figured out why my rossi circuit judge is not accurate...

[hipoint]

Finally broke out the calipers and did some measuring this evening.... the .45 colt ammo that I have measures .444 inch where it meets the case. The barrel on the circuit judge measures .456 inch... that's a pretty large gap, and no wonder my bullets are flying crazy...

so does anyone have a suggestion as to a projectile from a .45 colt that would expand in the barrel slightly? anyone who actually OWNS a .454 casull care to put some calipers on the projectile and measure for me? I'm thinking if I can't find a .45 colt round that will slightly expand, then I might be ok to load my own .454 casull rounds (weak of course), that is if they are closer to my barrel size.

anyone care to weigh in here with some real world information?

 

[NOLAEMT]

are you saying the diameter of the 45 colt bullets is only .444? It should be .452 in any 45 colt bullets i have ever seen.

The diameter of your barrel should be .451, groove to groove, as well. Are you shure your calipers are working correctly?

and no, I don't know of any ammo for 45 colt that would expand when you shoot them, other than hollow base wadcutters, and they will not expand to the size you need.

 

[hipoint]

even if my calipers are not spot on accurate, they would still show the difference between the two.

so my calipers are measuring the round as .444 where it meets the case, but that may or may not be accurate as I do not have a super expensive set of calipers. But the difference is there regardless of if I used a nasa set or mine...

maybe I'll try to put the calipers on some ammo at the store tomorrow, the ones I was measuring were hornady leverevolution 225gr.

Is the .454 casull only 2 hundredths larger than a .45 colt? or is it slightly more?


edit*** also I can put the .45 colt ammo inside the end of the barrel, only the case stops it from falling all the way in....

 

[jakk280rem]

Is the .454 casull only 2 hundredths larger than a .45 colt? or is it slightly more?

same size. .451 jacketed diameter, .452-453 cast diameter. to get an accurate measurement of your bullet diameter, you'll need to pull a bullet and measure it at the base, not behind the ogive.

also, while youv'e got the calipers fired up measure the forcing cone and chamber mouths.

 

[hipoint]

sorry, I meant to say thousandths...

 

[hipoint]

what kind of ammo?

it's in my second post, it's hornady leverevolution 225gr

 

[jakk280rem]

yeah, you posted as i was typing, i edited it.

 

[hipoint]

right now this thing is operating like an old blunderbuss... I'm calling rossi in the morning!

I'm suspecting that this is the way the barrel is supposed to be, I would be surprised if a barrel was that far out of spec. Since I'm having a hard time unloading this critter (i'm being too honest with the buyers) I figure I'll see if I can't make some ammo work for it...

 

[hipoint]

I don't know what a forcing cone is... I'm guessing that's at the end of the cylinder? and the chamber mouth is at the rear of the cylinder? or is the chamber mouth at the rear of the barrel?

the rear of the barrel was significantly larger than the crown of the barrel (.466), the far ends of the cylinders are.... .454

 

[hipoint]

every other gun that I own, when you put a bullet tip into the crown of the barrel it won't go in anywhere near the casing... this one goes all the way to the casing, and I think would fall right through if I removed one... I don't have any tools in the house or I'd yank one out right now to see, I'll get in the shop when I can tomorrow and yank one.

 

[LoonWulf]

Interesting. The forcing cone, is the funnel shape at the back of the barrel. I dont know what specs they should hold. Getting good solid measurements of the forcing cone, and chamber throats, should help you on your way to finding a good load. Might want to slug your bore also

 

[bigedp51]

hipoint

Your bullets will be larger in diameter behind the crimping groove or inside the case, they should be .451.

The 170 grain Hornady 30-30 rifle bullets below are made the same way.



.308 below the crimping groove.



.299 above the crimping groove.



Sierra makes the bullet .001 smaller or .307 and .306 in front of the crimping groove, its one way of keeping chamber pressure down on older firearms and keeping things in one piece.







This is "WHY" the bullet test for muzzle wear is meaningless unless you know the bullet diameter in front of the crimping groove.

On top of this the the cylinder bores are choked to prevent chambering of rounds larger in diameter than the .410 shotshell and longer than the .45 Colt on the Judge. Your problem might be the cylinder size "choked" diameter and forcing cone diameter. ("forcing cone"- the flared opening at the rear of the barrel where the bullet first enters the barrel)

The Judge also has shallow rifling to get better grouping from the shotshell loadings and accuracy suffers with the .45 Colt ammo.

http://www.americanrifleman.org/ArticlePage.aspx?id=1526

"The bottom line is that, while Taurus revolvers in general have earned a reputation for mediocre accuracy, these .45/.410 revolvers have dramatically lowered the bar. One author, writing for a respected gun magazine, praised the Judge to the skies (naturally, since print magazines never publish an unfavorable review of an advertiser's product), but admitted that it would barely keep its bullets on a humanoid silhouette target at 25 yards! Considering that practically any Colt or Ruger .45 LC revolver will average 2-3" groups at that range with factory loaded ammo and no tuning whatsoever, the Judge's accuracy as a .45 LC revolver is simply unacceptable."

http://www.chuckhawks.com/taurus_judge.htm

 

[hipoint]

one would still think that with an 18 inch barrel that it would hold better patterns than it is. I will try to get some different measurements today on some other ammo.

I think it's possible to get this thing a little more accurate than it is by using a slightly larger diameter round, I will pull out a bullet when I get back from work and see how hard it is to force through the barrel, my guess is it will just drop straight through...

 

[jakk280rem]

going to a cast or lead 45 colt bullet will let you pick up a thou or two in diameter. also, try a heavier bullet. that light jacketed hornady you are using might not be playing well with the shallow rifling. a softer bullet (than the jacketed types) will conform to the rifling easier.

 

[rcmodel]

I doubt it is going to matter a whole lot what size bullets you use.

A .45 Colt in a .410 chamber has a long ways to rattle around in the loose 2 1/2" .410 chamber before it even gets to the forcing cone.

I would guess your best bet would be Remington .45 Colt lead bullets if you can find them.
http://www.midwayusa.com/product/16...g-colt-455-diameter-250-grain-lead-round-nose

They are made from very soft lead with a hollow base designed to expand to fit the loose bores common in old six-guns.

Might help in your case.

rc

 

[hipoint]

I doubt it is going to matter a whole lot what size bullets you use.

A .45 Colt in a .410 chamber has a long ways to rattle around in the loose 2 1/2" .410 chamber before it even gets to the forcing cone.

I would guess your best bet would be Remington .45 Colt lead bullets if you can find them.
http://www.midwayusa.com/product/16...g-colt-455-diameter-250-grain-lead-round-nose

They are made from very soft lead with a hollow base designed to expand to fit the loose bores common in old six-guns.

Might help in your case.

rc

I understand this, but you would think with an 18 inch barrel that it would have time to stabilize... Provided it's actually touching the barrel

 

[rcmodel]

Well, if it hits the forcing cone going partially sideways, I don't think how long the barrel is would make much differance.

rc

 

[hipoint]

Well, if it hits the forcing cone going partially sideways, I don't think how long the barrel is would make much differance.

rc

ahh, I see. I really need to ride around some and put my calipers on some other bullets... today was a bust, I had to work all day (glad I have some work to pay the bills with though!)

 

[NOLAEMT]

Are you saying that the CASE will fit in the muzzle of the rifle?

If that is the case, you need to send it back to taurus/rossi and have it rebarreled. that is unaccecptable. Like someone else said, a loaded round should only go in the muzzle a little bit, not anywhere near down to the case mouth.

If the bore is that oversize, no bullet you are going to find will give you any accuracy.

On another hand, from other people I have talked to, the circut judge seems to be about a 4" gun at 50 yards. Hardly better for anything that casual can plinking.

 

[hipoint]

I can do about 1 inch grouping at 25 yards, no problem... that's what's weird as heck... it seemed great, then went for some longer range stuff and WOW did it start opening up...

and yes, the bullet will fit down to the case, the case won't go in, but if I hit it it probably would. everything else I have stops about 1/8th inch before the case hits the crown.

 

[NOLAEMT]

Thats probably a result of the bullet failing to stabalize, you will get ok groups at short ranges, as the bullet it still stabilized somewhat, and as you go further, it goes rapidly down hill...

and I re read my post, I meant 4" at 50 yards, not 25. sorry for the misprint.

 

[rcmodel]

You might have to accept the fact that it is what it is.

It's a shotgun that can also fire bulleted cartridges.
Not a rifle that can also fire .410 shotgun shells!

A revolving .410 shotgun just cannot group .45 Colt bullets like a dedicated .45 Colt chambered rifle might.

Bigger bullets that will still fit in the chambers is not going to fix that inch long jump out of the 2 1/2" .410 chamber and into the .452" cylinder throat.
Because it doesn't have cylinder throats.

rc

 

[451 Detonics]

I would consider getting some brass 410 hulls, some .457 Buffalo Bullets and some Trail Boss powder and work up a load.

 

[Badlander]

I would trade it for something that shoots well or hang it on the wall!

 

[BCRider]

Well, unless Hornady screwed up a batch of ammo and put .444Marlin bullets into .45Colt brass I'd say that you need to go back and read or re-read bigedp51's post about how some bullets are smaller on the exposed portion but still right for the part that's in the case. If this is common then you can measure factory ammo all you want and will just become even more confused. What you REALLY need is a bullet puller and then measure the portion of the bullet that is inside the casing. Until you pull the bullets so you can perform an honest measurement you're just shooting in the dark.