Ruger blackhawk 44 special chamber mouths

[seabreeze133]

I had a Ruger Blackhawk 44 special for awhile and never could get it to shoot good groups so it went away.

Finally discovered why. My 2 cavity Lyman mold drops bullets with 2 different size boolits...as much as .003 difference. Plus the revolver chamber mouths varied enough to make a difference.

So....has the current crop of 44 special QC improved as far as consistent chamber mouths? Plus I figured out which cavity to use.....all by myself. :o)

NEVER will I use one a caliper as I have a Starret mike and read the instructions.

Probably buy another Blackhawk 44 special, but will take my bullets to check chamber mouths.

thanks

seabreeze

[shoot-n-lead]

I have a sackful from years past and they are all fine, very consistent throats...shoot great groups.

Never heard of many having the problem that yours did...oh, well.

[white eagle]

I have a flat top Blackhawk 44 special and the throats are
all the same size
I checked them with pin gauges
it shoots like a champ it is one revo that will last

[Dale53]

My two Ruger Flattops have good throats and will, on demand, put five shots under an inch at twenty-five yards off a rest. I consider them amongst the best revolvers Ruger has produced.

FWIW,
Dale53

[MT Gianni]

My 44 Blackhawk special is the second most accurate revolver I own out of 15 or 16. I have done nothing to it.

[DougGuy]

All of the new model flattops are great. Most have even enough throats but there have been a bunch sent here for reaming that weren't even so it is hit or miss how even they are.

Well worth the investment to have them all sized evenly since this is the single most important part of the cylinder, even more important than the throat size. You can always size to fit the throats, but uneven throats will always take away from the groups regardless of what you size to simply because it affects pressures quite a bit from shot to shot.

[rintinglen]

My two Ruger Flattops have good throats and will, on demand, put five shots under an inch at twenty-five yards off a rest. I consider them amongst the best revolvers Ruger has produced.

FWIW,

Dale53

I agree totally. Mine is by far the most accurate 44 Special I have ever owned.

[W.R.Buchanan]

Doug guy: Are you "reaming" the throats of cylinders sent to you, or are you honing them on your Sunnen Hone?

Do you have a "Sunnen Hole Gage" to really dial in the holes?

Unfortunately they are not even giving the well used ones away. Here's one on Ebay. http://www.ebay.com/itm/SUNNEN-PRECISION-HOLE-GAGE-MODEL-PG-800-S-740-TO-1-500-370-TO-740-/351847154159?hash=item51ebb981ef:g:PLgAAOSwPCVX4Wx t

This one is a .750 to 1.500 range but they have them from .250 to 1.000 just different probe fingers.

Randy

[DougGuy]

I prefer to ream the holes first as the reamer cuts consistently round holes, then hone to finished size with the Sunnen hone. I have one of those high dollar gauges on my Sunnen but don't have the small diameter fingers for it. I checked into the midget point set for mine and it only goes down to something like .375" or .400" at the small end, and to .700" at the big end which would only let me do half the cylinders that come in the door. I think they make a PG-700 gage that will go down smaller but man it cost more than my whole hone machine and all the tooling added together just for that gage.

Don't really need the Sunnen gages as you do enough cylinders on it and you get a feel for how much the hone is taking out and with the very fine stones I use it ain't much. They cut slow. I keep gage pins with the hone so I can check sizes as I go.

Some cylinders I have to do on the hone all the way because I don't have the exact reamer I would use for it, these take a little more time because you have to figure out which throats are the largest and you have to work the others up to those so they all come out even.

I have a Dorsey dial bore gage that reads in .0001" increments with a range from .248" to .510" but I rarely even need to break it out. The pin gages I use are Z minus sets, in both thousandths and half thousandths which is a pretty fine set of increments and is really all that is necessary to do revolver cylinders.

For example, if a .3585" pin goes in the throats and it is smooth and even in each throat, and a .359" won't go in any of them, the throat is between .3585" and .3588" which is exactly what I would shoot for on a .35 caliber cylinder. As long as they are even with each other, and I try to send them out within .0002" of each other, I feel that the difference between .3585" to .3588" or .4525" to .4528" is negligible and there likely isn't a shooter alive who could detect the difference. Hell there probably ain't even a Ransom Rest alive that could tell .0003" as long as all the throats were the same.

Cast boolits will grow as they age harden and it's very common, depending on how much antimony is in the alloy for a .44 or .45 caliber boolit to gain .0003" to .0006" in diameter as they sit and harden off. I like to send cylinders out with at least enough "wiggle room" to accommodate the age hardening, a bit of excess lube here and there, parting line still on the boolit, etc.

In a perfect world, the cast boolit would be .001" to .002" greater than groove diameter of the barrel, and the throats should be .0005" to .001" greater than boolit diameter. This arrangement works very well and I pretty much adhere to these dimensions when I suggest finished throat sizes and boolit sizes. It just works.

[W.R.Buchanan]

OK: thanks for the run down and I agree with your assessment of pin gage fits. I have a bunch of oddball Delton pins I got in a machine shop buy out I did. They are dead nuts and I sometimes use them to check mic's for calibration.

When building my first run of Hand Presses I ran into Drill rod that was on the high side of .3755. The holes were .375 so I had no choice but to ball size the holes to .376. I found and outfit in LA that made precision balls in just about any size you could want.

They had one problem, they had a Standard that they calibrated all their instruments to, and this thing was supposed to be calibrated to a National Standard and traceable to God himself. However it was wrong and it took some convincing over the phone to get them to check it.

For an outfit that dealt with .000050 everyday they didn't like me telling them that my Micrometers, an Etalon and a Tesa, which I checked with Jo-blocs were more accurate than their $100K machine.

Then they apologized and sent me balls that were in fact .376 which I proceeded to shove thru the holes so that .3755 rods would go in.

Subsequent batches of parts are reamed to .376 and go together nicely.

The Sunnen Hole Gages are pretty accurate pieces of equipment, a lot of guys in my area had them as everybody was doing Aerospace Work on Hardinge Chuckers back in the day (1980's)and needed the most accurate measuring tools they could get.

Randy

[ironhead7544]

Had 2 Flat Tops. Both were .429 barrels and .430 throats. Very accurate.

[Fernando]

Mine are .431 all six in one and I have one with 4@.431 and 2@.432
Pin gauges used.
Swaped top ends to get a 5.5 Bis and 4 5/8 plow.
My 4 5/8 has a thread choke and I'll lap that out this fall.
The 5.5 shoots lights out.

[flint45]

I wish ruger buit the cyl. on there .45s as good as there .44 spl cyl mine all 6 holes .430 barrel .429 shoots lie a houseafire.

[nicholst55]

I wish ruger buit the cyl. on there .45s as good as there .44 spl cyl mine all 6 holes .430 barrel .429 shoots lie a houseafire.

I was just about to say the same thing! I traded for a Lipsey's special Ruger .45 convertible flattop, and just finished reaming both cylinders. The largest of the 12 throats was .451". That gun also suffers from transfer bar pinch and a thread constriction. I think I discovered why the previous owner was so anxious to trade it! My .44 Spl flattop was dead on as far as chamber throats and bore diameter goes.