Chamber vs bullet size

[Sarsaparilla Kid]

I bought a package deal that consisted of a Pietta .44 cal revolver, 200 Hornady .457 round balls, and a Lee conical bullet mold sized at .452. I measured the chambers and came up with .445 inches. Seems like much over .451 or .454 round ball would be tough to load. Should I just buy all available round ball sizes and try them out for accuracy and loading difficulty and find a happy medium? Is that conical bullet size going to be about right, or should it be closer to the chamber measurement?

 

[Smokerr]

The chamber is going to squeeze the bullet down to whatever size it is.

I have been discussing that with another guy, its the barrel size that is going to determine things.

If the Chamber is enough smaller than the barrel, you would need to have the cylinder reamed to get accuracy. Otherwise it does not engage or fully engage the rifling and you have a semi musket.

I have tried conical bullets (JD type) and found them a lot worse than ball.

I need to do a full workup data wise, slug the barrel and measure the chambers and get it in a table.

 

[Sarsaparilla Kid]

Thanks...I'll check the bore and see what the delta is between the two and report back!

 

[Bad Karma]

I bought a package deal that consisted of a Pietta .44 cal revolver, 200 Hornady .457 round balls, and a Lee conical bullet mold sized at .452. I measured the chambers and came up with .445 inches. Seems like much over .451 or .454 round ball would be tough to load. Should I just buy all available round ball sizes and try them out for accuracy and loading difficulty and find a happy medium? Is that conical bullet size going to be about right, or should it be closer to the chamber measurement?

The chambers are probably undersized for the bore. Bore dimensions should be .450 or so with grooves at .454-.458”.
I hear this concern about loading difficulty and somehow I’m missing something, most of the time I load on the gun and many of mine are 5-6” barrels of I have never thought, “wow! That’s hard to load!” I use dead soft lead and yes, many of mine have been reamed to .454-.456 but even stock Uberti revolvers with .450 chambers are not difficult enough to raise any concerns.
Generally revolvers are most accurate if the throats are .001 or .002” over groove diameter but I have had pistols that showed very fine accuracy with .450/.456 chambers and groove measurements. The soft lead bullets or balls do expand into the bore under the pressure of a kick in the pants from a charge of blackpowder. I always shoot new guns a bunch before beginning any permanent mechanical alterations.

 

[rodwha]

I shoot .457” balls in my Pietta Remington. I did eventually get it reamed to 0.449” from 0.446”. My barrel has 0.453” grooves. My bullets drop at 0.454” and these aren’t stressful either

 

[Smokerr]

Doing a bit of dimensioning on my 47 Walker.

Barrel is .453.

But the cylinders have some taper so the size of your ball going into the barrel varies depending on how deep its set down in the cylinder.

.446 - .449 at the top.

5/8 on down its .438

 

[M. De Land]

The chamber is going to squeeze the bullet down to whatever size it is.

I have been discussing that with another guy, its the barrel size that is going to determine things.

If the Chamber is enough smaller than the barrel, you would need to have the cylinder reamed to get accuracy. Otherwise it does not engage or fully engage the rifling and you have a semi musket.

I have tried conical bullets (JD type) and found them a lot worse than ball.

I need to do a full workup data wise, slug the barrel and measure the chambers and get it in a table.

I think the reason most all percussion revolvers show up with undersized chamber mouths is because they are primarily set up for ball shooting rather than conicals. Most all will shoot balls more accurately than conicals in the factory configuration. If alignment is good and the chambers are reamed to groove diameter than the conicals can catch up to and some times exceed the balls accuracy.
Balls are not sensitive to seating alignment as they have a hemispherical base where as conicals are very sensitive to base square at seating to achieve accuracy. If the bullet hits the forcing cone cockeyed than it's shape is distorted and as it leaves the muzzle the uneven gas escapement from it's base amplifies the distorted bullets flight path.

 

[M. De Land]

Doing a bit of dimensioning on my 47 Walker.

Barrel is .453.

But the cylinders have some taper so the size of your ball going into the barrel varies depending on how deep its set down in the cylinder.

.446 - .449 at the top.

5/8 on down its .438

Uberti Walkers have seven lands and grooves which make it difficult to accurately measure groove diameter to achieve proper bullet diameter. It is usually safe to get as close a reading as one can and add .001-.002 to the diameter to make sure the grooves are sealed. One needs a Powely gauge or tri-mic to get an accurate read on the actual groove diameter.
I always lap my bores to level if I find tight spots in the bore diameter but not sure how well it shows up in pistol accuracy although am convinced it does improve target rifle accuracy from a harmonics prospective.

 

[M. De Land]

I shoot .457” balls in my Pietta Remington. I did eventually get it reamed to 0.449” from 0.446”. My barrel has 0.453” grooves. My bullets drop at 0.454” and these aren’t stressful either

 

[M. De Land]

One of the variables you will find when cross mic-ing your cast bullets is they will very often come from the mold and be out of round and need sized to make them so.
It is unusual to get a mold (even high dollar custom jobs of which I have quite a few) that will cast perfectly round balls/bullets without some lapping help. If one can get them within half a thousands that is really good. Most molds drop bullets several thousands out of round and the forcing cone in the barrel may be the only sizing die they get before headed down range .

 

[rodwha]

One of the variables you will find when cross mic-ing your cast bullets is they will very often come from the mold and be out of round and need sized to make them so.
It is unusual to get a mold (even high dollar custom jobs of which I have quite a few) that will cast perfectly round balls without some lapping help. If one can get them within half a thousands that is really good. Most molds drop bullets several thousands out of round and the forcing cone in the barrel may be the only sizing die they get before headed down range .

Interesting. I use Accurate Molds to make my designs and will again soon. When I made the current few designs I was under the mistaken understanding that the Ruger bullets needed to 0.456” wide so it’s what I had mine made at. There’s no need to be any more than 0.001” larger. I was considering having my next design drop at 0.454” but maybe I should instead have the mold designed for 0.455” as I have a 0.454” sizer. If the mold were to drop at 0.454” as designed, and are out of round, would the 0.454” sizer fix that swaging anything back into place?

I’m no pistolero, though I’m not bad once I’ve been shooting regularly, but I could use all the help I can get, especially as I’d like to be good enough to hunt with my Ruger as a primary, but I don’t think I’m good enough out to 25 yds yet as my 15 yd targets were giving me the group size I hold myself to, up to 4”. I’m getting 3-3.5” when I’m shooting, semi-weaver like. Most likely I’d hunt from a fixed position where I could use my knees or something.

 

[M. De Land]

Interesting. I use Accurate Molds to make my designs and will again soon. When I made the current few designs I was under the mistaken understanding that the Ruger bullets needed to 0.456” wide so it’s what I had mine made at. There’s no need to be any more than 0.001” larger. I was considering having my next design drop at 0.454” but maybe I should instead have the mold designed for 0.455” as I have a 0.454” sizer. If the mold were to drop at 0.454” as designed, and are out of round, would the 0.454” sizer fix that swaging anything back into place?

I’m no pistolero, though I’m not bad once I’ve been shooting regularly, but I could use all the help I can get, especially as I’d like to be good enough to hunt with my Ruger as a primary, but I don’t think I’m good enough out to 25 yds yet as my 15 yd targets were giving me the group size I hold myself to, up to 4”. I’m getting 3-3.5” when I’m shooting, semi-weaver like. Most likely I’d hunt from a fixed position where I could use my knees or something.

How about carrying cross stix with you while hunting both as a hiking staff and shooting support? This will greatly extend your accuracy potential at distance.
As to the molds, you can lap them to round using a bullet cast in them with shaft centered through the sprue plate. The shaft of course to be gripped in a drill press or even hand drill to turn the cast bullet made into a mold lap with lapping compound. In practice the bullet is charged with lap compound after the parting lines are filed off and the mold is held on a flat surface and slowly closed around the spinning lap which will bounce around a bit at first being out of round but will eventually settle down , even out and lap a round cavity. It is slow going and takes for ever to remove even .001.
At first the high spots in the lap are taking out the low spots in the mold and when it settles down it is evening out the cavity. The drive axial must of necessity be on center and perpendicular to the lap slug.
This is with mehanite ( fine grain cast iron and steel ) molds. I have not tried lapping out aluminum or brass molds so your on your own in lapping them although it would be worth a try in and old mold not needed for experimenting on.
As to bullet diameter I don't like going over .001 above measured barrel groove diameter after being lapped level.
I spent ten years competing in Midrange black powder cartridge competition ( 200 yards offhand, 300 sitting and 600 prone) which gives good prospective on cast bullet accuracy and ow it is achieved. We found that the more round one could cast the bullets without sizing them the better the accuracy.
Some folks could keep their bullet weight variance down to half a grain plus or minus a targeted weight in 500 plus grain bullets.
We all used volumetric powder measurement and drop tube charging.

 

[M. De Land]

Interesting. I use Accurate Molds to make my designs and will again soon. When I made the current few designs I was under the mistaken understanding that the Ruger bullets needed to 0.456” wide so it’s what I had mine made at. There’s no need to be any more than 0.001” larger. I was considering having my next design drop at 0.454” but maybe I should instead have the mold designed for 0.455” as I have a 0.454” sizer. If the mold were to drop at 0.454” as designed, and are out of round, would the 0.454” sizer fix that swaging anything back into place?

I’m no pistolero, though I’m not bad once I’ve been shooting regularly, but I could use all the help I can get, especially as I’d like to be good enough to hunt with my Ruger as a primary, but I don’t think I’m good enough out to 25 yds yet as my 15 yd targets were giving me the group size I hold myself to, up to 4”. I’m getting 3-3.5” when I’m shooting, semi-weaver like. Most likely I’d hunt from a fixed position where I could use my knees or something.

I've made quite a few molds over the years boring them in my lathe to suit a certain need encountered. I used to make them from scratch with mild steel , spure plate, air vents and all but finally wised up and started picking up small mold blocks at gun shows and simply boring them out to the bullet needed. Saves all the machine work of making them from bar stock. I typically pick them up for 5-10 bucks complete.
To soon old .............. to late smart I guess!
Most current is a paper patch design for a British SMLE I thought up, of all things ! The first experimental bullet for this project was key holing at 50 yards, still scratching my head on that failure but what an opportunity to learn something interesting ! First slug I ever made that key holed........... wonder why?
I made up one for another rifle just before that really demonstrates good accuracy.
Any thing applicable to rifle is equally adaptable to percussion hand guns and will be employed in the future.
So far the ACP bullet shown in the Walker thread works so well and is in the weight class I envisioned that I doubt I could improve on it.
My reasoning is that the original ball load worked great in them and was only something like 146 grains if memory serves and this bullet at 200 grains is much heavier. Also this weight/length will allow seating through the frame window already in the gun without having to alter it.
I've not shot any game with it so don't have any experience at how well it will kill but reason seems to point that if a much lighter ball could get the job done than a much heavier bullet should work well.
The other advantage is this heeled base design is tailor made for ram seating in the chamber mouths and the truncate-flat pointed nose makes centering in the ram nose equally efficient to get the base square to the bore.

 

[rodwha]

How about carrying cross stix with you while hunting both as a hiking staff and shooting support? This will greatly extend your accuracy potential at distance.
As to the molds, you can lap them to round using a bullet cast in them with shaft centered through the sprue plate. The shaft of course to be gripped in a drill press or even hand drill to turn the cast bullet made into a mold lap with lapping compound. In practice the bullet is charged with lap compound after the parting lines are filed off and the mold is held on a flat surface and slowly closed around the spinning lap which will bounce around a bit at first being out of round but will eventually settle down , even out and lap a round cavity. It is slow going and takes for ever to remove even .001.
At first the high spots in the lap are taking out the low spots in the mold and when it settles down it is evening out the cavity. The drive axial must of necessity be on center and perpendicular to the lap slug.
This is with mehanite ( fine grain cast iron and steel ) molds. I have not tried lapping out aluminum or brass molds so your on your own in lapping them although it would be worth a try in and old mold not needed for experimenting on.
As to bullet diameter I don't like going over .001 above measured barrel groove diameter after being lapped level.
I spent ten years competing in Midrange black powder cartridge competition ( 200 yards offhand, 300 sitting and 600 prone) which gives good prospective on cast bullet accuracy and ow it is achieved. We found that the more round one could cast the bullets without sizing them the better the accuracy.
Some folks could keep their bullet weight variance down to half a grain plus or minus a targeted weight in 500 plus grain bullets.
We all used volumetric powder measurement and drop tube charging.

I did find a very nice, fairly straight yucca “stick” that I took and cleaned up thinking it might well do this. The truth is I’m a poor stalker. I have untreated ADD and I eventually end up walking a bit too fast. I’ve been thinking I should try shortening my walk to sitting at the base of trees for a bit, maybe that will help me focus better.

The problem with Texas is nearly the whole damn state is owned, and these people tend to put blinds and expect you to stay in small areas, so the main lease I was invited to I’d only do this during lunch time when the boss generally always went back to camp, and it was just us. It’s not safe or respectful of others to stalk. Leases cost an arm, leg, and your firstborn so I’ve been considering out of state hunting such as New Mexico or maybe Arizona, somewhere that has open lands and inexpensive licenses.

Of course because of the way hunting is here I’ve not had much opportunity to practice stalking. My father taught me bits when I was a teen, but I lived with my anti gun mom, so lessons were few and far in between, not to mention long ago now. So I figured stalking from tree to tree might help me slow it down better.

 

[rodwha]

I've made quite a few molds over the years boring them in my lathe to suit a certain need encountered. I used to make them from scratch with mild steel , spure plate, air vents and all but finally wised up and started picking up small mold blocks at gun shows and simply boring them out to the bullet needed. Saves all the machine work of making them from bar stock. I typically pick them up for 5-10 bucks complete.
To soon old .............. to late smart I guess!
Most current is a paper patch design for a British SMLE I thought up, of all things ! The first experimental bullet for this project was key holing at 50 yards, still scratching my head on that failure but what an opportunity to learn something interesting ! First slug I ever made that key holed........... wonder why?
I made up one for another rifle just before that really demonstrates good accuracy.
Any thing applicable to rifle is equally adaptable to percussion hand guns and will be employed in the future.
So far the ACP bullet shown in the Walker thread works so well and is in the weight class I envisioned that I doubt I could improve on it.
My reasoning is that the original ball load worked great in them and was only something like 146 grains if memory serves and this bullet at 200 grains is much heavier. Also this weight/length will allow seating through the frame window already in the gun without having to alter it.
I've not shot any game with it so don't have any experience at how well it will kill but reason seems to point that if a much lighter ball could get the job done than a much heavier bullet should work well.
The other advantage is this heeled base design is tailor made for ram seating in the chamber mouths and the truncate-flat pointed nose makes centering in the ram nose equally efficient to get the base square to the bore.

Dang, that is clever just modifying molds in place of creating them.

I’m going to hafta look for that thread, I’m always curious about the projectiles people use, and what their experiences are.

I’m still stuck in wanting a very wide meplat, though I’ve contemplated reducing it a smidge, but if I did that I’d no longer be able to load the designs I currently have as I’d eventually use epoxy to make a ram face that won’t distort the noses upon loading. I hate my Pietta ram’s kiss it leaves.

Speaking of keyholing, I’m curious if those light and very short bullets I sent destabilized as you figured out past 50 yds IIRC.

 

[M. De Land]

Dang, that is clever just modifying molds in place of creating them.

I’m going to hafta look for that thread, I’m always curious about the projectiles people use, and what their experiences are.

I’m still stuck in wanting a very wide meplat, though I’ve contemplated reducing it a smidge, but if I did that I’d no longer be able to load the designs I currently have as I’d eventually use epoxy to make a ram face that won’t distort the noses upon loading. I hate my Pietta ram’s kiss it leaves.

Speaking of keyholing, I’m curious if those light and very short bullets I sent destabilized as you figured out past 50 yds IIRC.

I'm currently in the process of modifying the Uberti Walker with a new front blade, action shield , sear lift and loading lever catch an am about to head back to the range for more load development.
It may yet need a chamber reaming but will wait on that mod for a bit to see how and what load development reveals. The chambers are very uniform and alignment is good so it should be a real shooter as is.
I stashed the bullets you sent around here some where and if I can find them I'll test in the Walker along with my ACP bullet and some more ball loads.
I also picked up a Pietta 51 a year ago that is being modified a bit and yet to be fired so have quite a bit of load development and sight filing to do.
The 51 doesn't swallow caps into the action like the Walker so probably won't put a shield on it but it does need a sear lift to remove the trigger creep that is showing up as the gun breaks in.
Oh, by the way, the action shield I was testing on the Walker that I sweated on with force 44 silver solder did not hold so I made another an attached with a steel rivet secured with red lock tite into a .250 deep x.080 wide hole drilled into the top of the case hardened hammer. I'm quite sure that will hold and can avoid the cross cut notching purchase I never cared for of securing them to the hammer.
I also put a set of slix shot nipples on the gun and will test them against the factory nipples that seemed to work fine in the first range test.

 

[M. De Land]

Dang, that is clever just modifying molds in place of creating them.

I’m going to hafta look for that thread, I’m always curious about the projectiles people use, and what their experiences are.

I’m still stuck in wanting a very wide meplat, though I’ve contemplated reducing it a smidge, but if I did that I’d no longer be able to load the designs I currently have as I’d eventually use epoxy to make a ram face that won’t distort the noses upon loading. I hate my Pietta ram’s kiss it leaves.

Speaking of keyholing, I’m curious if those light and very short bullets I sent destabilized as you figured out past 50 yds IIRC.

The wide meplat makes sense in keeping the length down, the weight up and slamming into game like a broad axe. The trick I guess is to make it workable for ram seating in the gun and not deforming the nose in the process.
As to stability I'm not sure I fully understand how it occurs other than to start them out straight in a twist rate adequate to the length. I have one bullet I use that is just about a perfect cylinder like a wad cutter but is stable to a tested 200 yards. Wad cutters are seldom sable past 50 yards.
I think one might be better off not employing a grease groove at all so as to keep the weight up and length down but rather using a thin grease wad or cookie although that would cut down on powder volume in a ROA or Pietta but is no problem in the Walker's cavernous chambers.
A cookie for those who have not used one is a lube flat cylinder in leu of a felt wad usually used with a thin milk carton wad instead as a barrier between powder and bullet.

 

[Eutycus]

A post awhile back had some one say reamed a cylinder to .449.How was that number picked?

 

[rodwha]

A post awhile back had some one say reamed a cylinder to .449.How was that number picked?

It was all Fly felt comfortable taking it to he said. I can’t say whether or not it improved things, but I don’t see how it couldn’t. But it would improve even further if I can get it to or above groove diameter (0.4535”).

 

[nkbj]

With the Pietta .44's perhaps a practical improvement would be reaming them to a little larger diameter but only about a half inch or so deep. That way you could have the useful option of seating either spherical and cylindrical bullets appropriate to your groove diameter.