Ruger oversize groove diameter

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Catpop

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Ruger is MY first choice in single action revolvers. That said----
Why is it the 2 Ruger blackhawks I end up with, new or used, will not shoot commercially available lead bootlits.
I seem to be getting close with my .357 at .361, but now its almost to large to chamber. Throats at .360 now.
Ive tried my new 44 mag with .431 and its still leading. Throat .431 from factory.Not done much testing there yet as I'm concentrating on the 357 right now (have been for a year)
Shouldn't a new barrel be made to shoot .358 and .430 without leading issues? Or is it just me?
 
Lube problem is my guess.

I don't see 3 barrels , all having the same problem.

Bullet diameters of .358" and .430" has worked in many firearms for me. 50/50 lube.

Try some Lee liquid alox.
 
More info needed.

Have you slugged the barrels? How did you measure the throats? Loads used? Lead used? Lube used? Bullets used?

Commercial cast bullets are normally BHN 15-18 which is way too hard.

If fact, if you want, send me your address and I'll send you out some bullets to try in your .357.
 
Throats originally .358 measured with pin gage
Reamed to .360 measured with pin gage
Loads 4.5 and 5.0 universal
Missouri .358 measuring .3585 to .359 severe leading
Acww, .358 lee mold severe leading alox lube and RCBS lube and every other one I've tried
Wcww .361 unsized boolits from noe mold given to me by redrider2011 to try shows most promise at no leading, but not finished testing yet. Do not have .360 sizer yet- working on that
Do not have an exact groove slug yet-working on that.
Land diameter .347 plus pin gage, but don't have a .348 to try yet.
.347 will pass all the way thru barrel
This is same pistol I posted "ruger thread choke" about earlier- lots of info there

Reason for post was just wondering do others have this same leading problem with Rugers?
 
Ruger is MY first choice in single action revolvers. That said----
Why is it the 2 Ruger blackhawks I end up with, new or used, will not shoot commercially available lead bootlits.
I seem to be getting close with my .357 at .361, but now its almost to large to chamber. Throats at .360 now.
Ive tried my new 44 mag with .431 and its still leading. Throat .431 from factory.Not done much testing there yet as I'm concentrating on the 357 right now (have been for a year)
Shouldn't a new barrel be made to shoot .358 and .430 without leading issues? Or is it just me?

All leading went away when I switched to coated bullets, along with the lube goo/smoke and I'll never go back to traditional lubed cast bullets.
jmo
:D
 
I run three Redhawks and a couple of GP-100's. I size .358, 410, 430-431, and 452 and have no issues with leading unless I try to run alloy too soft for the loads or anything above around 16-18 BHN.

Most of my loads run on the hotter side for cast loads as I use them for hunting. I actually blended the alloy up to handle the velocities I might hit with each caliber respectively. I use two different ones, the first will do wonderful up to right at 1100fps and then smears terribly, the second works up to around 1600 as as far as I have pushed it in my 357's and 41.

As for the issues your having, This is what my 41 looked like with only 4 rounds through it using the first alloy I mentioned. The first couple of inches,
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Pretty much the rest of the 7/5"
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Same alloy as the 41, but in my 45 Colt, and after putting over a hundred plus rounds through it,
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Now that said, I ran the second alloy mentioned cast in some 180gr HP's through the 41 up to 1600fps and it looked pretty much unfired except for some powder residue. Same with the 357's using a healthy dose of AA-9 and some 160gr HP's up into the 1350fps range. These were all lubed using Carnuba Red and sized as stated above. In my 44 however if I try to use a hard alloy it just pukes out lead like an extrusion machine. I have to keep things at or under the above mentioned BHN with it. The GP-s will do the same thing, but I believe on them it is more due to not being able to run the bullets hard enough. Even so I found what DOES work through them and I'm sticking with it.

I also run the Lee 452-300RF cast with air cooled WW, sized to .452" and lubed with two coats of Alox, once before sizing and once after, through my Raging Bull at 1550fps with no issues.

I'm not saying I'm an expert at this but something is giving you fits and it is sounding like you might have the thread squeeze issue in at least one. I have only heard of it being a real pain in the RH's, but I might be mistaken. I would for sure get them slugged to find out, and if that is the case it isn't a huge deal to remedy it, just a bit time consuming. The cylinder thing is an easy fix, and I have heard of more having that problem than anything else. If your choked down in the beginning your never going to get a clean shooting barrel with cast. They just don't squeeze down then get fatter again once the pressure get around them.

The biggest thing with cast is finding what DOES work and that is a big balancing act of alloy verses pressure. You might WANT to push a bullet to X velocity with Y alloy but sometimes you don't get what you want. I foudn that out several times while working up my two blends and it's also why I HAVE two blends I use. I could use straight WW, for 99% of what I shoot and do if I am casting a solid. I just happen to like shooting the HP designs and worked through trial and error to get what I needed. Trust me I had plenty of barrel cleaning time before I got to what worked in them all.
 
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Throats originally .358 measured with pin gage
Reamed to .360 measured with pin gage
Reaming was not needed, unless the barrels groove diameter is .360"
Or is it just me?
Could be, if making the wrong adjustments.
Throats originally .358 measured with pin gage
Reamed to .360 measured with pin gage
Reaming was not needed, unless the barrels groove diameter is .360"

Know the barrels groove diameter first. Then size to that diameter. (Old Lyman info). This means 99% of the time, standard sized cast bullet diameters will work. 358, 430. IMO.

Real leading, is a loss of accuracy. If accuracy goes , you have a problem.
 
Will post exact groove dia next week when i get chance to play again. First preliminary slug last year was over .3595, but I needed a better micrometer term to be sure. Never got back to it.
Thanks for all the great help!
 
I know I am giving away my age, but whatever happened to gas checks? Any time you try to push lead bullets too fast you will get leading; unless you use gas checks or very hard bullets.

Jim
 
ruger single action revolvers don't have the best forcing cones. some are really bad. if yours is bad, no "reaming" will help. stick a bullet into the forcing cone end of the barrel and see if the cone is cut deep enough.

my 44 special blackhawk has a shallow forcing cone and does not like plain lead bullets, jacketed and gas checked lead bullets work fine.

murf
 
ruger single action revolvers don't have the best forcing cones. some are really bad. if yours is bad, no "reaming" will help. stick a bullet into the forcing cone end of the barrel and see if the cone is cut deep enough.

my 44 special blackhawk has a shallow forcing cone and does not like plain lead bullets, jacketed and gas checked lead bullets work fine.

murf
That and barrel restriction from the threads, luckily both the thread restriction and forcing cone can be greatly improved via lapping.
:D
 
Yeap, I've already got 70 fire-laps through it and as soon as I get a .348 pin gage, I'll know if I'm close on the thread choke which it does have. Again, a .347 pin gage will slide all the way through.
Funny thing is unsized .361+ diameter boolits don't lead. They also don't always chamber!!!! Not sure about .360 as I do not have that sizer yet!
I don't think 4.5 universal is very hot.
 
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Getting close to answer on leading. I am currently testing .360 lswc with 5.0 gr. universal. The cartridges fit the chambers fine and the barrel leading has been greatly reduced if not totally eliminated. And this is with liquid alox for a lube.
I will post final results soon.
 
Howdy

Until you slug the barrel, you are poking around in the dark.

You don't need a micrometer to slug the barrel, a regular dial caliper is fine.

If you need instructions on how to slug a barrel, speak up.
 
With the .360 throats I think you are going to have problems with any lead bullet .359 or smaller. Have you tried powder coated bullets? They should get rid of the leading but accuracy is still going to be a problem if smaller than .360.
 
Will let you know final results after next range session. I do know:

1. .358 and .359 lead severely in as little as 50 rounds, both factory lead and hand cast boolits.
-indicating a groove diameter greater than .359

2. .361- .362 have totally eliminated leading issues, but cause chambering issues.
-indicating a groove diameter less than or equal to .362

3. .361-.362 do not lead even with just 1 thin coat of lee liquid alox while the. 358 and .359 lead with both hard and liquid lubes.
-indicating lube is not the issue with leading.
-this quest was not about pc or lubes which I'm sure tend to mask the basic problem of boolit fit.
4. .3605+/- cylinder throats not an issue
-indicated by fact I .361-.362 have been sucessfully fired with no leading

By taking the backwards approach long hard road to this quest I have thoroughly enjoyed it and learned a lot.

I thank all for their input and help. Again I'll post final solution for my 1973 blackhawk's problem which was a faultly sized barrel from the factory that would not shoot plain .358 lead boolits without leading.

Ruger will also get all these results along with the proof when I finish.
 
if your barrel slug is .3595" groove diameter and your throats are reamed out to .360", anything less than .360" diameter lead bullets will lead your gun. .360" and greater diameter will work wonderfully in your gun. colt 38 caliber da revolvers were all (most all) made with .354/.355" groove diameter barrels. .358" diameter lead bullets work fine in colt revolvers because the bullet fits the cylinder throat and not the barrel grooves.

just don't run any more .358" diameter lead bullets in that gun.

luck,

murf
 
Murf,
I ran both factory and my cast boolits since the 80s in my bh with every combination of lube, powder, primer, etc you can think of with no solution to the leading. I even quit using unique and cast bullets for 20 years due to the headache involved with deleading the barrel.
It wasnt until I joined the highroad that I became enlightened with all kinds of great knowledge about cast boolits, leading and the like.
I never really had any extra time to stop and really try to figure the problem out in my earlier years. I just took the easy road and started reloading jacketed only.
I've slowed down a bit now and take it one quest at a time. This quest has been really fun as I am now seeing the light at the end of the tunnel.
I think I've learned enough in 200k+ rounds over 45 years to know .358 or .359 do not and will not work in my bh.
Thanks to all you old wise ones that have helped me along with this quest!
 
Murf,
I ran both factory and my cast boolits since the 80s in my bh with every combination of lube, powder, primer, etc you can think of with no solution to the leading. I even quit using unique and cast bullets for 20 years due to the headache involved with deleading the barrel.
It wasnt until I joined the highroad that I became enlightened with all kinds of great knowledge about cast boolits, leading and the like.
I never really had any extra time to stop and really try to figure the problem out in my earlier years. I just took the easy road and started reloading jacketed only.
I've slowed down a bit now and take it one quest at a time. This quest has been really fun as I am now seeing the light at the end of the tunnel.
I think I've learned enough in 200k+ rounds over 45 years to know .358 or .359 do not and will not work in my bh.
Thanks to all you old wise ones that have helped me along with this quest!
we give our opinion to try and help, not just you, but everyone else that may have a similar problem. i don't know if my suggestion will eliminate your leading, but it should. won't know till the bullet goes down the barrel. glad you got this figured out and relayed the solution to us all.

murf
 
There is a reason I don't own more Ruger revolvers, they over size cylinder throats.
I was interested in a GP-100 44spl. the one I looked at was not appealing, I had a Hornady .431" 240 gr JHP with me and the bullet fell through all cylinders with room to spare.
My S&W 696 cylinder throats measure .429" and .430" cast works well. It's difficult to find a cast bullet that won't lead my Redhawk.
 
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Could this be why Ruger is said to take hotter loads? because they have over bored throats that reduce pressure?
 
There is a reason I don't own more Ruger revolvers, they over size cylinder throats.
I was interested in a GP-100 44spl. the one I looked at was not appealing, I had a Hornady .431" 240 gr JHP with me and the bullet fell through all cylinders with room to spare.
My S&W 696 cylinder throats measure .429" and .430" cast works well. It's difficult to find a cast bullet that won't lead my Redhawk.
I also found my new 2017 .44 mag sbh to have .431 throats, but contrarily found my 1973 .357 bh to have .358 throats (measured with pin gage)
 
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