Diabolo Slugs in Smoothbore

[DanLee]

Is a rifled barrel necessary to stabilize the slugs that resemble an air rifle pellet? I acquired a mold that casts such slugs. The slug has a hollow base.

[Outpost75]

Less accurate than roundball in my .410


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[longbow]

I have read posts going both ways on that one. Some people claim they shoot well from smoothbore and some claim they don't.

They are a weight forward/nose heavy design so should shoot reasonably well to at least 50 yards if fit to bore is good... at least for cylinder bore.

If your barrel has a tight choke maybe not.

Try a slug in your trap wads and push through the barrel. The slug/wad should push through with about 5 to 10 lb. push.

If too tight then try a wad with thinner petals. If too loose try a wad with thicker petals.

There's lots of load data for those slugs and a thread dedicated to them here.

Also, if you are shooting them through a tight choke they should be cast from soft lead.

And... while I don't have personal experience with this slug I can say from experience shooting several other HB designs that you should either fill the hollow cavity with caulk, hot melt glue or similar or use a 16 or 20 ga. nitro card wad in the bottom of the shotcup or the wad may jam into the hollow cavity.

The shorter story is that with correct load data it certainly won't hurt to try!

Longbow

[W.R.Buchanan]

As Longbow has stated, some get good results from Smooth Bores with the Lyman 525 Slug and it depends alot on how they are loaded.

<50 yards they are generally exhibit decent accuracy, and if you are under 3" at 50 you are doing good.

Some have gotten excellent results out to 100 yards from Fully Rifled Barrels with Scopes attached.

There is a lot of subjectivity here on this subject and you really have to try and find what works for you. Lots of Load Data available in the Lyman Shotshell Manual and from BPI so that's where to start.

Randy

[DanLee]

Well, loaded up five shells with a recipe for Fiocchi hulls and Green Dot for 7/8 oz shot from Lyman's 5th Edition. The slug weighs 365 grains, so less than 7/8 oz. Used 28-gauge fiber wads in the shot cup to build up the column. Roll crimped to lock it all in. At the range the slugs hit face on at 25 yards and a couple inches high from the Remington factory slugs I used for a control. Accuracy was very good with the first three shots in one ragged hole. Recoil was a lot less with my load. Will load up another 10 and try again tomorrow at 50 yards.

The gun is a 16-gauge Remington 1100 with a smoothbore slug barrel and rifle sights.

[megasupermagnum]

That really depends on a lot of things. The Lyman 525 can be stabile from a smooth bore, exceptionally so. I've heard more than few people trying the 20 gauge version, and can barely get them to shoot with a rifled barrel.

So a "air rifle pellet" style slug can be accurate from a smooth bore, yes. That said, small changes apparently make big differences. I've only ever heard of good results with the Lyman 525, meant for 12 gauge.

[DanLee]

This is a Russian mold, a Svarog brand made for the 16 gauge and meant to be used with a plastic wad column. It measures .595" at the skirt and .610" at the head. I will find out more about its accuracy at 50 yards.

[megasupermagnum]

That's where I can't help. If it is exactly scaled down from the Lyman 525, it could fly great. If not, who knows. Overall with any slug that goes in a lead shot wad, I've always found the wads are too variable for great accuracy. They can be good, but not great. There are very rare exceptions, but I believe I've only seen it in rifled barrels. Note I am differentiating "flying stabile" from actual accuracy.

[longbow]

Again, no personal experience with the Lyman 20 ga. sabot slug but what I've seen posted isn't complimentary when shot from smoothbores. No idea why Lyman changed proportions rather than just scaling down but so they did.

Lee doesn't produce a 20 ga. Drive Key slug because they said they couldn't get acceptable accuracy.

If scaled down why not?

It makes one wonder!

Part of the black magic of slug loading and shooting?

Are the 20 ga. Russian copies of Lyman sabot slugs the same as Lyman or scaled from the 12 ga. version... or?

Longbow

[DanLee]

Here is a photo of the slug and components as well as a couple loaded shells. I also put together some round ball loads.

[megasupermagnum]

I think part of the reason in 20 gauge is that people like to load that gauge hot. A 12 gauge Lyman 525 scaled down to 20 gauge would be a lot lighter, maybe less than 5/8 oz, although that's a typical factory 20 gauge slug. The Lee 7/8 oz scaled down would be even lighter, and a 1/2 oz 20 gauge slug might not be desirable, although I'd try it.

[longbow]

From the pic that looks like a scaled down version of the 525 gr. not the longer Lyman 20 ga. design... hard to tell for sure but it looks to be about the same proportions as the 12 ga. slug.

How well does that slug fit your bore? A standard 20 ga. is 0.615" so at 0.595"/0.610" it is a rattle fit to bore. A wrap of Mylar or Teflon might work to make for snug fit. If not snug accuracy will be poor.
Is the barrel choked?

I'm guessing you cut the petals off the wad? If not the slug wad petal combination will be much oversize and petals will shear.

Longbow

[W.R.Buchanan]

Some of the things that have worked for these slugs in 12 ga. might translate to 16 ga.

Filling the Base with Hot Glue, and seating the slug on top of a .070 card wad.

Just to get some theory out of the way. in order to achieve acceptable accuracy IE: going in the same direction more than once. These slugs must be launched perfectly square to the bore everytime. If they are cocked to any degree they will fly stupid.

You will note that in most cases boolits coming out of rifles are pretty close to perfectly in line with the center line of the barrel and they are spinning. These slugs shoot much better from a Rifled Barrel simply because they are spinning around centerline. They still have to be introduced into the rifling as square as possible to mitigate as much of the alignment error as possible. This is the reason for filling the bases with hot glue, and sitting the slug on top of a hard card. It prevents the wad from getting shoved into the rear of the slug leading to Misalignment with the bore.

From a Smooth bore they aren't Spinning, so in order to fly strait they must be launched so the Front Face is Square to the direction of travel. That is impossible to duplicate every time. There will always be some degree of misalignment. The severity of that misalignment will define how far from the POA the slug actually ends up. The distance of the shot will also Amplify the POI. That is why we say <50 yards from a smoothbore.

For Hunting of Deer and Black Bears in the US these slugs can be as devastating as anything out there. That big flat nose dumps its energy very quickly after first contact , adn that is why it ws designed that way in the first place. Plus that,,, they look cool!

Randy

[DanLee]

Results at 50 yards. I attached a Merit aperture sight to my shooting glasses for this test. I'm satisfied with the accuracy of these slugs in my 16-gauge 1100. I used the first three shots to zero in.

[megasupermagnum]

Ummm... You aren't going to hunt with that, are you?

[DanLee]

Why not? The slugs seem to be hitting the point of aim.

[W.R.Buchanan]

5 shots into a 1 foot group is not suitable for even shooting at Cans. You need a little more work on that load!

OK,, after enlarging your picture it appears that your shots are going into the intended POI as long as you were shooting at those other diamonds,,, but you need to shoot some groups to see how consistent the shots will be.

This is what you are looking for.

Randy.

[DanLee]

Yes, I thought it would be obvious that the corner diamonds were what I was aiming at for the last three shots. The barrel has open sights and my eyes are in their seventh decade of use, hence the addition of the aperture on my shooting glasses. This was strictly an exercise to determine if the diabolo slug would shoot accurately through a smoothbore. I'm satisfied that it will, at least to 50 yards with open sights.

[longbow]

Weeellll... maybe not so obvious to some. I was going to make the same observation as Randy that a roughly 12" group at 50 yards is nothing to be proud of but I also didn't pick up on the fact that shots #2 & #3 are pretty close then #4, #5 and #6 are all on or very near the corner diamonds. However, I can be a bit slow on the pick up (some might say quite slow! I blame it on a misspent youth!).

So, considering that the target isn't a group as such that's pretty darned good! Some of the holes are slightly oval so slugs were not fully stable but out to 50 yards that accuracy is plenty good.

I do agree with Randy though that you should shoot some groups and check for repeatability. If you find oval holes are common there is some instability or bad launch that you may be able to address by sorting out fit to bore. That may also shrink group size and eliminate fliers.

Looks like you are off to a pretty good start though.

Longbow

[megasupermagnum]

Ok, so if you shot three shots (one at each diamond), that doesn't look bad at all. I don't like that #4 was the only shot that appears to have hit square on, the rest appear to be wobbling. Try filling the hollow base with hot glue. That helped mine out a lot.