help choosing revolver bullet diameter

[oley55]

I have a Ruger RH, 44mag, 7.5" barrel. after re-slugging too damn many times, I am reasonably confident in these measurements.

cylinder throats slugged at .4327-.4328".
barrel slugged .4300-.4301".

based forum information I have read, my bullets should be sized to the cylinder throat size and should pass through with light pressure.

looking at different sources, I found Beartooth sells .44 lead sized to: .429", .430", .4315", and .432". https://beartoothbullets.com/bulletselect/index.htm (https://beartoothbullets.com/bulletselect/index.htm)

based on throat diameters, .432" is the closest I can get, but they will very likely fall through the throats.

Am I slipping into the custom mold and sizing die world?
If so, how much difference in diameter from cylinder throat to barrel can I safely shoot?
And finally is this particular RH basically a jacketed bullet only firearm?

[RED333]

Well you are on a web site about "casting" your own boolits.
I have a SBH, I cast and size to .432 and it fits mine just fine.

[dubber123]

.432" will probably work fine. It's not too hard to get molds and sizers of .433" either, if you so choose. Some of my older Lymans and Ideals cast right around .433", and if you get one that is at least .432", it's relatively easy to lap a mold slightly larger.

I'd try .432" first, and I bet you'll be happy. The measurements you give are not uncommon, my brothers Blackhawk has similar dimensions, and shoots very well with the appropriately sized boolits.

[tazman]

If you use the .432 sized boolit, depending upon the alloy and lube used, there is only a slight possibility of leading. Probably will not be an issue.
The press fit to cylinder throats is a suggestion for best practice and is not engraved in stone. Many people use smaller than throat size boolits successfully with no issues at all.
As far as diameter difference to barrel, you can quite safely use .432 boolits in a .430 barrel.

[DougGuy]

Yep, I use .432" in my SBH, it had uneven throats, two were .4325" two more were .4315" and the other two were .4305" and the only "fix" for one like that, is to size all of them to the largest throat and get them all even and consistent, then size the boolit to a light drag fit in the throats. Irregardless of the final diameter of the throats, having them all the same, and sizing to a snug fit is about as perfect as you can get with a revolver cylinder.

[Bigslug]

I would order the mold to drop for between .433" to .434" (NOE has several that are probably there already) with whatever alloy you plan to use, and run them in a .432" sizer. You'll probably get a little springback from your metal, and end up slightly over .432". Working in thousandths is fine, but I would not be laying awake nights contemplating tenths of thousandths. Assuming you end up at something like .4322", you'd have .0002" to .0003" of "slop" on either side of the boolit. I'm no machinist, but I think that's well inside happy slip fit numbers.

[oley55]

thanks guys I found this article at: http://www.lasc.us/Fryxell_Book_Chapter_7_Leading.htm , just a few minutes ago.

Leading caused by the gun. There are certain critical dimensions of the gun that can cause leading if they are "out of spec". Again, starting with the rear of the gun and moving forward, the first of these would be the cylinder throats. If the throats are grossly oversized (.004" larger than groove diameter) then if the cast bullet is soft enough it can "bump up" when fired, becoming oversized for entry into the forcing cone, creating lead deposits when it gets swaged back down at this point. With harder bullets, oversized throats do not usually cause a leading problem (although accuracy may suffer due to poor alignment during the cylinder gap transition).

so it looks like my .0028 oversize throats are indeed not grossly oversized and all is well.

[prs]

It is difficult to measure the cylinder throat diameters without pin gauges. Choose .432" and see if there are any problems before buying in bulk.

prs

[oley55]

It is difficult to measure the cylinder throat diameters without pin gauges. Choose .432" and see if there are any problems before buying in bulk.

prs

I have also pin gauged. .432" (.4319") will pass thru all six cylinders. 3 of those are slightly tight but they still go thru without force. the .433 (.4329") will not even start in any of the cylinders. note: the ( ) number is my micrometer measurement of the pins. Just gotta double check those Chinese pin gauges. They are minus gauges and the .0001" is dead-on for minus pin gauges. Although I have found some not so accurate, hence the reason for checking.

Frankly I was thinking slugging would be more accurate, but now that I think about it, spring back is likely giving me the .0007-.0008 bump.

so it looks like a modest purchase of .432s for a trial run.

thanks all for the help and advice.

[454PB]

You are cetainly on the right track and have obviously done your homework. In my opinion.......worrying about fourth decimal place measurements is a waste of time, especially when it's a boolit as big as a .44.

My 35 year old Redhawk has been fed .430" to .432" boolits by the tens of thousands and does fine with all.

[oley55]

You are cetainly on the right track and have obviously done your homework. In my opinion.......worrying about fourth decimal place measurements is a waste of time, especially when it's a boolit as big as a .44.

My 35 year old Redhawk has been fed .430" to .432" boolits by the tens of thousands and does fine with all.

Mine is also 31 or 32 years old, but have almost always used jacketed. A recent purchase of lead bullets resulted in HEAVY leading. Bought them before I had done any homework. They were 240gr, RNFP, .430", Hi-Tek coated bullets from SNS casting. Fortunately my similarly aged Dan Wesson is perfectly sized for .430".

[44man]

Mine has .4324" throats and shoots fine from .431" to .432". No leading and I use 22 BHN boolits.
I have shot thousands of .430" boolits with no problems.

[trapper9260]

I have at first in my Redhawk size to .429 before I was learning more form here and other places and then I went to .430 and I see alot better for how the gun shoots.So i stick with .430 now on all my 44 mags.

[MtGun44]

Try .431, but .432 should work better. No harder than air cooled wheelweight alloy to start,
use a "known good" lube like NRA 50-50 or LBT soft blue before going off and adventuring
with other lubes.

Bill