20 gauge AS-Grizzly fullbore , rifled choke. First try.

[Petander]

I loaded ten rounds like this:



Brush wad,cork,slug:



Velocity was as expected. Target at 50 meters for starters. Enlarge so you can see it.



Group size was about two feet, slugs were keyholing perfectly:




I had similar results with Svarog Zveroboy tailwad fullbore slug the other day. I tried it with IC as well, no good. They say it is for smoothbore. Oh well.

I guess these Grizzlys really are for a fully rifled barrel. Ideas?

[longbow]

What are slug and groove diameters?

It seems that at least some of the 12 ga. Russian slugs cast at about 0.728" and choke tubes tend to be 0.730" groove so with shallow rufling, not a lot to grip rifling. Not sure if 20 ga. is the same.

Can you set up water jugs or similar to capture slugs? If you can recover a few slugs without destroying them you'll be able to see if the rifling on the slug is good or skipped.

Are these slugs soft lead or harder alloy? If soft lead you could cast some from wheelweights or hard alloy and oven heat treat ir even just water drop as casting will help, then try those. If they do better that is an indication the soft slugs are skidding or stripping.

Deep snow is great for catching slugs but... you generally have to wait until spring to find the slugs.

Is there any leading in the choke tube? With powder coating even if the slugs are skipping rifling I'm not sure if you'd get leading or not... then there's that long wad column following to push any loose lead out if there is any.

Recovering slugs to look at is probably the best bet.

Shooting into a box of ground rubber or even sand might work.

Longbow

[centershot]

Petander, try a rifled choke tube. I used one in my 870 and it worked great!

[Petander]

Hard alloy,very tight fit - Carlson's tapers down quite a bit. No way to push through by hand.

[longbow]

Well, that answer's that part.

I'd still be looking to recover some slugs to look at. If rifling is distorted or stripped that tells you what's happening. If rifling is good then something else is wrong.

Might be worth trying a plastic gas seal then all card wad column to eliminate the cushion leg. If the cushion leg or gas seal is failing that could also be the problem.

Did you recover and cushion legs?

I've had gas seals fail on more than one cushion leg due, I think, to distortion during cushion leg crushing. Slug loads seem to be harder on cushion legs/gas seals than trap loads. Especially high velocity slug loads.

Longbow

[Petander]

Nothing recovered.

Yep,I'll see what all I have in all those cardboard boxes. I do have a different brush wad,somewhere.

Getting that 12 RB shooting so good makes me dream about a rifled barrel here,too...

[longbow]

In my limited experience with rifled barrel the same load that worked best in smoothbore also shot well in 12 ga. rifled barrel and that was 0.735" RB with plastic gas seal and hard card wad column underneath then roll crimped. 36 to 38 gr. Blue Dot was my powder charge and that based on Precision Rifle's PileDriver data for 610 gr. full bore slug.

I had poor success using a cushion leg or gas seal, hard card then fiber wad under the ball in smoothbore. Didn't try those in the rifled gun.

Longbow

[Cap'n Morgan]

The slug is obviously rear-heavy without an attached wad. Try adding a screw-on wad - or, just for the fun of it, turn the slug upside down to shift the center of mass forward.
You could also try a slower load. If the keyholing stops, it could indicate the rifling being stripped.

BTW: Do you know the twist rate in the 20 gauge Carlson choke?

[Petander]

Captain, I have a similar style Svarog Zveroboy tailwad slug,too. No success yet. This AS Grizzly is supposed to shoot from a rifled barrel. Rifled choke...? I'm finding out.

I tried three more different wad colums. Same load.

Two of these made round holes @ 25 meters. The one with a gas seal/nitro card/two tall "cardwads" (what do you call those black,hard things?) keyholed big time.



This is the same (russian?) cushion as yesterday, I only substituted the cork with this black "whatdoyoucallit?" Got round holes and a group this way. The other ,(italian) cushion, worked with 28 and 20 corks.



A blizzard / storm is coming with a foot of snow now, I'm glad I got this test done before it hits.



I will try a slower powder (VV 3N37) next but first shoot these two 50 m.

I may dump this column, it's very hard to get that 28 gauge cork to stay in the cup. It keeps slipping back up and out. But you need it in there for support,in this case under a 20 gauge cork.



All in all,this is pretty crazy stuff. If / when you find working components, you run out of them and can't find them any more...

[centershot]

Petander, try a rifled choke tube. I used one in my 870 and it worked great!

Duh! OK, I'm blind, it's right there in the title! Sorry!

[fastdadio]

[QUOTE=Petander;5345241]
I may dump this column, it's very hard to get that 28 gauge cork to stay in the cup. It keeps slipping back up and out. But you need it in there for support,in this case under a 20 gauge cork.

This statement makes me think you may be using the wrong wads for the type of hulls being used. If the wads keep pushing/sliding back out, I suspect you're using a tapered hull that's causing this. Maybe try using a straight wall type of hull?

[farmbif]

might experiment with different wads or forget the wads and just use the harder stuff like waxed card wads or nitro cards
how do other slugs shoot through that choke tube? tighter pattern than 2'?

[Petander]

[QUOTE=fastdadio;5345376]

I may dump this column, it's very hard to get that 28 gauge cork to stay in the cup. It keeps slipping back up and out. But you need it in there for support,in this case under a 20 gauge cork.

This statement makes me think you may be using the wrong wads for the type of hulls being used. If the wads keep pushing/sliding back out, I suspect you're using a tapered hull that's causing this. Maybe try using a straight wall type of hull?

Yep that wad is definitely not designed to hold a 28 cork. I wonder if any is? See the pic ?



Component availability is really bad here and nobody ships from USA anymore so I'm forced to improvise with whatever I have gathered.

[Petander]

might experiment with different wads or forget the wads and just use the harder stuff like waxed card wads or nitro cards
how do other slugs shoot through that choke tube? tighter pattern than 2'?

I did just that above in this thread, no cushion wad. Keyholing. My two new wad loads are the first ones to print round holes.

Wad loaded round balls shoot "okay", 4-5" @ 75 m but that load is very mild, a re-built factory trap round. Rottweil brenneke factory shoots 3-4" @ 35 m.

[centershot]

Petander, a while back, in the "525" thread, Cap'n Morgan said that he'd usd drywall joint compound to fill the base of the 525 slug. Do you think that might workhere to replace the component that pops back out after seating?

[Petander]

Petander, a while back, in the "525" thread, Cap'n Morgan said that he'd usd drywall joint compound to fill the base of the 525 slug. Do you think that might workhere to replace the component that pops back out after seating?

Might work. Or a nitro card instead of the 28 cork.

But the simple pink slug column (on the right in the pic) made round holes too so I'll use that one for now. Must check 50 m now.

[fastdadio]

[QUOTE=Petander;5345469]

Yep that wad is definitely not designed to hold a 28 cork. I wonder if any is? See the pic ?
Component availability is really bad here and nobody ships from USA anymore so I'm forced to improvise with whatever I have gathered.

I see now. I misunderstood your post, thinking the wad was rising up in the hull. Maybe cut a taper on the cork to fit the inside profile of the cup, or fill the cup with caulk.

[6pt-sika]

Petander, a while back, in the "525" thread, Cap'n Morgan said that he'd usd drywall joint compound to fill the base of the 525 slug. Do you think that might workhere to replace the component that pops back out after seating?

Put a spot of hot glue then put the 28 gauge wad that just might do the trick .

[Petander]

Another way to get rid of the cup.




I made two new loads with the top plastic wad cups cut away. Pink with italian cushion and a hard card, antique with russian cushion and a cork.

I also switched to VV 3N37 for less pressure. These are almost one oz slugs, not 7/8 as I thought. Oops. 3N37 is s much more appropriate powder here, to get some velocity.




I can get various length gas seals for 12 gauge but for 20 there is none. Cutting the cups adds a random factor which is buggering me but well...

[longbow]

You could try filling the cups with hot melt glue. Not sure if the heat would distort them or not but if not that would give you a solid base and certainly wouldn't pop out! I'd fill then turn over on a piece of cold steel with oil or grease on it, or parchment paper maybe. That will give you a flat top and no sticking.

Caulk as mentioned might work but I found that slugs and other filled with caulk tended to take too long to dry/set up for my liking... you don't want a liquid core that could squirt goo under pressure! You could probably get away with simply dumping a scoop of COW or cornmeal into the hull on top of that cup so it is a bit overfilled then seat the slug on that. It will compress under firing some but works well for me under round balls. And now that I think about it paraffin wax poured into the cup to fill should work and is cheap and easy.

A simple tube jig to cut the cup off should work to get easy and even cup removal, at least easier than unguided knife or scissors.

That is a nice looking slug! It looks longer in proportion to diameter than the 12 ga. version. I like the 12 ga. version too. Still window shopping but getting closer to spending money.

Can you line up a bunch of water jugs to try to capture a slug? 3 or 4 should do it then a 5 gal. bucket full of rags to catch and contain the slug. You'd be able to look at rifling then. That will tell you if there is skidding/skipping happening.

Longbow