Smoothbore help

[P.W.Berkuta]

I need some help with selecting a starting ball dia. and patch thickness for a .62 cal Colerain  barrel. Hey - what the heck - how about starting loads - this will be for target use for now.

[roundball]

Have you / can you mic the bore accurately?

[Randy Hedden]

The first thing you will have to find out is whether the barrel is .62 caliber or if it is a true 20 gauge bore which is smaller than .62 caliber by about .005". If you don't have a set of calipers or other way to check the bore, maybe someone has a 20 gauge from Colrain who can help with the measurement.

In my three 20 gauge barrels I use 75 grains of 2ffg, a .015 thick patch and a .595" ball for round balls, but none of my barrels are Colrain barrels.

Randy Hedden

www.harddogrifles.com

[P.W.Berkuta]

Well, taking 6 measurements at six different locations around the muzzle with a snap gauge I get an average of 0.609".

[Daryl]

PW- the usually preferred size is .020" to .030" under bore size for the round balls. I know the guys here use .595" in their 20's with a .020" to .022" denim patch.  Easy loading and good accuracy no wiping. I think some have difficulty with their smoothbores shotoing 'dirty' due to using too thin a patch that doess't clean well as you load the next one, nor hold much lube.

[P.W.Berkuta]

OK, so far here is what I came up with;  I found some 0.570" Hornady swaged balls and I got some heavy canvas duck cotton cloth which measures 0.020" compressed. I greased up the patch with my "super duper" patch lube. I then thumb started the ball/patch combo into the bore - it went in a bit more than half. I then finished her off with the ram rod and sent her home. Went down with a slight resistance but smooth and steady. I then got my CO2 ball discharger and "shot" the ball at my couch - it did hit with a firm "thud". The patch/ball combo looked good and showed some small cloth imprint on the ball surface. I will give this a try on Sunday at the range. I think I try 60 gr of 3F to start --- 

[T*O*F]

I found some 0.570" Hornady swaged balls and I got some heavy canvas duck cotton cloth which measures 0.020" compressed.

Paul,
I shoot .570's with a .017 ticking patch in my .58 smoothbore.  It will thumb start too.  You can probably go up to a .600 ball in your 20 ga.  Also try some 2F, you might find it works well and is more pleasant to shoot.  I shoot both in mine but find that the 2F makes fouling a bit more manageable.  It burns slower and spreads the fouling up the barrel, while the 3F is more rapid and stays toward the bottom of the barrel, often accompanied by that dreaded hard fouling ring.

[roundball]

Well, taking 6 measurements at six different locations around the muzzle with a snap gauge I get an average of 0.609".

That's why I asked...it sounds like my GM .62cal which is .610", and I used:

80grns Goex 3F
.015" lubed patch
.600" cast ball

[P.W.Berkuta]

Thanks all, I give er a try tomorrow -- all good info  - Paul.

[Leatherbelly]

 I would like to add this. Not all .62's are as they say.Mine( a Longhammock) is said to be a .62 but after carefull measuring,it's a .617 or .618. No prob,I shoot a .595 with a good .024 denim patch. Being a 46" barrel,I precut my patches a tad larger to carry more lube. No wiping of course.

[James Rogers]

Just because a gun is supposed to be cyl. bore do you guys just mic the muzzle or do you use a bore mic in the barrel to get an exact measurement?

I know on most original English fowlers, the muzzle was flared wider than the bore size.

Are any barrels being made with flaring muzzles that got 2-4 bore sizes larger?

[Daryl]

There were also guns made with barrels tight in the middle, flaring to the breech and flaring to the muzzle.  The gun makers 'found' they shot harder - HA!

[David Rase]

PW- the usually preferred size is .020" to .030" under bore size for the round balls.  Easy loading and good accuracy no wiping. I think some have difficulty with their smoothbores shotoing 'dirty' due to using too thin a patch that doess't clean well as you load the next one, nor hold much lube.

Daryl, or anyone else,  My soon to be 16 gauge Tulle has a bore of .656".  NEI sells .630 and .635 molds.  Which mold would you go with?
DMR 

[Daryl]

David - I'd go with the .630 mould.  It will allow for a thicker patch than the .635" mould and will hold more lube, which makes loading easier.

[David Rase]

Daryl, Thanks for the reply.  .630 is what I was leaning towards based on a couple of 20 gauge smooth bores I owned in the past.  One I could not hit the broad side of a barn even if I was on the inside until I switched from .600 to .590.  I made that discovery while I was selling the gun.  I had no .600's so I grabbed a handful of .590's so the customer could fire a couple of test rounds.  The gun shot so well with the smaller balls and thicker patchs that I had second thoughts about selling the gun.   Thanks once again for your input.
DMR

[Daryl]

Always a pleasure David. As you know, I prefer the larger sizes of balls in rifles - preferrably only .005" under as .010" under show poorer accuracy in general. It doesn't show at 25 yards, but further out, the difference is there. Nit-picking perhaps, but it's there.  Taylor's 1728 Bess does a good job with .740's (Tanner Mould) with very heavy patches.  The larger the smoothbore, the smaller the balls can be.  This is especially true when using WW alloys for the balls.

 Can anyone guess what a 25 pound powder box full of WW .595's would weigh?  How many balls that size will fit in the box?  Hatchet Jack has filled one, ready for a year's shooting - maybe more.  His rifle, which sees much less shooting than his smoothbores, has over 7,500 rounds through it - in only about 3 or 4 years shooting.

[mdtnhunter]

I usually use .595 with a pillow ticking patch with good results.