Bullet Sizing Issues?

[Olon]

I have a Ruger super Blackhawk which recently I decided to look down into with my borescope. A nasty leading disaster awaited me, particularly around the beginning of the barrel.

I drove a soft lead ball from muzzle to breach (not sure if that's the right way to do it), and my groove diameter is .429". I will say that it felt tighter at the muzzle than it did at the breach end. A .430" bullet (what I've been using) drops through all 6 chambers with a slight push. The push so light that I could get it to drop though by knocking the cylinder in my palm to encourage it vs pushing.

These are 240 gn. SNS casting bullets which have a BHN of 16-17. I load them with 14 grains of blue dot which I'd consider a moderate level load, though it's possible that the leading is from my trail boss loads I've used with these same bullets.

I've read that hardness isn't really THAT big of a deal, especially compared to sizing and lube. While there was a bit of leading in the rifling the whole length, the fact that it's concentrated near the beginning of the barrel leads me to believe that the lube is adequate. The bullet measuring .001" over groove diameter seems right (I think?).

I must be missing something. Any advice?

 

[Anchorite]

Your Ruger sounds like it’s fine. You might do well to go .431 on your next batch of cast bullets, just to see if the leading eases. Nothing wrong with .430 you’re shooting now, but it does sound like your cylinder throats might be right at the edge of .430.

You can run a cylinder of jacketed and I bet it will clean right up.

 

[Olon]

Your Ruger sounds like it’s fine. You might do well to go .431 on your next batch of cast bullets, just to see if the leading eases. Nothing wrong with .430 you’re shooting now, but it does sound like your cylinder throats might be right at the edge of .430 which is also fine at the end of the day.

You can run a cylinder of jacketed and I bet it will clean right up.

Thanks a lot

Of course I notice this right after loading up a big batch but I'll keep an eye on it. Maybe it's just an accumulation from when I was even more of a rookie and had been known to occasionally shave a bullet here and there when seating

 

[Olon]

Gore warning:

 

[AJC1]

Gore warning:

View attachment 1240778

You need to get it completely clean or it will accumulate fast. It's one of those increases rapidly things...

 

[243winxb]

Extra hard bullet alloys will make barrel look like yours. My 200 round test showed no change in accuracy, but looked same.

Apply Lee Liquid Alox to bullets, before loading.

Shoot 1 round of all ready loaded ammo. Then 1 round of new batch with Lee Liquid Alox coating over current lube.

Report back.

Only the target knows. Photo of S&W 645, from muzzle.

 

[Anchorite]

It’s all about fit. Hardness or softness of the bullet is not nearly as critical as the fit to the cylinder throats and that relationship to bore.

Rugers are notorious about varying sizes of throats.

I think of you go .431 or even .432, you’ll see any lead deposits diminish. That lead is very likely from gas blowing by your bullet because it’s not sealing your bore when it’s fired.
Try some jacketed bullets too. It’s a fun way to clean lead from your bore.

 

[243winxb]

S&W M29-2 cylinder throats. 432" 25 yards. Barrel groove .4295"

 

[243winxb]

Doing your own testing, only way to know.

 

[Olon]

Extra hard bullet alloys will make barrel look like yours. My 200 round test showed no change in accuracy, but looked same.

Apply Lee Liquid Alox to bullets, before loading.

Shoot 1 round of all ready loaded ammo. Then 1 round of new batch with Lee Liquid Alox coating over current lube.

Report back.

Only the target knows. Photo of S&W 645, from muzzle.

Yeah, I don't think the targets are telling me there's much of a problem; at least not in front of the firing pin. I'll use a rest next time I go out

I will get some alox and see if that helps with the rounds I have loaded, then try a small batch of .431 bullets as well as some H110 loads with these to see if I'm just not driving them hard enough

 

[FROGO207]

Get some real copper chore boy scrubbers and wind a peice or two on a bore brush. That'll remove any lead in short order. A lowher BHN bullet and a flat based bullet will seal better. Or get a size larger bullet as mentioned above. The alox will help some but not a lot if the bullet is hard and you are gas cutting the sidewall. It needs to coat the whole side/base of the bullet so painting it on finished rounds will not help much.

 

[Olon]

Get some real copper chore boy scrubbers and wind a peice or two on a bore brush. That'll remove any lead in short order. A lowher BHN bullet and a flat based bullet will seal better. Or get a size larger bullet as mentioned above. The alox will help some but not a lot if the bullet is hard and you are gas cutting the sidewall. It needs to coat the whole side/base of the bullet so painting it on finished rounds will not help much.

That's how I've gone about cleaning it so far to great effect

 

[GeoDudeFlorida]

I drove a soft lead ball from muzzle to breach (not sure if that's the right way to do it), and my groove diameter is .429". I will say that it felt tighter at the muzzle than it did at the breach end.

Sounds like a case of Ruger’s famous frame constriction. A slight tight spot at the forcing cone where the barrel is screwed into the frame. The bullet gets swaged at the forcing cone and then gas etches the bullet.

That can be fixed but it isn’t cheap or easy. I’ve annoyed one or a few gun counter sales guys using pins and a gauge to check for that before making a purchase.

 

[.38 Special]

Probably a good idea to buy some pin gauges and actually measure the throats. I've come to believe the pushing bullets through throats is the sort of kinda-sorta measurement that leads us to believe that we've eliminated a problem when we may not have.

Beyond that, I think @GeoDudeFlorida probably has it right. Especially in .45 and .44, Blackhawks usually have a bore constriction that harms accuracy and causes leading. I would thoroughly clean the gun, and then slowly push an oversized, lubricated, pure lead slug down the bore. Nine times out of ten, a big bore Blackhawk will allow the slug to glide smoothly down right until the last inch or so, and then require an extra nudge to get it through the lede. If that ends up being the case, then no amount of fiddling with diameter, hardness, or lubrication will really solve the problem.

<edit> A key point: if you're happy with your accuracy, then you don't have a problem. Simply scrape out the lead after each outing and stop using your borescope!

 

[bullseye308]

Powder coating those bullets could add the needed diameter they are lacking and stop the leading.

 

[Olon]

Nine times out of ten, a big bore Blackhawk will allow the slug to glide smoothly down right until the last inch or so, and then require an extra nudge to get it through the lede

Thing is, opposite was the case. Assuming you mean push from muzzle to breech, anyway. The part where the barrel attached to the frame is looser than the rest.

 

[GeoDudeFlorida]

Thing is, opposite was the case. Assuming you mean push from muzzle to breech, anyway. The part where the barrel attached to the frame is looser than the rest.

That’s good!
Give it a good cleaning and check your bullets. A beveled base in plain lead is not the best thing for getting a good seal.

 

[Show Me]

Gore warning:

View attachment 1240778

Don't fret. Wrap some bronze wool around a smaller bronze brush. Cleanest right up. A spray of oily stuff on the wool helps. Then continue experiments

 

[Olon]

After I get through these bullets I'm definitely going to be moving away from bevel base

Now that components are more available I'm more inclined to experiment

Thank you guys for the advice. I'm headed to the range after work today to perform a benchmark test

 

[mdi]

For my 44 Magnums (5) I have always sized my bullets to the same diameter as the cylinder throats. Hopefully this will be .002"+ groove diameter. I have found an alloy of around 15 BHN to work quite well (perhaps obturating a bit after thread choke/bore irregularities). My SBH had a variation of .002" between throats so I reamed throats out to .4315". Hand reaming is simple, easy and with normal care accurate . Sized bullets to .431"-.432" depending on bullet design, and very little/no leading...

 

[LV Gun]

I see you are using one of my favorite powders in 44 magnum , Blue Dot. I have used a lot of BD in 357 magnum, 44 magnum and 454 Casull I would still be using it if it was available. The one thing I started doing is using Lee Liquid Alox on my lead bullets at the suggestion of winxb243 when I was having leading issues it will literally stop leading and even seems to clean out any that is in there.
. I just leave the lube in them that is in the groove and put the LLA right over it. I let them dry 24 hours and give them a dusting of ground mica powder before loading it eliminates any tackiness.
Your bullets are hard enough I use 15 BNH and with LLA on them you will be fine I use .430 bullets in my two 44 magnums I tried going to a .431 and had a very tight fit into the cylinder my cylinders pin gage at .430. Both of the barrels slug at .429 .

 

[Olon]

Control test from my loaded ammo. Will post a pic of the barrel after I clean the carbon out of it to record and share

Next round will be same thing but taking care to provide plenty of flare before seating as not to shave the bullet

Then liquid alox lubed bullets

Next with .431 bullets, probably with beveled base just to be consistent but I'm not sure.

 

[doubleh]

Yes, copper strands of a Choreboy scrub pad around a bronze brush will make short work of lead buildup in your barrel. Powder coating the bullets I cast has done away with any leading for me although I no longer shoot max loads in any handgun unless I use jacketed bullets. Sizing them is also easier, faster, and not nearly as messy now. I switched to Lee sizers and put away my old RCBS Lubrisizer.

 

[Pat Riot]

When ever you are in the market to buy new bullets I recommend you give Bear Creek Supply bullets a try. They are moly coated bullets. I have never had leading issues using their bullets. From .38 Special to .45-70 and no issues.
They’re definitely old school - you have to call to order, but their prices are very reasonable and they get your order out fast.
Also, if you require a special diameter they may be able to help.
I have no affiliation with BCS except as a very satisfied customer for over 25 years.

Official Website | United States | Bear Creek Supply

Bear Creek Supply Bullets. A Lead bullet manufacturer. Modern and obsolete bullets. Moly coated cast and swaged bullets. Since 1991

www.bearcreeksupplybullets.com

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