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 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.