Single Six question

[contender]

"What about the Ruger Single Ten's? Anyone know if those use the larger magnum bore?"

Re-read my comment; "All Ruger Single-Six models, built after serial number 150000 have the larger bore sized for .22 mag. None built since then have the smaller 22 LR bore. "

[bigbore5]

It's a theory I have that seems to work. Not so relevant to jacketed bullets or tumble lubes, but..

Of course we size our revolver bullets to the throats, they travel into the throats and are compressed. Entering the rifling it will be sized to two diameters, bore and groove. Of course groove diameter is the larger when the bullet reaches the outer diameter of the rifling. But what about the bore?

The bore diameter is the grooves left in the fired bullet. I look at how deep these grooves in the bullet are in relation to the depth of the grease groove in the bullet. If they go all the way to the bottom of the lube groove or deeper, that bullet seems to be more tending to lead the edge of the rifling. I've shot many thousands of them. So did Keith, Smith, Jones, and many others. They like deeper lube grooves too.

If the lube groove diameter is larger than bore diameter, the rifling completely displaces the lube to the sides, causing the rifling to ride nothing but the lead without the layer of lube displaced on to it by the compression of the base.

If the lube groove is smaller than the diameter of the bore, then a thin layer of lube will remain between the rifling and the bullet in the bottom of the groove. As the base of the bullet is driven forwards under the pressure of firing it will compress the lube groove and pressurize the lube, cushioning leading edge of the rifling and providing a better gas seal.

Or maybe my theory is just a figment of my imagination that has seemed to work well.

[rjtodd]

Thanks for that detailed explanation. I follow your reasoning and can see the merit of the deeper grooves. Even the Barnes solid copper bullets seem to use some of this same thinking to reduce copper fouling. I appreciate the explanation and will definitely ponder the idea fo r a while.

Best,

Randy

[bradshaw]

Sept 23, 2024 9:11:25 GMT -5 contender said:

All Ruger Single-Six models, built after serial number 150000 have the larger bore sized for .22 mag. None built since then have the smaller 22 LR bore.

*****

Tyrone.... thank you for clarifying a dimensional weakness which has plagued the Single-Six most of its life.

Doubt it would hurt the gun or shooter at all to correctly dimension all .22 Long Rifle revolvers for minimum variance, with smooth forcing cone and perfect chamber-to-bore alignment. I believe we’d find excellent accuracy from both .22 Long Rifle and .22 Winchester Magnum Rimfire. It’s an experiment I would have liked to ne involved in. Don’t know whether Ruger ever conducted such an experiment.

The concept of obturation----plastic deformation of bullet to fill a generous groove diameter----traces to the Minie Ball. The Mini Ball ia purposely made undersized facilitate loading down a bore fowled by black powder. The Minie has a deep hollow base. Combustion expands the bullet skirt into rifling grooves to seal the bore and give the bullet traction to spin. It’s my humble theory that the Minie principle was then applied to lead bullets in general to rationalize a oversize groove diameter or undersize bullet.

The OBTURATION THEORY was extended to include jacketed bullets. Neither a hard cast bullet nor a jacketed bullet easily subscribe to obturation. It takes a lot more pressure to bulge a jacketed or hard lead bullet into the grooves. I’ve listened to obturation theory at the manufacturing level, and taken the opportunity to assert my FORCING CONE argument.

When applied to a solid bullet, part of obturation theory holds that cross-sectional BORE AREA of grooves & lands combined is more important to accuracy----and to pressure regulation----than groove diameter. In other words, that the lands make up for an oversize groove. I submit the Firing Line demonstrates otherwise.
David Bradshaw

[bigbore5]

One would figure that the people who make guns would shoot them enough to know what works or else be smart enough to get advice from someone who has

[contender]

"One would figure that the people who make guns would shoot them enough to know what works or else be smart enough to get advice from someone who has"

When Bill was alive,, they did a lot of that. BUT,, marketing was also a part of the business. Remember,,, any business is there to make money. The guns are the route to that. And the demand from the public to be able to shoot both the .22 LR & the .22 magnum from the same gun was high enough to where adjusting the bore diameter was an easy marketing decision. Besides,, back then,, many people didn't look at a handgun as a seriously accurate firearm. And in my opinion,, Winchester screwed up by making the .22 magnum slightly different to where that was the issue.

The market is driven by volume sales. Money is the bottom line. Folks who want "more" are forced to pay a bit extra for the more detailed work. Bill was out to make money & saw the concept of a convertible like that as a win-win marketing thing.
Same thing with the .357/.9mm convertible Blackhawks.

[ridenshoot]

Sept 24, 2024 20:50:41 GMT -5 bigbore5 said:

It's a theory I have that seems to work. Not so relevant to jacketed bullets or tumble lubes, but..

Of course we size our revolver bullets to the throats, they travel into the throats and are compressed. Entering the rifling it will be sized to two diameters, bore and groove. Of course groove diameter is the larger when the bullet reaches the outer diameter of the rifling. But what about the bore?

The bore diameter is the grooves left in the fired bullet. I look at how deep these grooves in the bullet are in relation to the depth of the grease groove in the bullet. If they go all the way to the bottom of the lube groove or deeper, that bullet seems to be more tending to lead the edge of the rifling. I've shot many thousands of them. So did Keith, Smith, Jones, and many others. They like deeper lube grooves too.

If the lube groove diameter is larger than bore diameter, the rifling completely displaces the lube to the sides, causing the rifling to ride nothing but the lead without the layer of lube displaced on to it by the compression of the base.

If the lube groove is smaller than the diameter of the bore, then a thin layer of lube will remain between the rifling and the bullet in the bottom of the groove. As the base of the bullet is driven forwards under the pressure of firing it will compress the lube groove and pressurize the lube, cushioning leading edge of the rifling and providing a better gas seal.

Or maybe my theory is just a figment of my imagination that has seemed to work well.

The following is a link to Chapter 5 of Glen E. Fryxell's "From Ingot to Target: A Cast Bullet Guide For Handgunners".  This talks about bullet lubrication and has a section specifically dealing with "Lube Pumping Mechanisms".  It's really interesting  in case you have never had an opportunity to read it.


www.lasc.us/Fryxell_Book_Chapter_5_Lubrication.htm

[bigbore5]

I've read it and agree for the most part. I just don't think he looks at the lube groove depth having a role beyond just capacity

[axman]

May those tools like Pacos and such that bump up diameter some to be of help?

[contender]

Yes,, quite often,, the Paco Accurizer can help with accuracy.

[squawberryman]

That article is definitely paying attention to you "hobby".

[x101airborne]

A thought from the crayon eating department here:
I get the premise that litigation drives certain decisions and that is why the S6's all have the .224 groove diameter for the 22 Magnum but does squeezing that bullet down .002" really increase pressure all that much? Like shooting 7.62x39 bullets in a 308 Winchester (I know this is a much larger bore / groove situation so proportionally is less dramatic) we squeeze bullets down all the time. Is the decision to use the .224" barrels purely a CYA tactic? I am not educated enough to answer my own question.

[bradshaw]

Sept 26, 2024 6:39:01 GMT -5 x101airborne said:

A thought from the crayon eating department here:
I get the premise that litigation drives certain decisions and that is why the S6's all have the .224 groove diameter for the 22 Magnum but does squeezing that bullet down .002" really increase pressure all that much? Like shooting 7.62x39 bullets in a 308 Winchester (I know this is a much larger bore / groove situation so proportionally is less dramatic) we squeeze bullets down all the time. Is the decision to use the .224" barrels purely a CYA tactic? I am not educated enough to answer my own question.

*****

Trey.... no need to eat crayons, your questions are completely valid.
My suspicion: Ruger settled on .22 WMR groove diameter for all Single-Six .22’s:
1) simplicity during assemble, with lower cost than offering two distinct groove diameters, as contender reports. And the more direct motive....
2) SAAMI specifications, which member manufacturers have strong incentive to adhere to. Sales-wise, Ruger hit a grand slam with his Single-Six Convertible. While a relatively few owners really shoot their Single-Six with mags, millions more rounds of .22 Long Rifle are consumed. Ruger did a sales experiment and dropped the mag cylinder: shooters rebelled, even those who hardly or never shoot .22 WMR in their revolver insisted they want the option.

As to why Winchester added a couple thousandths to the magnum rimfire bullet, probably to prevent cramming into a .22 Long Rifle chamber.

Strength is not an issue with the Hell-for stout Single-Six, heat treated frame, etc. The experiment I would appreciate seeing: .22 LR groove-diameter barrel with carefully worked up forcing cone, sandbagged @ 100 yards with respective cylinders and cartridges.
David Bradshaw

[contender]

Once again,, David's info is also quite correct & enlightening.

And he's right,, the more "casual" shooters like the idea of a convertible gun, and the sales prove it. SERIOUS shooters want the gun to be as good as possible to do things MOST people won't try or even consider possible. Like David mentions, the proper grooved .22 & carefully worked forcing cone & shooting at 100 yds.

[bigbore5]

Dave's "experiment" is what I am looking to build.