Choke for Slug?

[Super Sneaky Steve]

Hey guys, I cast up some 0.690 round ball and I intend to not use a shot cup. Instead I'll be using a doughnut wad to keep it centered.

I've always used cylinder chokes for slugs in the past, but just for fun I tried passing it through my chokes and I was surprised. It rolled through the IC and even got by the Modified without having to be pushed through. The full choke won't let it pass but I'm sure it wouldn't take a lot of force to get the pure lead though.

So I know there's rarely a stead fast rule but what choke would give the best accuracy?

[megasupermagnum]

To be honest, I don't think you will get acceptable accuracy with a .690" ball without a shotcup, no matter the choke. It sounds like full might stand the best chance in your case. Even then, a full choke on a 12 gauge usually has an ID of .700"-.690". It would barely be touching the ball at all. Try it and see, but I would load some with the shotcup too.

[Super Sneaky Steve]

Thanks for the advise. I don't have shotcup wads with thin pedals so I was trying to do without. I'd also like to use biodegradable materials if possible.

I don't expect much in terms of accuracy, but if I could take a deer at 50 yards or less I'd be happy.

[megasupermagnum]

Maybe 25 yards, I just do not see you getting even paper plate accuracy past that. Since you presumably have the mold already, give it a try anyway. If you want a paper wad only load that is accurate to 50-60 yards, try a .735" ball. Recoil is surprisingly light with lower velocity loads.

[6pt-sika]

Since I don’t load any slugs for the screw in choke gun I’ve got that’s a moot point . Most of my slug guns are SxS’s and over half are damascus or twist . Everything I load is set up on the apprenension that it’s going thru a full choke . Some of my slugs fit well in a normal shot cup and others get a mylar wrap with the petals trimmed off and I’ve had no problems . My slug loads meet my parameters which is usually a good three shot group out of one barrel at 25 yards and buckshot in the other barrel . Like I said my stuff meets my parameters so that’s all that matters as far as I’m concerned .

[bikerbeans]

I was going to post my thoughts but considering how bad my 20ga round ball loads have been performing I think I will be quite.

BB

[toallmy]

Well if all else fails patch the ball to fit the bore . It Can't hurt

[centershot]

Well if all else fails patch the ball to fit the bore . It Can't hurt

This actually works pretty well!

[missionary5155]

Good morning
Years back we decided to use a Fox B 12 gauge for an inexpensive double rifle.
So began equalizing both barrel chokes little by little to find what constriction gave the best accuracy from that particular Fox B barrel.
Found that using a .685 RB cast with range scrap or WW air cooled in a standard Winchester field load with the shot dumped started giving better accuracy at .007 constriction and the best attainable with those barrels. The same Winchester load best accuracy happened at .005 and continued at .003 choke where I stopped reaming.
Your barrel an easily be a bit different. Powder charge, wad, lead mix ….. any variation will cause differences. But over the years I have learned you must measure the real constriction. and an OK guide for me is .007 to .003 is about the best.
Screw in chokes really make a lot of sense as the cost is far less if you want to experiment reaming your barrel.
Mike in LLama Land
Again

[Super Sneaky Steve]

I took some measurements today. Results were very interesting. I'm using two O/U shotguns. The longer has screw in chokes, the short "tactical" doesn't.

The one without chokes was 0.720" and the screw in cylinder choke was also 0.720" I tried hammering the slug though the barrel and there was a little tight spot further down. These are cheap imports but I like them. What surprised me was after I slugged the 0.720 ball it fell right through my rifled choke. The rifled choke takes a 0.735 ball to fill the groves.

The gun without chokes was 0.720 all the way though, the one with screw in chokes was .730 in the barrel but like I said, the cylinder choke brings it back down to 0.720. Seems like a 0.735 would be perfect with the rifled choke.

I made my slug by hammering one of my .690 balls to get a slightly oversized fit.