Recent Ruger Blackhawk throat and bore specs?

[Abert Rim]

Are they running close to optimum lately? Have a new .45 Colt Bisley incoming and wonder what to expect -- and hope to hell it is not undersize throats and a choked barrel where it screws into the receiver, as of old.

[DougGuy]

It's really anybody's guess until you get it in your hands. I check for thread choke by patching a plastic cleaning jag tightly into the bore with a couple layers of paper towel, push it towards the frame and observe any change in resistance to keep it moving. If it slides out the forcing cone without any noticeable difference? YAY you have no choke! If it slows just a bit then goes on through you may have a tiny choke, if it stops and you have to beat the cleaning rod to get it through, that's severe choke.

I'm assuming it's a medium frame model with 3 digit prefix in the serial number. Throats on those often run in the .4505" neighborhood. Push a dead soft lead slug not a boolit through the bore, now see if it will go into any of the throats.

Doug

[Abert Rim]

Thanks Doug. It appears Ruger just made a small run of stainless Bisleys in .45 Colt/.45 ACP, as the usual suspects -- Bud's, Grabagun, Kygunco -- have them in stock and there are several on Gunbroker.

[Hickok]

My recently bought Blackhawk 45 Colt needed cylinder throats reamed, as they were too tight. (just as Doug stated.)

Mine are now .4525".

[6.5X284ever]

The glut of Stainless 45 Colt Bisley convertibles, that popped up on Gunbroker overnight recently, were an RSR Group (distributor) exclusive. I had been watching their site for a while and they got a shipment of probably about 100 recently. I picked up one for myself from RSR a few weeks ago when they first popped up. FWIW I will tell you what I can about mine: Cylinder gap is .006 . Trigger pull weight is OK, but significant take-up or creep, almost like a 2-stage trigger. Cylinder throats- I tried dropping a Hornady XTP .452 from rear to front. Went through some cylinders with only a light push from the rear using a brass punch and the palm of my hand. Others required some "grunt" to the point where it was uncomfortable/painful pushing with my palm against the punch. They all went thru without tapping with hammer or other instrument, but some tighter than others. Not very scientific, but I would say the throats are pretty inconsistent, but perhaps not too undersized ? I pushed a .45 jag with double patch, and am not appreciating any obvious thread choke. I haven't shot it yet, but unless the accuracy surprises me, the cylinders will be sent for honing/uniforming.

[Abert Rim]

I'd bet that's the batch mine came from. I will report once I have it in hand. Glad to hear you didn't perceive any barrel choke.
Were the throats on the .45 Colt cylinder similar to the throats on the .45 ACP cylinder? This will be my first convertible in 50 years of Blackhawk shooting.

[6.5X284ever]

TBH haven't fooled with the ACP yet.

[Ed K]

Are they running close to optimum lately? Have a new .45 Colt Bisley incoming and wonder what to expect -- and hope to hell it is not undersize throats and a choked barrel where it screws into the receiver, as of old.

“As of old” would be oversized chambers & throats and without evidence of thread choke.

[6.5X284ever]

326415Good news and bad. Shot the 45 Colt today for the first time. First 5 shot group at 25 yards was about 1.5" or 2" rested, which was great. Bad news- sights maxed out to the right to get it zeroed. Back to Ruger it goes after I shoot it a little more. Ammo was Missouri 255 Keith HT coated, 10gr Unique. AV 1043 ES 19. SD 7.3

[Abert Rim]

Sorry to hear about the sights, 6.5. Ruger's inconsistent QC is baffling -- and yet I keep buying the damned things.
You know what they say about insanity:
‘Insanity is doing the same thing over and over again and expecting different results.’ ;-)

[Hickok]

6.5x284, we all know it's a bummer when this happens, but Ruger has excellent customer service....just wish we didn't have to use it so often.

I have a "fix" that I have used for this windage problem. I order a new Ruger rear sight blade, (same height as original)but with a more narrow sight notch....they make several different widths, and then file the notch on the right side until I get a good zero. Usually, you can get the sight more centered than having cranked all the way to right.

About .007" of windage, depending on barrel length, will give you about an inch impact movement @ 25 yards. Give or take....!

[DougGuy]

About .007" of windage, depending on barrel length, will give you about an inch impact movement @ 25 yards. Give or take....!

I tried to search for the thread pitch of the windage adjustment screw LOL NOBODY wants you to know what thread it is! If you knew that you could then figure out how much the blade would move with 1/4 turn of the windage screw.

It's not a real fine thread, and it IS a right handed thread on the rear sight windage screw.

Back to Recent Ruger Blackhawk throat and bore specs?

[kingstrider]

I recently picked up a 5.5" Bisley Blackhawk Convertible chambered in 45 Colt and 45 ACP. I have probably owned a dozen Rugers in 45 Colt and every one of them had undersized throats. This one measures .451” using a minus pin gauge but my .451” reamer pilot will not fit. The 45 ACP cylinder is also undersized and neither will accept a factory .452" bullet which is not good. I will shoot the gun before and after mods but already know that reaming the cylinders will improve accuracy.

[Abert Rim]

Well, I should know sometime next week. Hope it comes out fo the box "right," but that's not often the case with Ruger.

[DougGuy]

I recently picked up a 5.5" Bisley Blackhawk Convertible chambered in 45 Colt and 45 ACP. I have probably owned a dozen Rugers in 45 Colt and every one of them had undersized throats. This one measures .451” using a minus pin gauge but my .451” reamer pilot will not fit. The 45 ACP cylinder is also undersized and neither will accept a factory .452" bullet which is not good. I will shoot the gun before and after mods but already know that reaming the cylinders will improve accuracy.

I gave up using piloted reamers years ago. A 32 cylinder came to me with throats that would take a .310" pin only partways in the throats as they funneled downward in diameter until a .309" pin would barely squeak through some of the throats. Using a piloted reamer on a cylinder like this the pilot would have to be small enough to clear the megaphone and once it reamed past that part, you would have to use a larger pilot or just wing it with no support on the pilot. The Sunnen hone allows for overcoming obstacles that piloted reamers cannot overcome and turn out a round, parallel throat despite the egged or funneled factory throats.