Question on 45 long colt throats honed shooting factory and cast boolits

[Whitetailsniperkirk]

I have a question I feel I will get honest and correct answers to, I reload, and cast. I have a newly recent purchased Ruger Blackhawk ( new model) in 45 long colt with a 4 3/4 inch barrel. Now knowing that the rugers cylinder throats are all not same size, I am considering sending my cylinder out to be honed. So taking in consideration I reload factory bullets like .452 hornady xtp as well as Barnes bullets .452 I have 2 miha molds from mp molds that cast out a cast bullet diameter of .454 I have 2 lube sizer dies in .452 and .454 Now taking in consideration of both types of Bullets both factory and cast, What size should my cylinder throats be honed to ???? Your help and advise is greatful.

[Wheelguns 1961]

.4525” for the throats. Shoot .452” bullets. What size are your throats now? There is a man on here that goes by Doug Guy. You should get in contact with him.

[Whitetailsniperkirk]

I have been talking with him, and he says .4525 I’m just wanting second opion because I was told in past that when casting you always want to size .002 over what the caliber diam is for cast bullets
I’m just making sure this is correct

[stubshaft]

Ream it to the largest chamber in your cylinder, you can size bullets to fit. This is assuming that the cylinder chambers are LARGER than the bore. Not always assured with a Ruger.

[DougGuy]

Ruger 45 caliber barrels have been right at .451" groove diameter for years and years and years. Some like to size to the same as the groove diameter, I do not suggest this because sizing .001" to .002" over gives enough lead to swage the boolit to a better seal in the barrel. And it's quite obvious that regardless of what you size the boolit to when you assemble ammo, they will be swaged down by cylinder throats that are smaller than the boolit. The cylinder is nothing more than a multi port sizing die at this point, as boolits will leave the front of the cylinder at throat diameter.

You size the cylinder throats .0005" to .001" greater than the boolit diameter, this, and ONLY this will assure you are delivering to the barrel, the boolit as sized, and assembled.

Match them all to the largest throat? What if that throat is not quite as large as the boolit already? Now you have gone to the effort to match all the throats but they are still smaller than optimum, and if they are all .4505" or .451" or .4515" when you get done, then you are still down sizing the .452" boolits as they are fired. There are so many suggestions made by those who understand enough to know that maybe some cylinder throat work is needed, but don't completely understand why certain dimensions work best and others well, they may work but not quite as well.

I would say 95% of handloaders that are loading for a 45 caliber handgun, choose .452" as their desired diameter, and probably 98% of all the 45 caliber cylinders that are sent in are sized to .4525" with the exceptions being cylinders that throats are already larger than .4525" from the factory or cylinders that are badly pitted, or Bubba got hold of them with a split dowel and some sandpaper in an electric drill.

In a perfect world, a revolver boolit would be sized .001" to .002" greater than groove diameter, and the cylinder throats would be sized .0005" to .001" greater than boolit diameter. This arrangement works in every centerfire cartridge made for revolver, regardless of caliber, it just works across the board for shooting cast lead alloy boolits.

Having the boolit larger than groove diameter makes a better seal than one same size or smaller, throats at least the size of the boolit or larger makes sure the boolit isn't sized down on firing. Simple as that.

[sharps4590]

I like Doug!!! My sentiments exactly..

[bedbugbilly]

Doug is the chamber throat guy and his reputation speaks for itself.

I can't speak to the Ruger you have but I had a Ruger New Vaquero in 357 - worst shooting revolver I've ever had out of the box as throats were all over the place. I sold it as I personally didn't like it and went with a Uberti Bisley. The guy who bought the NV from me knew it needed a ream job- he got it done and is still enjoying the way it shoots now.

A different horse, but I have a 45 Colt Cattleman - I have a number of molds I cast with - some .452 and my 454-190 drops them at .454. My throats are .4545 and for the shooting I do - it shoots both .452 and .454 equally as well. Keep in mind that I am using soft lead - no plated or jacketed - and not pushing them hard. My cattleman is a 7 1/2" barrel and I sometimes amaze myself at how well it shoots at 50 yards on paper and killing cans.

I have never measured the throats on my 4 3/4" Uberti Bisley, but it has been an accurate shooter right out of the box. I use a number of molds and J rarely size - I shoot them as they drop. The largest one I use drops at right around .359 - .3595 - they gently slide into the cylinder throats so I'm guessing the throats are probably right around .360 - .3605 or so.

My point is that you can't take a boolit/bullet that is bore size or .001 - .002 over bore size, shove it through a throat that is smaller than bore size and then expect it to expand when it is going down the bore and shoot accurately.

It's just my humble opinion based on my experiences that if you are going to size all of your cast boolits to match store bought plated/jacketed, then have your throats uniformly sized for that - but if you are using molds that drop from .452 - .454, and you want to use them unsized, then have your throats sized accordingly. I have no dog in this fight, but if I need a cylinder (throats) reamed, Doug would be the guy I would send it to and he could advise on the best course of action based on what you want to use.

A side note on chamber throat size and boolit diameter. I load and shoot both Remington 1858 and Colt clone Navy cap and ball revolvers with conversion cylinders. These are .36 caliber with .375 bore size and the cylinders have corresponding throat size. Normally, I load and shoot with a .375 "heeled" cast boolit in a 38 Colt Long casing. BUT - I can also use a .358 hollow base wadcutter or round nose and the shoot accurately as the soft lead expands into the .375 bore size. MY POINT? Yes it is a hollow base soft lead bullet, but is .358 going through and expanding in a .375 throat into the forcing cone and into a .375 bore - and it shoots accurately. If the .375 throats were .359 and then the boolit entered a .375 bore, accuracy would be out the window. A bit extreme in size dimensions, but the principle is the same.

Good luck with your new revolver and enjoy - I think you will be amazed at the change in accuracy when you get the throats reamed and uniform for the boolit/bullet size you plan to use.

[Outpost75]

I have been talking with him, and he says .4525 I’m just wanting second opion because I was told in past that when casting you always want to size .002 over what the caliber diam is for cast bullets
I’m just making sure this is correct

The Lyman old wive's tale is to size 0.002 over barrel barrel groove. Best practice is to ignore barrel groove diameter entirely and to size bullets to a sliding fit providing slight felt resistance in the cylinder throats. If Doug does your throats to .4525 factory .452 bullets will be a perfect fit and you can size your cast bullets appropriately to the same size.

The .454 size dies are needed only with older Colts or modern Italian clones having larger cylinder throats, which are typically .455".

[Piedmont]

It doesn't sound as if the original poster has measured his cylinder throats. He may not have the measuring equipment or know how for that (used to be me). So he is probably guessing that his throats vary also. Being a firm believer in if it ain't broke don't fix it, and knowing he already has a .452" and .454" die, I would cast two sets of bullets and size half each way. Then I would get at least three experimental loads and test everything on paper, from a rest, measuring groups and firing multiple groups with each combination.

Let the gun tell you what to do. It might do well with any combination above and then you could save your money for more primers and lead. If nothing is satisfactory, send off the cylinder for measuring and reaming.

[tacofrank]

A local gunsmith did both of my Vaqueros to .4525. All chambers were tighter than .4525. He also did the forcing cone to 11 degrees I think. Both are great shooters and shoot to point of aim and tight groups at twenty yards. love them.
Bad news is I shoot Cowboy Action and I never really had any complaints or seriously tested them for accuracy. My bad.
So I can't say they were improved enough to make a big difference. But they sure shoot great.
Several guys at my club said it was the thing to do and the price was reasonable so I had it done. Lol! But I remember the dimensions.
Makes me feel better about my guns.
TF

[Tar Heel]

Doug has done one of my revolvers and I have seen him work. Top notch. Period.

[Steve E]

Doug did my (large frame) Blackhawk cylinder and the throats were smoother, shooting my Blackhawk with the same load that I tested before he did the work there was an improvement with the groups. Well worth having it done.

Steve.......

[Outpost75]

Trying to ream cylinder throats with a chucking reamer, etc. is futile because you cannot match the factory roller-burnishex surface finish.

Doug guy's Sunned hone produces throats which are uniform, truly round and with superior surface finish approximating 8 micro inch RMS (root mean square).

My Rugers done by him group like rifles at 100 yards with my best loads.

[Thumbcocker]

Have you checked the throats? Ruger had come a long way on the uniformity of their throats.

[DougGuy]

Have you checked the throats? Ruger had come a long way on the uniformity of their throats.

The medium framed production is a great deal improved over the original large framed guns, I will give Ruger credit for that. The majority of medium frame 45 cylinders will pass a .451" pin and only some will pass a .452" pin. Some, not all of these cylinders still suffer from inconsistent throats, albeit not as bad as the large frame guns.

None that I have come across will pass a .4525" pin and this is a necessary measurement for shooting .452" boolits for 3 reasons. First off, a .452" boolit wil be hard to fit in a .452" throat, you may have to force ammo to chamber. It doesn't leave any room for even the slightest bit of eccentricity, and it doesn't leave any room for a boolit that might grow .0003" or more after sizing while it age hardens. This is why I recommend sizing throats .0005" to .001" greater than boolit diameter. You *need* that wiggle room, it just works.

[Larry Gibson]

Two of my three most accurate revolvers are Rugers; an original run Single Six in 32 H&R and a Bisley 41 Magnum. The third is a Colt Anaconda. All three have cylinder throats (pinned) that match exactly the groove diameter of the barrels [.312, .410 & .429]. Years ago, when I had a Power Custom PPC revolver built they matched the barrel groove diameter to the cylinder throat diameter [.357].

I had use of a very solidly mounted Ransom Rest and did considerable testing of different sized cast bullets in several different cartridges and revolvers. I found, with revolvers having cylinder throats larger than groove diameter best accuracy was with bullets sized .001 - .002 over groove IF they then fit the throats, or the throats were larger. However, with throats .003 or larger than groove diameter I never found any bullets more accurate that were sized to the throats.

This applied to lubed cast bullets as it is now known that lubed cast bullets, riding a layer of lube will be .003 - .003 under groove diameter on muzzle exit. The swaging down of a bullet .003 - .005 larger than groove dimeter + the additional swaging in the bore does not make for the best accuracy. PC and HT coated bullets are different and do not swage additionally down in the bore.

Interestingly, the most accurate ammunition [1 -1.5" twelve shot groups at 50 yards from the Ransom Rest] in my PPC revolver was Federal, Winchester and Remington 38 SPL Match WCs. Pulling the bullets of those back then reveled the bullets to be .355 - .356 in diameter. Best I ever got from my cast WCs was 1.5 - 2" twelve shot groups.

I would suggest to the OP he shoot a known accurate load with the bullets sized .452, of at least 12 shot groups at 25 yards but preferably 50 yards from a solid position/rest. That will give him a solid basis of comparison after having the throats honed, if he wants that done. Then, after the honing, shoot the same accuracy test with the same known accurate load at the same distance. That should show him the improvement.

[gpidaho]

Doug has honed four different Ruger revolver cylinders and throated a Ruger 45ACP barrel for me. All show improvement, the 44-40 old model Vaquero with the 44mag barrel (thanks for that Ruger) now accepts cast bullets without problems. This was a major frustration when the throats were .427 and the barrel was .432. Gp

[scattershot]

Just send it to Doug. He knows what he is talking about, and does beautiful work.

[siamese4570]

Doug is your guy for this. One other thing you need to watch is thread choke where the barrel screws into the frame. DougGuy did the cylinder on my ruger Bisley 45 colt but it was still leading. I slugged the barrel and found a tight spot at this part of the barrel. So the Bullet was leavin the cylinder and then getting swaged down at this tight spot and then skidded on the rifling past this spot, resulting in leading. The fix was fire lapping the barrel. Gun shoots great now.
siamese4570

[Alstep]

Doug has done several guns for me. I happened to be in his area, called ahead, and he was very accommodating. Invited me in and did the job right on the spot. Can't get any better service than that!