what I've seen.
Gas checking cast boolits works well for BP and smokeless cast loads, so why don't we see gas checked shotgun slugs?

 

[legi0n]

there's one certain way to figure it out: make some and shoot them

 

[yomomma]

There are a bunch of full bore slugs out there.

Im sure someones madeit a gaschecked one by now.

https://www.ballisticproducts.com/mobile/Green-Slug-12ga-729-375gr-15_box/productinfo/7000005/

 

[H Wally]

there's one certain way to figure it out: make some and shoot them

Looks like that's going to have to happen - just need to find an HR handi slug gun or something to test them in

There are a bunch of full bore slugs out there.

Im sure someones madeit a gaschecked one by now.

https://www.ballisticproducts.com/mobile/Green-Slug-12ga-729-375gr-15_box/productinfo/7000005/

That's neat - a copper jacket aluminium core slug... Seems odd they didn't go with a single-metal slug, though at $2/projectile they might not have a market if things cost any more.


I wonder if there's some issue around liability and chamber pressure spikes with the mass of a lead projectile engaging rifling rather than the plastic sabot material, and the chance that it could be used in an old-as-dirt and poorly maintained 12 gauge. IE, a lead slug directly engaging the rifling would be safe in 95-99.99% of rifled shotguns, but they have to account for the ones that aren't (same as why some companies download 7mm mauser). Doesn't really matter in the end, sounds like there's no concrete reason why it shouldn't be tried

 

[Longwalker]

I think that putting a gas check on a shotgun slug is a solution to a problem that doesn't exist.
A gas check would have to go on a solid bottom lead bullet, not a hollow base bullet. Such a bullet would too heavy for the pressures a shotgun barrel could handle. A typical shotgun slug already has a "gas check" - the plastic over powder cup.
A sabot is the answer to the problem of shooting a solid metal smaller diameter bullet in a shotgun bore.
There are rifles that can shoot a solid metal gas checked bullet of extremely large diameter - like the 600 Nitro express and a few extreme wildcats.
Try putting a non-hollow gas checked bullet in a rifled bore shotgun and firing it at even normal shotgun velocity of 1200-1800 fps and the shotgun would be blown to bits. It's not a mater of "liability" its a mater of common sense and unavoidable physics.

 

[tjhaile]

There are a bunch of full bore slugs out there.

Im sure someones madeit a gaschecked one by now.

https://www.ballisticproducts.com/mobile/Green-Slug-12ga-729-375gr-15_box/productinfo/7000005/

The hollow point doesn't strike me as a good idea; a wide flat nose would be better. Just like regular Foster slugs, it doesn't have much sectional density and the expansion will compromise penetration. A 12 gauge slug doesn't need to expand, it IS expanded!

The problem with shooting regular full-bore slugs out of rifled barrels isn't gas cutting; the wad should seal the barrel. The problem is that rifled barrels are designed to work with sabot slugs in terms of twist rate and depth of grooves.

 

[ted_dent]

A friend of mine cast and loaded the Lyman 525 gr. sabot slugs in his Remington 870 with an extended rifled choke tube. Typically got 100 yard groups that ran under 6". Obviously no leading because they are loaded into regular wads. I'm guessing most shotgun hunters would be happy with that accuracy and since he was casting & loading his own the price was far below commercially purchased ammo.

 

[stampede]

Longwaker has the answer. The pressures allowed are pretty low (11,500 psi). Gas checks may push the pressure way up.

 

[LUTNIT]

Hollow-based slugs give shuttle-#### stabilization out of smooth bores while keeping weight to a reasonable level to allow for a useful velocity for hunting. A solid slug would be closer to 2oz instead of 1oz so when fired at the maximum safe pressure it would have a nearly useless velocity; you could probably throw the slug as fast. Also rifled barrels are much more expensive to produce so would defeat the purpose of an inexpensive shotgun being the "every mans gun" for frontiersmen and settlers. There was early use of solid round-ball slugs in smoothbores but they were only effect at extreme close range due to the lack of rifling. The foster slug design solved this issue and made slugs useful out of smoothbores.

Sabots are used to shoot lighter slugs to reach higher velocities for better effect on game as well as better ballistics. You get more kinetic energy from the same maximum chamber pressure due to energy increasing much more with increased velocity than mass as well as less drop.