Mine's a 45 Colt only Bisley x 7.5".  Groove is .452", throats are .449"-.450".  This seems to be a feature of the Ruger 45 Colts of this vintage--about 4 years old.  Dunno if they've changed their procedures, but they seem to think this arrangement is well-nigh perfect.

That is about to get remedied, if I can figure out where to get a throat reamer for less than $70.00.  Brownell's can be right proud of the products they sell, and after discussing the operation with Buckshot, I don't think the Brownell's reamer with .448" pilot is required to get the throats right.  Just a straight, .4525" reamer would do nicely.  Stilwell's (the custom sizer die folks at www.sizingdie.com) will do the operation for 45.00, and you need only send the cylinder.  Basically, I need to get off my lazy aspirations and correct this sitch--and there are resources available to do it. 

It actually shoots all right with gas-checked #454490's, but is very random and poetic with 200 grain plain-base SWC's.  This may be why I've palavered around for 3+ years......it will shoot with SOMETHING poured at home.  Still, it isn't RIGHT.     

Looks like we might need ta buy a reamer n pass it around agin'...

Ifin' mine needs reamed also...I'd sure be up fer it....

Got mine back from Ruger a couple weeks ago after a rebuild. They replaced both cylenders. Havnt miked them but tried pushing a .454" boolit through. A snug fit but no problem pushing them through. Same with my Bisley but I dont know what vintage the Bisley is as I recently got it used.

BIC/BS

Fourarmed--Got it, and reply sent.

LAR--I've read some commentary that the mid-frame 45 Colts aren't capable of the usual Ruger-level load intensities, but should be restricted to 250 grainers at or under 1000 FPS.  The pics I've seen show an absolutely gorgeous revolver, though--and 250 grains at 900-1000 FPS isn't something I'd stand in front of, in any event.

Contrast the poetic nature of Ruger 45 throats with the dimensions in my Redhawk by 44 Magnum......throats are .430"-.4305", groove is .4295.  Boolits at .431" shoot VERY well. 

K...nother ?

What's the cylinder length overall?

Tryin' ta design a bullet fer it....maximizin' case capacity...ie biggest nose possible...that'll fit in the cylinder n not protrude..

The cylinder length on my Bisley is 1.710".  I caution that the Bisley cylinder differs from the conventional cylinders in being unfluted and scrollwork-finished.  I don't know if it varies in length.

In my revolver, that would equate to about .475" throat length.  Don't forget to subtract the rim thickness of the loaded cartridge's overall length while figuring this out. 

K...TY....So a nose of .460" length would werk in the Bisley with .015" of clearance...

But the Blackhawk cylinder might be different....

This could be a heck of a hunk a lead...

Some preliminary idea's...

From smallest 235Gr.

To 325Gr.

Ta Mastadon 350Gr.

This is gonna be a Blast....

Wonder ifin' Dan'll cut 1 a each in a 3 cav. XL er 2XL Aluminum block...

---

The cylinder length on my Bisley is 1.710". I caution that the Bisley cylinder differs from the conventional cylinders in being unfluted and scrollwork-finished. I don't know if it varies in length.In my revolver, that would equate to about .475" throat length. Don't forget to subtract the rim thickness of the loaded cartridge's overall length while figuring this out.

---

I have a BH 45 convertable and a Bisley 45 and I use the ACP cylender in both guns so I would say they are the same length.

BIC/BS

Gee Buddy,,,350gr is all ya want?  

Way back in the beginning of the board I had MM cut me a custom 2 cav 380gr 45 mold,,one cav each GC & PB. 

THREAD HERE  <----------<<<

I get distracted easy by new shiny guns and havent done much with it,I do believe Lar45 got a few to try though......

380!!!! Wow...

Thought 350'd be nuff fer my recoil tolerance...

Sure would like ta hear how it werked out tho....

Well the new BlackHawk's been on the UPS truck fer the last 2 day's n the gunsmith's been at coffee when the driver arrived both days dang it...

But the molds I got on ebay arrived Friday n so's I cast some up...

1's a Lyman #454424 and this un's a GC design mosta the one's I've seen er PB...cast out WW's with a bit a tin added sized .452 and GC'ed n lubed they go 270Grs...

Loaded em in new Win. cases over 18.0 n 18.5 Grs. a the old 2400 at 1.660"...

The other's a #454190 PB no crimp groove looks bout like the black powder original .45colt loads boolit...no toppunch fer this un' yet....it's stuck on the UPS truck too....

Well ifin' the gunsmith can be there when the UPS truck gets there...aughta be able ta test drive er tommorrow...

---

Well the new BlackHawk's been on the UPS truck fer the last 2 day's n the gunsmith's been at coffee when the driver arrived both days dang it...But the molds I got on ebay arrived Friday n so'sI cast some up...1's a Lyman #454424 and this un's a GC design mosta the one's I've seen er PB...cast out WW's with a bit a tin added sized .452 and GC'ed n lubed they go 270Grs...Loaded em in new Win. cases over 18.0 n 18.5 Grs. a the old 2400 at 1.660"...The other's a #454190 PB no crimp groove looks bout like the black powder original .45colt loads boolit...no toppunch fer this un' yet....it's stuck on the UPS truck too....Well

---

DoubleJK, if you don't mind my asking, what did you have to pay for this Ruger with two cylinders? One of those has been on my shopping list for a year but the only ones I've found are more than I can talk myself into.

That's my pair of 45's of the 4 5/8th's Blackhawk variety. One is the convertable version.  Wanna guess which one?   LOL

K...Doughnuts n a thermos a coffee....will head fer town n get em this mornin'...on my way ta park at the smith's door till new 45 shows up....

Then home fer a quick trip ta the pond range fer a test drive...

Got them 454190's sized n loaded over 9 n 9.5 n 10Gr. Unique...

Made a toppunch that werked purty good...just turned a pure flat one nothin' fancy but it werked...

Ran 400.00 even delivered...

Well the saga a gettin' it home continues....parked at the smith's n occupied him with some goodies till UPS brung it....

Now enter CBI....computer was down today...no background checks being processed.... = no gun goin' home....

However got ta handle er some n get some rough measurements....cylinders fer the 45acp er runnin' .474cyl n .449-.450 throats n the .45colts .4805cyl n the same .449-.450 on throats.....no measerment on bore yet...

looks like were all runnin' in the same canoe....ie small throats....however the brass ain't gonna be over expandin' n being over werked in sizin' as some a the older model's reported cyl's runnin' over .486"...

Got er home n test drove er..

Not bad at all....nothin' real solid yet as the wind was blowin' n light goin' fast...

But I have some 8" round swingers at the pond n restin' on the hood a my truck the factory 255Gr loads were right on the money at 50yds.... could hit it real regular...

also fired some at the 18 n 18.5 Grs. a 2400 with the Lyman #454424GC....nothin' wimpy bout those...

the factory loads barely moved them plates but them handloads had em swingin' purty good....found a couple in the soft dirt I fired ta the side fer lookin' at....will post pics later....bet they would make a dandy deer load as is....

The Results

This #454424 was cast outa WW's w/1% tin added air cooled loaded over 18.5Gr 2400 and fired into soft piled dirt at 75yds...the boolit on the left is an Ultamax 250Gr Factory load fired from same distance...sure didn't take alot a fiddlin' ta find a Deer load fer this un'...

............DoubleJK, if ya wanna try out a heavy slug in your new 45 Colt, see below:

The one on the right would be what you'd be interested in. Just get'chersef a Lee 358-340F SC mould for $14. Cast, Tumble lube and run it up through a Lee .451" size die and there ya go! I did a bit of preliminary loads in my Ruger Vaquero with it using some SR4759 and H4227 and it was really nicely accurate at 25 yards.

I was up to about 850 fps when I ran out of slugs. I wasn't seeing any pressure yet. I did get around to casting some more of'em up but haven't yet processed'em into useable 45 Colt dimensions yet.

Buckshot 

HeHe...is there any grooves left after sizin' er down???

Might just give er a go...got several 45-70 molds.....the gould HP looks interestin' too....

Let me know how yers werks out when ya get em shot agin'....

Got 475-480's MM 325KTGC yesterday n cast some up outa 160-1 WW's ta Tin...

475-480 you a dipper caster? Had ta open the sprue holes a tad ta get my bottom pour ta not shoot back at me....but once I had a big nuff hole Dan's molds cast purty boolit's real easy...

Weighed 315Gr. naked n right at 324-325Gr. GC'ed n lubed...

Got em loaded over AA#9 from 14.5 to 16.4Gr's....at 1.720" L.O.A. and a heavy crimp...they are purty visible in the end a the cylinder....look real impressive...bet these er gonna jump a bit more n the 250-260's I've been playin with so far...

Got em test drove yesterday n they don't jump near a bad as I was figurin' on em doin'...

The 14.5 Gr. loads were runnin' down range at 845fps...n the 16.4Gr. loads whistled along at 1012fps...them faster one's must be carryin' some clout as the 8" steel swingin' plates I was shootin' at were swingin' bout 90degrees up at impact...factory 250's make it move but not far...

all signs point to purty mild pressures...recoil is not anything like my SBH in .44Mag pushin' 280Grainers at a bit higher speeds...cases drop out with no more effort than the factory mild loads...

Just to compare the apperant strength of the .45 BH to the .44 SBH I had along too..I took the cylinders n tried swappin' em.... surprised me the BH.45 will seat the SBH.44 but the SBH won't even let the .45 cylinder in the frame..it's longer than the SBH.44   

Hmmmm' thought it would be the other way around....

Has anybody played with these over normal weight boolits in the BH.45 n what kind of velocities were ya able ta achieve...

Deputy Al...saw where ya's got yer throats reamed...would sure like a before n after report when ya's try er out....