RUGER 45 convertible large chambers

[Chill Wills]

I have a Ruger 45 convertible 45 Colt - 45 ACP I got new in the late 1970's. For years I shot cast bullets in it -as cast- which were more or less 0.452" with 10 yard accuracy that was just Okay and nothing more. My Super Blackhawk was much more accurate and was my plinker of choice. To see what was going on, I had run soft 50 cal round balls through the cylinders and found 0.456 and 0.457" diameters. The ACP cylinder is large too! Goofy.

LBT made me a 4 cavity 45 Colt mold of the correct nose profile to match the factory stuff and at his suggestion a much larger diameter. The mold casts great bullets at 0.457+. The handgun as been living in the back of the safe for 30 years because it is just not a great gun. I started working with it off and on the last few years and found the RCBS seating die is not large enough to seat the 0.457" bullets with out shaving the bullets on the way in despite the fact I have a custom expander that opens the case to 0.456" and flairs the mouth to 0.460". Accuracy with the shaved bullets is not all that great either.

In any case, I am going to be shooting 0.457" bullets through a 0.452" barrel.

I am thinking about trying to make a die body slightly larger just to seat the bullets. Any advice on going this route?

[Char-Gar]

Have you actually measured the chamber throats and if so how? The problem with Rugers in 45 Colt, was throats were to small and not to big. The throats ran .450 - .451 for use with jacketed bullets. The actual chamber, not the throat, ran on the large size. Unless your handgun has been messed with or is some kind of a unicorn, you are going the wrong direction with your bullet sizing. The cure is to open up the throats to .4525 or thereabouts.

[gpidaho]

C.W. That's interesting. All my Rugers have come to me with tight throats. My 45 Blackhawk convertible came to me with .451 throats on both cylinders. (Measured with pin gauges) Maybe someone out there has a Redding competition seating die and can measure how large a bullet it will accept. I have three that that will accept bullets two or three thousandths larger than standard seaters. Gp

[Chill Wills]

Have you actually measured the chamber throats and if so how? The problem with Rugers in 45 Colt, was throats were to small and not to big. The throats ran .450 - .451 for use with jacketed bullets. The actual chamber, not the throat, ran on the large size. Unless your handgun has been messed with or is some kind of a unicorn, you are going the wrong direction with your bullet sizing. The cure is to open up the throats to .4525 or thereabouts.

Thanks for the reply. I addressed your question in the first paragraph. Maybe less than clear... the throats were large. I also confirmed my findings with pin-gauges.

[shooting on a shoestring]

Chill, right there with you.
I have a 45 Colt Blackhawk that also has 0.456 throats (chamber exit holes). It was Dad’s. He traded for it late in life after shooting and getting to like my 45 Colt Blackhawk. Mine shot ok, but shot better after I reamed the throats to 0.454” uniformly. He liked mine so he got one. I never messed with his until after he passed. Yep those throats are 0.456”. Measured by me with Starrett Split Balls and a 0-1” mic. And yep I know how, and am able to take ID measurements in small holes with them. Split balls are a better tool for throats than pin gauges bc split balls allow you to measure how much out-of-round the throats are. Pin gauges just tell you what’s the smallest round diameter that will go in the egg shaped holes.

[shooting on a shoestring]

Made me curious, so I found the gun, pulled the cylinder and measured the throats.

The first measurement is measured in the axial direction. That is the direction running from the arbor bore (center of the cylinder) outward towards the OD of the cylinder. The second measurement is 90 degrees to the first. That is in the direction from one neighboring chamber to the other neighboring chamber.

1. 0.4566-0.4561”
2. 0.4562-0.4561”
3. 0.4564-0.4559”
4. 0.4563-0.4559”
5. 0.4568-0.4561”
6. 0.4562-0.4561”

The chambers all carry blue and it looks like factory blue inside the chambers and throats. I really think this cylinder came from Ruger with 0.456” throats.

[shooting on a shoestring]

Now as how to load 0.456” or 0.457” boolits for it?

I haven’t yet. But…..if I wanted to try, I’d try sacrificing a Lee 45-70 seater die and cut off about half the length with a thin abrasive blade in an angle grinder.

But first I’d measure the inside diameter of the muzzle end of the chamber and see if there’s room for a 0.457” boolit plus 2 thickness of brass case wall plus some clearance for allowing the ammunition to load without thumb pressure. If so, this might work. If not, time to open up the chamber ID by either dowel and emory, or chucking reamer. Either way there will be a high risk of screwing up the cylinder worse than it is…..which really wouldn’t be a great loss.

[Char-Gar]

Now as how to load 0.456” or 0.457” boolits for it?

I haven’t yet. But…..if I wanted to try, I’d try sacrificing a Lee 45-70 seater die and cut off about half the length with a thin abrasive blade in an angle grinder.

But first I’d measure the inside diameter of the muzzle end of the chamber and see if there’s room for a 0.457” boolit plus 2 thickness of brass case wall plus some clearance for allowing the ammunition to load without thumb pressure. If so, this might work. If not, time to open up the chamber ID by either dowel and emory, or chucking reamer. Either way there will be a high risk of screwing up the cylinder worse than it is…..which really wouldn’t be a great loss.

First thing I would do is try sending it back to Ruger for a new cylinder. That may or may not work. If that doesn't work, I would try Ebay. Easier to make a hole larger than smaller.

[Chill Wills]

Now as how to load 0.456” or 0.457” boolits for it?

I haven’t yet. But…..if I wanted to try, I’d try sacrificing a Lee 45-70 seater die and cut off about half the length with a thin abrasive blade in an angle grinder.

But first I’d measure the inside diameter of the muzzle end of the chamber and see if there’s room for a 0.457” boolit plus 2 thickness of brass case wall plus some clearance for allowing the ammunition to load without thumb pressure. If so, this might work. If not, time to open up the chamber ID by either dowel and emory, or chucking reamer. Either way there will be a high risk of screwing up the cylinder worse than it is…..which really wouldn’t be a great loss.

My real question is about me thinking about making a new die body a few thousands larger to see if I can seat these large bullets with out shaving. Spitballs ...Starrett Split Balls. I had not heard that slang before :razz: I have a set too. If I make and bore out a seater die body I will be using them. We are on the same page. I have been rolling the inside machining in my head before I get started. I think I've got it worked out with a crimp.

[Chill Wills]

Sending it back to Ruger has always been an option. It might happen. But first I am interested in seeing what can be done through loading larger ammo. This isn't life and death. It is an interesting hobby.

[Nueces]

I have the same issue, large throats, with several revolvers. My way of dealing with tight seating dies is to use the Hornady sliding sleeve seater die. The sliding part is a simple cylinder, easy to bore or ream out for larger case necks. I've also bought some steel rod for making these slides. Of course, a small lathe makes short work of all this, but a reamer could do the job for one gun.

[higgins]

I had an early 1980s .45 convertible Blackhawk that also had .456-.457 chamber mouths and a .452 groove bore. It shot best with unsized 454190 bullets that were about .454 as cast. Other bullets of around .453 diameter did OK if they were loaded with fast burning powder or Unique.

After I got educated on this site about the relationship between chamber mouths related to groove diameter, I sent the gun back to Ruger about eight years ago with both cylinders, asking them to fit cylinders with smaller chamber mouths. I don't know if they no longer had the proper cylinders in stock, damaged something, or just gave up trying to improve cylinder mouths, but they couldn't get the gun "to target". I've read that there have been minor dimensional changes in Blackhawk cylinders over the production life of the gun, but I don't know enough about Blackhawk history to confirm that.

Anyway, they ultimately offered me the option of returning my gun "as-is" or send me a replacement. I opted for the replacement and got a gun with more appropriate cylinder mouth diameters that shot well and had a better trigger than the old gun. There are times I wish I had kept the older Blackhawk because I had shot it so much that I got attached to it, it didn't shoot that badly, and a replacement with 7.5" barrel was not available at the time. I got used to the 5.5" barrel replacement and it is generally more accurate so I guess it worked out in the end. If I had it to do over I would have worked with bigger diameter bullets before I returned it.

[kingrj]

Very interesting! I have an old 3-screw BlkHawk convertable .45 that has oversized "chambers" but had 0.450 throats! I rented a reamer to fix the tight throats but nothing I can do about the chambers...Cases fired in the old 3-screw will not chamber in my Linebaugh "small" .45 Colt....But the old guns shoots like a house-a-fire though!

[Doughty]

Chill Wills,
I have a .45 Colt Blackhawk such as yours. I shoot .457 bullets in it. I also have a Marlin rifle in .45 Colt. The Marlin has a very oversize chamber and will shoot .461 bullets the best, but will shoot .457 bullets nicely. I load ammo to be used in both guns on a Lee Loadmaster. In station 1, I use a Lee .45 Colt carbide die. I ground the carbide ring out on my lathe with a diamond impregnated internal wheel. It sizes the brass to just nicely chamber in the Blackhawk. In Station 2, I have another Lee .45 Colt carbide die that is ground out to size the brass to an ID of about .455. I adjust this die to only size the brass to the depth of the seated bullet. In the powder through die I made the expander/bell insert to expand to .456 and bell enough to easily start the .457 bullet. The Lee standard seater seats the bullet to depth. The last die is a Lee FCD for the .45 Colt "RIFLE" (no carbide sizing ring) that crimps the bullet in place. This gives me good ammo that loads and shoots good in both guns. Complicated maybe, but it works.

[Cosmic_Charlie]

You really can't fix that. Gun will always be sub par. Sell it and move on.

[Thumbcocker]

If you can find some of the soft hollow based factory boolits they might work as a stop gap. I would look for new cylinders from Ruger myself.

[Nueces]

In my early days of casting for large throat 45s, a Smith 25-2 being the first, I used the Lyman 452490 SWC with a gas check. They rattled down the large throats, but produced good accuracy and little leading. I know better now, but that worked back then.

For the yawning 2Gen Colt SAA in 45, the Remington hollow base factory slugs thoroughly filled the throats and were wonderfully accurate, but splashed soft lead all over the back of the barrel. The last Midway price for a carton of 500 of those ran $129 and they have been out of stock for years now. For smaller chambered revolvers, I used these after running them through an early set of CH 101 swaging dies.

[DougGuy]

I had a BH convertible back in the 80s, it too had .456" throats. I sent it back to Ruger and asked them for two cylinders with .4515" throats and when it came back VOILA!!! .4515" throats! All on their dime.

Here's the deal.. If you call them and tell them it won't hit a fat hog in the ass with factory ammo, and that you would like to send it in and let the factory check it out. They test fire it and it doesn't group for them, you will get two new cylinders fitted on their dime including shipping both ways. Call their customer service and butter them up about how good they are, best in the industry, yada yada, and you will sweet talk them into sending the brown truck to pick up your BH and take it back to the factory.

Once you get it back then see how big the throats are and go from there.

OTOH, my avatar pistol is a Uberti Old West model with .4565" throats and .451" barrel. I size to .456" and it's accurate and no leading. Boolit is a 454190 cast in 50/50+2% with soft lube, I made a custom expander plug for the powder die and standard 45 Colt loading dies work well. This gun will shoot the wings off a fly at 10 yards, so I know sizing down isn't an issue, but you MUST have consistent throat diameters or all bets are off.

[robertbank]

I would not putup with or try to solve to large of tcylinder throats. .456 are out of spec. Ruger will make it right.

Take Care

Bob

[JCM45]

I had the same problem. My 45 Colt Blackhawk has .454 chamber throats in which I load a .455 cast bullet. The case mouth flair required to accept this bullet is too large to enter a standard 45 Colt bullet seating die. I solved this with a 480 Ruger bullet seating die set to seat the bullet only. I then crimp with the Lee 45 Colt collet crimp die. Problem solved.

[JCM45]

I sent my Blackhawk to Ruger under a warranty claim, requesting a new cylinder with smaller diameter cylinder throats. They told me that .454 is within tolerance and sent the gun back to me without a new cylinder.

[cabezaverde]

I had to send mine back for a transfer bar replacement. On a whim, I sent the cylinders and complained about the oversized throats - greater than .456" on the colt cylinder.

It came back with two new cylinders and a new transfer bar.

[243winxb]

Cast some bullets with Linotype & size to your groove diameter + .001" at the most. Puts a stop to skidding & slump. Test .

I opened a RCBS 45 acp seating die with a wood dowel & emery paper. But you have a LOT OF METAL to remove.
Making a die may be easier?

[Texas by God]

This makes me wonder if that was the problem with my friends late 70's BH .45 Colt. Side by side shooting with my BH .41 mag was embarrassing for him. My Star PD.45acp would also out shoot it with any load I came up with. He sold it and when he got into CAS years later, he bought Uberti 1873 SAA- a pair- and a .45 Colt Uberti 73 Winchester clone. Those three were great shooters.

Sent from my SM-A716U using Tapatalk

[DougGuy]

Cast some bullets with Linotype & size to your groove diameter + .001" at the most.

And shoot these through throats .005" bigger? Laughable advice.

Many years ago, the same BH I referenced in this thread in an earlier reply, with .456" throats, I fed it EXACTLY what you are recommending. I used near pure lino boolits, sized maybe .451" which was the same as groove diameter. I DESTROYED a Lewis Lead Remover with a ball peen hammer trying to de lead the barrel. It was HORRENDOUS. Unbelievable leading.

I would not suggest the OP do the same thing.

[Outpost75]

I am getting really tired of reading the same old Lyman disinformation about using hard bullets sized to the groove diameter of the barrel. Keith had it right in his Sixgunner452 Cartridges and Loads, 1935.

[Chill Wills]

Thinking aloud here. I think this is my plan.

For my own interest I am going to record a few targets shot with the ammo made with the RCBS 250 grain SWC - Diameter 0.452". That mold is long gone but I still have some bullets from it.

8grs of Unique has been my long standing load in the 45 Colt with 250 grn bullets.


I am goin to make a seater die to seat the 0.457" LBT 255 grn bullets without shaving them and record how that groups. 8grns Unique

At that point I may contact Ruger to see if they are interested in addressing this BH. DougGuy's well thought out aproch outlined in the above post sounds like the voice of experence. I can use that as a guide. If Ruger takes it back and refits it with new cylinders, I can compair it with the earlier targets shot with the large cylinders.

I find it interesting as a project.

[243winxb]

Hard bullets deform less when they hit the forcing cone. Lyman has said sizing down more then .003" will hurt accuracy.

Sizing by die or forcing cone, SAME.

Do your own testing as always.

https://www.thehighroad.org/index.php?media/44-magnum-hard-alloy-25-yards.3117/full

[DougGuy]

Lyman has said sizing down more then .003" will hurt accuracy.

Sizing by die or forcing cone, SAME.

That Lyman info is pure BS. What hurts accuracy and leads the crap out of a gun is firing boolits undersized to the throats.

Want proof? Take the SAME boolit, cast larger and size them to your cylinder throats as you posted them at .432" and watch that group shrink.

[Outpost75]

Sizing more than 1% of bullet diameter with the Lyman bullet base and nose deformer and in the case of heavy bullets, also a body bender, does hurt accuracy, but due to inherent design defects of the antique machine. If bullets must be sized they should be pushed through the die nose first. But best is to have bullets drop to correct diameter so that no sizing is needed.

[DougGuy]

Sizing more than 1% of bullet diameter with the Lyman bullet base and nose deformer and in the case of heavy bullets, also a body bender, does hurt accuracy, but due to inherent design defects of the antique machine. If bullets must be sized they should be pushed through the die nose first. But best is to have bullets drop to correct diameter so that no sizing is needed.

Shooting as-cast boolits can be good or it can be hit or miss because you often have parting lines which makes the boolit larger on one tangent than the other tangent so it is in effect an oval of sorts, which could work either way, you could get some interference if the oval part is larger than the throat, or you could get some gas bypassing the boolit if it is significantly smaller than the throat but with a soft alloy and soft lube, if you load over a decent enough powder charge, you could get obturation to bump the boolit to throat diameter in which case you could not ask for a better fit in the throats.

Even when I have boolits that I know are sized and lubed correctly, I STILL run them through a push through die just to weed out any inconsistencies before loading.

[Chill Wills]

I machined a new seating die to except the larger diameter bullet. Basically I used the RCBS die as a pattern and improved the new one to meet the needs of the oversized ammunition. I took the time to load 12 rounds and it works well, seating the 0.457" bullets into the cases without pinching the case before the bullet could be seated. The old die was closing the expanded mouth back down before the 0.457" diameter bullet had a chance to get into the case. And that was sheering a ring of lead off the side of the unseated bullet.

In the picture of the empty case and loaded round, you can see the scuffed brass as the case and bullet combined diameter was too large for the RCBS die to swallow. This resulted in lead shaved during seating as well as pinching the case - reducing the bullet in the die.

[Chill Wills]

Ammo loaded in the new seating die. No shaved rings. No pinched brass. The five loaded rounds are three Starline in the middle and two R-P cases on the ends. The R-P cases work well. The Starline must have slightly thicker case walls. The R-P cases are a joy to load and the crimp comes out better. As the cases show, the crimp on the Starline cases still needs some work.

[243winxb]

That Lyman info is pure BS. What hurts accuracy and leads the crap out of a gun is firing boolits undersized to the throats.

Want proof? Take the SAME boolit, cast larger and size them to your cylinder throats as you posted them at .432" and watch that group shrink.

Been tested. Big soft = poor accuracy. Do you own testing,i have.https://www.thehighroad.org/index.php?media/44-magnum-soft-alloy.3118/full

[243winxb]

Ammo loaded in the new seating die. No shaved rings. No pinched brass. The five loaded rounds are three Starline in the middle and two R-P cases on the ends. The R-P cases work well. The Starline must have slightly thicker case walls. The R-P cases are a joy to load and the crimp comes out better. As the cases show, the crimp on the Starline cases still needs some work.

Nice job on the die work.

¹Waiting for the accuracy test. Before and after. What alloy are you using ?

[Larry Gibson]

I seldom disagree with outpost75 but I do here. My testing years back with the 44 magnum [Hawes SAA & S&W M29] the 45 AR/ACP [S&W and Colt M1917s and a S&W M25] and the 45 colt [Colt SAA and Colt New Service] in revolvers using a Ransom Rest with the target at 50 yards gave solid evidence on target that cast bullets that were .003" or more over groove diameter did indeed give less less accuracy than even the same bullet sized just .001 over groove diameter.

For years before Venturino (?) wrote the article on oversize bullet being "more accurate" I had shot .356 sized 9mm cast bullets in 9mms, .358 cast bullets in the 38 SPL and 357, .429 sized cast bullets in the 44 SPL and 44 magnum and .452 sized cast bullets in the 45 ACP and 45AR. Accuracy was excellent with me be able, back then, to regularly shoot 1 - 1/2" 5 shot groups at 25 yards from a sand bag rest.

When I started shooting PPC I had a wonderfully accurate PPC revolver made by Power Custom on a M10 S&W action. I, like most all PPC shooters quickly found it was almost improbable if not impossible to duplicate the accuracy of Remington and Federal 38 SPL WC match ammo at 50 yards with my own WC cast bullet loads. That was the WCs fitting the throats of the cylinder at .457". I used an inertia bullet puller to see how "perfect" the factory WCs must be. They looked like regular Swaged WC we could buy. The weight variation was on par with my cast WCs but .....they were .355 - .356 diameter! I though the mild crimp may have swage them down so I cut the case behind the crimp and inertia puled 5 more.....they were the same diameter .... .355-.356! They were .001 -.002 under the throat diameter yet they gave no leading and were exceptionally accurate with no leading [most top PPC shooters used factory match WCs only at the 50 yard line].

So I ignored my own testing experience and went with the gun writers insistence that over sized bullets that "fit the throat" always gave improved accuracy and began using them myself. I quickly found if the bullets were .003"+ over groove diameter of the barrel to fit the cylinder throats accuracy would not be as good as with bullets just .001 - .002 over groove.

Why we ask? Well if we actually measured the diameter of fired undamaged lubed cast bullets we would find they can be .001 - .005 under groove diameter even if they started out .003 over groove diameter. Why is that? Because the bullet rides over a layer of lube is why. That lube thickness swaged the bullet down also. Thus if we start out with a bullet that is .003 over groove it can get swaged down .4 - .006+ under groove diameter. If we swaged/sized the bullet down .--1+ to make it throat diameter before loading it's even more.....That much swaging down does not do the concentricity of the bullet any good and, additionally, the base is "finned" pretty bad. All of which does not contribute to accuracy [precision].

As to the cause of "leading" in revolver cylinder throats and bores the use of an improper lube is most often the culprit.

Sorry it disagrees with you guys but that is what I have found. Thus I have gone back to .356 bullets in my 9mm's, .357 bullets in my 38 SPL and 357s, .430 bullets in my 44 Magnums and .452 bullets in my 45 ACP, AR and 45 Colts

The 3 most accurate revolvers I have right now [ Ruger 41 Magnum, Ruger 44-40 OM Vaquero and Colt Anaconda 44 magnum] all have throats the same diameter as the groove diameter [.410 in the 41 magnum and .429 in the Vaquero and Colt 44 s] so the bullets are sized .410 and .429. No leading and superb accuracy...way better than I can hold anymore.

[243winxb]

I seldom disagree with outpost75 but I do here. My testing years back with the 44 magnum [Hawes SAA & S&W M29] the 45 AR/ACP [S&W and Colt M1917s and a S&W M25] and the 45 colt [Colt SAA and Colt New Service] in revolvers using a Ransom Rest with the target at 50 yards gave solid evidence on target that cast bullets that were .003" or more over groove diameter did indeed give less less accuracy than even the same bullet sized just .001 over groove diameter.

For years before Venturino (?) wrote the article on oversize bullet being "more accurate" I had shot .356 sized 9mm cast bullets in 9mms, .358 cast bullets in the 38 SPL and 357, .429 sized cast bullets in the 44 SPL and 44 magnum and .452 sized cast bullets in the 45 ACP and 45AR. Accuracy was excellent with me be able, back then, to regularly shoot 1 - 1/2" 5 shot groups at 25 yards from a sand bag rest.

When I started shooting PPC I had a wonderfully accurate PPC revolver made by Power Custom on a M10 S&W action. I, like most all PPC shooters quickly found it was almost improbable if not impossible to duplicate the accuracy of Remington and Federal 38 SPL WC match ammo at 50 yards with my own WC cast bullet loads. That was the WCs fitting the throats of the cylinder at .457". I used an inertia bullet puller to see how "perfect" the factory WCs must be. They looked like regular Swaged WC we could buy. The weight variation was on par with my cast WCs but .....they were .355 - .356 diameter! I though the mild crimp may have swage them down so I cut the case behind the crimp and inertia puled 5 more.....they were the same diameter .... .355-.356! They were .001 -.002 under the throat diameter yet they gave no leading and were exceptionally accurate with no leading [most top PPC shooters used factory match WCs only at the 50 yard line].

So I ignored my own testing experience and went with the gun writers insistence that over sized bullets that "fit the throat" always gave improved accuracy and began using them myself. I quickly found if the bullets were .003"+ over groove diameter of the barrel to fit the cylinder throats accuracy would not be as good as with bullets just .001 - .002 over groove.

Why we ask? Well if we actually measured the diameter of fired undamaged lubed cast bullets we would find they can be .001 - .005 under groove diameter even if they started out .003 over groove diameter. Why is that? Because the bullet rides over a layer of lube is why. That lube thickness swaged the bullet down also. Thus if we start out with a bullet that is .003 over groove it can get swaged down .4 - .006+ under groove diameter. If we swaged/sized the bullet down .--1+ to make it throat diameter before loading it's even more.....That much swaging down does not do the concentricity of the bullet any good and, additionally, the base is "finned" pretty bad. All of which does not contribute to accuracy [precision].

As to the cause of "leading" in revolver cylinder throats and bores the use of an improper lube is most often the culprit.

Sorry it disagrees with you guys but that is what I have found. Thus I have gone back to .356 bullets in my 9mm's, .357 bullets in my 38 SPL and 357s, .430 bullets in my 44 Magnums and .452 bullets in my 45 ACP, AR and 45 Colts

The 3 most accurate revolvers I have right now [ Ruger 41 Magnum, Ruger 44-40 OM Vaquero and Colt Anaconda 44 magnum] all have throats the same diameter as the groove diameter [.410 in the 41 magnum and .429 in the Vaquero and Colt 44 s] so the bullets are sized .410 and .429. No leading and superb accuracy...way better than I can hold anymore.

My finding also. I learned using the Lyman cast manual from the 70's .

[Chill Wills]

By the posts here and information elsewhere it appears 45's with large throats mostly come from one manufacturing era. Ruger must have been aware of the problem and then corrected it. Maybe over compensated. It is hard to imagine being this far off when they are capable of getting hundreds of thousands of things right in the course of making all their products. Not having ever worked in that type of business I am sure I don't know the half of it.

243winxb - the alloy most often used for all my handguns was WW with 1-2% tin added. Sometimes it would be 20-1 Pb-Sn. Both with about the same result. Only rarely did I experiment with lino in the hot 44 mag. In my whole life I have shot very little "full out: 44 mag loads.

A few people say they like pictures of the machining.
There are guys here that have a lifetime of professional experience cutting steel. I am sure they roll their eyes at us hobby types and how we do things, but still, it is good to be able to do some of this. Not a week goes by that I don't use my lathe and mill to address some problem around here - not just firearms.

[Chill Wills]

I had time enough today to shoot the four 5-shot targets. Little can be concluded with so few shots. Still interesting.

[DocSavage]

The 2 Ruger Blackhawks I have has had 2 things done throats open to .452 and fire lapped the bores on both. I admit to not being the world's best pistol shot but I can say leading has ben drastically reduced using my cast bullets sized at .454.

[Forrest r]

https://i.imgur.com/3f6cvSV.jpg

Any of those bullets would work in the over sized cylinder holes. Sold 3 of those molds off and still have the bullet mold picture above/bottom left. It's a cramer 5f bullet that has hb pins in the mold. It was designed to be used in the oversized 1917/45acp surplus revolvers.. It casts a .4535"/.454" nose pour bullet with range scrap alloy.
https://i.imgur.com/DuFFJCS.jpg


Probably should of kept the raphine hb mold (top left bullet top picture) 454155. Had raphine hb molds for the 35cal's/44cal's & 45cal's. Ended up selling them all, used to keep them around in case I bought a firearm that needed oversized bullets. Been thinning the herd with firearms/molds/swaging equipment/etc.

I don't envy you guys that are walking a tight rope balancing oversized bullets/cylinders vs normal bbl diameters. Never have been a big fan of sizing bullets down more than 3/1000th's in a sizing die or a bbl.

At 1 point I owned over 14 hb molds along with swaging equipment to swage my own hb bullets for the 32/35/44/45cal's. Did a lot of testing with different hb shapes/designs making my own hb pins for molds and swaging dies.
FWIW:
Shot countless 1000's of hbwc's in the 38spl's, either store bought or home swaged along with casting them also. Same with home case wc's, I always sized my swaged hbwc's, cast hbwc's, cast wc's to .357" & still do to this day. Everything else gets sized to .358".

OP:
You might consider doing a little testing with hb bullets. You have the equipment, make a simple swaging die like this one.
https://i.imgur.com/bG7YKsc.jpg

Nothing more then some scrap round stock, a bolt & washer. The cast bullets are lee 311-93-1r cast out of pure lead then lubed. Then tossed in the swaging die and using a arbor press swaged into a .314" hbwc. Made those to test a .314" bullet before buying any molds.

Same thing can be done with making a collet for your lathe and drilling a hb in cast bullets to test.

If .452" ain't cutting it and .457" seems to deform the bullet too much when swaged/sized down by the bbl. A .453"/.454" hb bullet might be your best option.

[Cosmic_Charlie]

To top it off, thread choke is fairly common on big bore revolvers and that would exacerbate an already undesirable condition. Be great if Ruger steps up for you.

[MostlyLeverGuns]

Bought an early 3-screw Ruger Blackhawk .45 convertible in the 70's, sold in the 80's. Little information on what made revolvers accurate in those BEFORE INTERNET days. Never could get that revolver to shoot, that was why it was sold. Maybe today I could figure it out. In 1968, right before that first Federal law of 1968 I bought a Hawes Colt clone, made by Sauer & Son, it was very, very accurate, very well made. I thought the Ruger would be better, but I still miss that Hawes .45 convertible. Haven't chased after a Ruger since that first 3-screw .45. I have a 3-screw Single Six that is accurate with both 22 LR and 22 Mag but that was before the .45.

[Chill Wills]

Forrestr that is a lot of interesting information. Thank you for putting it out here!

I may try the HB with a few test bullets.

Also, I do own the Lyman 457 195 HB 225gr. Something of a rare mold. However, it is a 0.457" and not exactly like using the smaller 0.454 bullets HB to match the barrel. I get the concept.
I may try using some of the 452-374 45 ACP bullets and HB some of them.

I need to try the system I made a little more - give it a full test to see what the large diameter bullets can really do before giving up.

I fully agree with those who advise simply send the revolver back to Ruger and see if it can be made correct. Case closed.

When the fun stops fooling with it as is, that may be the final step.