New Vaquero slugged too tight?

[HawkCreek]

I bought a Ruger New Vaquero off gunbroker not long ago. Havent shot it yet but I figured the down time would be a great time to load up some ammo. I've never slugged a barrel before but after reading a bunch of opinions (here and other places) I tried today. I had some new fishing weights (very soft so I assume pure lead). The tightest point in my NV barrel is .444 this seems pretty tight for a .45 to me. Cylinder throats are pretty uniform at .451 (my apologies I wrote .458 and didnt catch my typo) with the forcing cone a bit tighter than that. Should I be worried about the barrel measuring .444 or did I pull a bone head new guy screw up?
No burrs or anything obviously visually wrong that I can see. Gun appeared new with little or no use when I got it. I didnt drop the lead after I slugged the barrel or otherwise deform it. I'm using Hornady digital calipers, my Starretts are in storage or I'd compare with those in case my calipers are simply off.

Help!

[DougGuy]

I think the calipers are throwing off your measurements. Sounds like you are measuring bore diameter, which is the land-to-land distance, you would be measuring the grooves in the slug after it dropped out. Measuring the fat part of the slug would be measuring the groove diameter in the barrel which Ruger has held right at .451" now for decades. Your bore measurement should be closer to .4425"

Cylinder throats in these new medium framed models are right at .451" - .4515" not anywhere near .458"

[HawkCreek]

I think the calipers are throwing off your measurements. Sounds like you are measuring bore diameter, which is the land-to-land distance, you would be measuring the grooves in the slug after it dropped out. Measuring the fat part of the slug would be measuring the groove diameter in the barrel which Ruger has held right at .451" now for decades. Your bore measurement should be closer to .4425"

Cylinder throats in these new medium framed models are right at .451" - .4515" not anywhere near .458"
Sorry, I meant to type .451 for the cylinder throats. Not sure how I missed that.
I'm measuring the widest point of the slug not the narrowest. Is that not correct?

[megasupermagnum]

Try this. Only start a weight into the muzzle. Some use short sections of dowel through the frame end to push the slug back out the muzzle. I've had luck using a short section of brass rod, say 3/8", and rocking the revolver to slide hammer the slug back out. If the muzzle end measures say .451", and the slug you pushed all the way through is truly .444", you have a serious bore constriction that needs fixing. That would be about the worst I have heard of. Usually .002" is plenty bad.

[HawkCreek]

Try this. Only start a weight into the muzzle. Some use short sections of dowel through the frame end to push the slug back out the muzzle. I've had luck using a short section of brass rod, say 3/8", and rocking the revolver to slide hammer the slug back out. If the muzzle end measures say .451", and the slug you pushed all the way through is truly .444", you have a serious bore constriction that needs fixing. That would be about the worst I have heard of. Usually .002" is plenty bad.

Muzzle is the tightest point. It took a bit to get the lead started, once the ring of excess was removed it fairly sailed down the barrel and only needed a light coaxing to get past the forcing cone.

[megasupermagnum]

Something is amiss. If your muzzle groove diameter was .444", then your rifling would be nearly missing. I have to wonder if you didn't get the slug cocked in the bore, causing a misreading.

[Skipper]

Are you trying to measure an odd number of lands and grooves?

[tazman]

Just for grins, try pushing the slug from the barrel through the cylinder throats. If your measurements are accurate, it should just drop through easily. If it is a snug fit, the measurement is off.

[HawkCreek]

Just for grins, try pushing the slug from the barrel through the cylinder throats. If your measurements are accurate, it should just drop through easily. If it is a snug fit, the measurement is off.

I did that before I even measured it. Drops right through the throats of each chamber.

6 lands and 6 grooves by my count.

It's possible I somehow got the slug started and then canted it I suppose. But I was surprised at how faint the rifling marks seem to be. They are there and identifiable but not deep at all.

[tazman]

Well, you shouldn't have issues with leading as the groove diameter is less than the cylinder throats and presumably smaller than whatever you will size your boolits.
With very thin rifling, you may have an issue with the boolits shearing and not getting a good grip on the rifling.
No way to know without trying it and see.

[megasupermagnum]

I did that before I even measured it. Drops right through the throats of each chamber.

6 lands and 6 grooves by my count.

It's possible I somehow got the slug started and then canted it I suppose. But I was surprised at how faint the rifling marks seem to be. They are there and identifiable but not deep at all.

One other thing you can try is with your calipers in the muzzle, see approximately how deep the rifling is. If the rifling is only .001" deep, well there it is. It wouldn't be unsafe, and you could shoot. Just as easily you could send it to Ruger, and they would fix it for free.

[tazman]

Some of the early 1911 45ACP barrels had thin, shallow rifling and required really hard alloy for boolits to be accurate in them.
I had a similar issue with a couple of 9mm barrels. They worked fine with jacketed but not with cast. The barrels got replaced and they work fine now.
If the rifling is too shallow to properly grip the boolits, I would do as MSM suggested and sent it back to Ruger with a description of the issue.

[HawkCreek]

I'm having trouble measuring the muzzle (not enough hands) but the grooves in the slug are .437 to .440
I'm going to try again before I send it off. I was going to order some bullets to try, sheesh all I wanted was to know what size to order. I've got an old model Vaquero and a Winchester 92 that I was going to check.
Any tips before I try again? I'm wondering more and more if I didnt somehow get the slug canted at the muzzle which threw everything off.

[Tripplebeards]

I’d have to go back into my load books but if I remember all my throats were .451 as well and my barrel Slugged about .0005 smaller(.4505). I ran my .451 slug through my barrel after I sized it through my throats. I found at .451 a sized boolit could easily be pushed through all my throats with very little pressure with the use of my finger or a pencil. When I slugged my .451 sized boolit through my barrel I had plenty of deep grooves in my boolit (slug) from the barrel lands/grooves. I was paranoid that my boolits would not be oversized enough vs my bore diameter to shoot accurately and I would have leading. All I can tell you is my vaquero shoots in the same hole at 15 yards and I can hit shotgun shells consistently at 25 yards freehand with it and absolutely no leading issues. I loaded my boolits long to the point they are almost touching the forcing cone. I’m using 5.2 grains of trail boss, the lee 255 grain mold, 50/50 alloy with 2%pewter, and PC. Fun times! Dougguy walked me through the process. My new vaquero is one accurate pistol! It shot to the left till I adjusted my finger placement on the trigger. Now I’m dead center. I have to lower my front blade about half way down into the rear sight to be right on the money.

[megasupermagnum]

I'm having trouble measuring the muzzle (honor enough hands) but the grooves in the slug are .437 to .440
I'm going to try again before I send it off. I was going to order some bullets to try, sheesh all I wanted was to know what size to order. I've got an old model Vaquero and a Winchester 92 that I was going to check.
Any tips before I try again? I'm wondering more and more if I didnt somehow get the slug canted at the muzzle which threw everything off.

You can certainly try it as is. It may even shoot well. If you have any jacketed bullets at .451", try those in the throats. If those are a slip fit, buy .451" cast bullets. Being as .450" bullets may be tough to find, .451" may be your only option anyway.

[HawkCreek]

All I've got around is a partial box of American Eagle 225 grain. No bullet pullers handy. Most of my recording stuff is in storage.
I'll try to measure it again but if I get similar results I'll probably see if Ruger will replace my barrel. I bought this gun to shoot cast, specifically the 270 RCBS design. Looks like .451 is the smallest I can get from Montna Bullet Works. Part of me wants to try it out but it also seems like I would be toeing the unsafe side of the line.

[Gohon]

Something is amiss. My New Vaquero 45 Colt I bought about three years ago slugged .4515 cyl throats, .450 groove and .442 bore diameter. .452 casts shoot just fine for me. You said the slug sailed down the barrel after the excess ring was removed. You sure the fishing weight lead was really as soft as you thought?

[Tripplebeards]

I would take it to a smith to slug it again for a second opinion. I don’t think your barrel measurement is correct. I normally run a few slugs through my barrels and take the average measurement between them. I use a cheap harbor freight micrometer so it’s not the most accurate measurement devise but gets the job done.

[megasupermagnum]

All I've got around is a partial box of American Eagle 225 grain. No bullet pullers handy. Most of my recording stuff is in storage.
I'll try to measure it again but if I get similar results I'll probably see if Ruger will replace my barrel. I bought this gun to shoot cast, specifically the 270 RCBS design. Looks like .451 is the smallest I can get from Montna Bullet Works. Part of me wants to try it out but it also seems like I would be toeing the unsafe side of the line.

Personally I question the measurement, but even if it is correct, and Ruger messed up on the rifling, it should be safe to shoot.

[tazman]

All I've got around is a partial box of American Eagle 225 grain. No bullet pullers handy. Most of my recording stuff is in storage.
I'll try to measure it again but if I get similar results I'll probably see if Ruger will replace my barrel. I bought this gun to shoot cast, specifically the 270 RCBS design. Looks like .451 is the smallest I can get from Montna Bullet Works. Part of me wants to try it out but it also seems like I would be toeing the unsafe side of the line.

You will not blow up the gun using standard loads and .451 bullets or boolits. Remember, the factory did proof test the gun with loads that should be beyond anything you will ever run through it. Shoot it and find out what it does.
If it won't work right, then send it back for correction. .451 down to .444 is only 7 thousandths after all. I don't consider that enough to be a dangerous situation.

[Valley-Shooter]

We need a little bit more information.

1. Did you clean the barrel before you started? The whole bore brush and patches thing. No copper or lead is in the barrel.
2. Did lubricate the bore with oil?
3. Is the slug big enough? Squeeze it in a vise to make it bigger if you have to.
4. Where is your micrometer? That what you need to measure with.

I would just start over.

Sent from my Pixel 4 XL using Tapatalk

[HawkCreek]

We need a little bit more information.

1. Did you clean the barrel before you started? The whole bore brush and patches thing. No copper or lead is in the barrel.
2. Did lubricate the bore with oil?
3. Is the slug big enough? Squeeze it in a vise to make it bigger if you have to.
4. Where is your micrometer? That what you need to measure with.

I would just start over.

Sent from my Pixel 4 XL using Tapatalk

Bore was clean and lightly oiled.
Slug was considerably oversized, it left a sizable ring when it was fully past the crown.
I dont own a micrometer, calipers is all I've got to measure with.

I want to check it again I'm just not sure how I screwed up the first time. Dont want to keep repeating it wrong.

[mdi]

Since I wasn't there when you slugged and measured the barrel and throats, I can't really offer any "expert info" on a possible faux pas. But I would suggest trying at least 4 or 5 more slugs and use a 1" micrometer...

[DougGuy]

Ruger has been making 45 caliber barrels right at .451" for decades. They are VERY consistent in the groove measurement. Since your slug slid past the barrel/frame juncture without stopping, this tells me there is no thread choke to worry about and that's a good thing.

Most would opt for .452" boolits in a 45 caliber gun, this is almost a universal size for that caliber. I'd say over 90% of handloaders use .452" boolits in 45 caliber. Maybe one out of 1500 45 caliber cylinders that come through my shop go out .4515" and this is at the shooter's request. The rest get honed to .4525" which is pretty standard for use with .452" boolits. You can also use .451" boolits without issue if they are not super hard alloy.

I would simply have the cylinder honed to .4525" use .452" boolits and dismiss all this slugging stuff. It will work GREAT. Slugging a Ruger barrel is almost a waste of time anymore, unless you have a weird issue and can't troubleshoot it. In this thread, the slugging process seems to have created WAY more problems than it is worth.

As long as the boolit is delivered to the forcing cone at least groove diameter or larger, you are good to go. My suggestion for this caliber is always .001" to .002" over groove diameter, it just works.

I also do not suggest using hard cast in a Ruger, the rifling in these barrels is such that an alloy of 50/50+2% and soft lube takes to the barrel like a duck to water. I have not cleaned a revolver barrel in years. There is no leading at all, just a dark residue of burned powder and lube left behind which acts as "seasoning" for follow up shots. Probably the worst boolits you can use are the commercial magma cast which are roughly BHN22 with that hard crayon lube. Guaranteed leading even if all dimensions are correct.