1st timer needs sage counsel...

[Laguna Freak]

I was directed to this site from some fine folks over at accurateshooter.

I hope to get some well informed and experienced opinions regarding cast boolit sizing and BHN for use in my 20 year old SS Taurus Raging Bull Model 444 w/6.5" barrel - factory muzzle porting. I am preparing to load commercially available 270gr to 290gr WFN, Round FN, or SWC bullets for hog killing and bear defense (including griz).

I have slugged the bore and measured the slugs(2) and, to best of my ability with micrometer, measured cylinder throats.
Throats = 0.4275" to 0.428"
Grooves (5) = 0.431"
Bore = 0.424"
*I measured slugs by rotating them in the calipers of my micrometer. So measurements reflect minimum and maximum range measured.
*I have experienced leading in and just beyond the forcing cone when shooting 0.429" to 0.430" jacketed FP and jacketed HP bullets.
*I have ordered rental of a 0.431" throat reamer and pilots.
*I have developed a minimally educated opinion with zero experience that for the applications above, I should be shooting 0.432" BHN in the 15 to 18 range. However due to ported muzzle, I have become convinced I need GC's. It seems the commercially available bullets in this weight range with GC are generally in the 20+ BHN range or 11-13 BHN. Regarding alloys, it seems they are difficult for me to identify and I am concerned about bullet shatter resistance.

I am having difficulty finding commercially available options with GC in the BHN 15 to 18 range and 270 to 290 grain range.

Where am I getting off track for my intended application against hogs and bears?

Thanks in advance for sharing your knowledge and experience.

[Der Gebirgsjager]

Welcome to the Castboolits Forum, Laguna Freak. All the questions that you have asked can no doubt be answered by those more expert than I. My opinion is that you probably should ream your cylinder throats to .431-.432. I see that you've ordered the equipment but--there is a member here, Doug Guy, who specializes in these ream jobs, and those who have used him praise his rates and work highly. Now we're out of the cylinder and into the bore. A groove diameter of .431 should work well with your cast bullets if sized to .433. Otherwise, if shooting factory loaded or handloaded JHPs of .429 you're likely still all right. Back momentarily to the cast bullets, if you have the cylinder throats reamed and you're shooting a harder alloy (I used straight wheel weights) then you probably won't need gas checks unless you're shooting very warm loads. If the leading is happening just past the forcing cone, then I can understand it with your bullets being squeezed down through the cylinder throats as they presently exist. It wouldn't hurt to ream the barrel forcing cone as well, to match the new cylinder throat sizes and bore diameter. Glad to have you as a new Forum member.

[Laguna Freak]

Thank you Der Gebirgsjager.

I’m assuming the minimal response to this thread indicates I am on the right track and am at least not “wrong-headed”.

Here is another question; Does anyone know / have experience with gas expansion chamber ported muzzles and plain base boolits? Ie; is the ported muzzle gas cutting of PB boolits, documented by Fryxell and others, mitigated by the gas expansion chamber?

I think I would likely get excellent performance from a commercially available 96-2-2 285gr SWC PB if it will not suffer performance hindering gas cutting at the muzzle ports.

[JonB_in_Glencoe]

My S&W X-frame 4" 500 came with two muzzle inserts, each with different porting (supposedly one for jacketed and one for cast), both of these have an expansion chamber.

I can't really answer your question about your gun, but I can say that I got a good amount of lead fouling in ports, whether I was shooting plain base or GC'd boolits. I didn't get lead fouling in the rifling, and I never really thought about the exact reason for port fouling, but figured it was just part of shooting that high pressure round. I never noticed any issue with accuracy between jacketed and cast boolits of either flavor, but I only shot at 50 feet. Anyway, I had a insert made with no porting to solve my problem...but now the gun has lots more muzzle flip.

[Laguna Freak]

Jon B,

Can you tell me what the average BHN of your cast boolits was in the above, approximately how many cast boolit rounds were shot before you assessed the fouling as "a good amount" and what average percentage of the ports' and expansion chamber's area were fouled at that same point?

Also, how did your boolits fit the throat and groove diameter relationship?

On a scale of 1 to 10, with 1 being easiest, how would you rate the difficulty in removing the lead fouling?

[mdi]

You mentioned measuring throats with your micrometer. Are you measuring a slug driven through the throats? Calipers, because of the jaw shape will not give an accurate measurement, often smaller (accurate measurements with a caliper type tool would need knife edge jaws, no flats). I've slugged cylinder throats, used pin/plug gauges and expanding ball gauges for accurate small ID measurements. The groove diameter of the barrel must be smaller than the throat diameter so with a .431" groove diameter, throats should be a minimum of .431" and .432" or larger. I think I would measure a few more barrel slugs and since you have a reamer coming proceede as planned.

I have been shooting lead bullets in my 5, 44 Magnums for about 25 years and since I cast, most of my bullets are 11-12 BHN and none harder than 15 (Lyman #2). No need for anything harder. I have cast an loaded bullets ranging from 123 gr balls to 310 gr ingots and have never needed anything harder. Since you are using commercial cast bullets and they seem to believe "harder is better" you will have little control there, but you should find a caster that offers different diameters per bullet/caliber as bullet to gun fit is #1. Since you are going to ream your throats to .431" I would suggest you make sure your bullets are the same diameter; .431".

You mention you were getting leading with .429"-.430" jacketed bullets. Typo?

[Laguna Freak]

You mentioned measuring throats with your micrometer. Are you measuring a slug driven through the throats? Calipers, because of the jaw shape will not give an accurate measurement, often smaller (accurate measurements with a caliper type tool would need knife edge jaws, no flats). I've slugged cylinder throats, used pin/plug gauges and expanding ball gauges for accurate small ID measurements. The groove diameter of the barrel must be smaller than the throat diameter so with a .431" groove diameter, throats should be a minimum of .431" and .432" or larger. I think I would measure a few more barrel slugs and since you have a reamer coming proceede as planned.

I have been shooting lead bullets in my 5, 44 Magnums for about 25 years and since I cast, most of my bullets are 11-12 BHN and none harder than 15 (Lyman #2). No need for anything harder. I have cast an loaded bullets ranging from 123 gr balls to 310 gr ingots and have never needed anything harder. Since you are using commercial cast bullets and they seem to believe "harder is better" you will have little control there, but you should find a caster that offers different diameters per bullet/caliber as bullet to gun fit is #1. Since you are going to ream your throats to .431" I would suggest you make sure your bullets are the same diameter; .431".

You mention you were getting leading with .429"-.430" jacketed bullets. Typo?


mdi,

Yes sir! I slugged the bore, actually 2 slugs, 2 times. Slug dimensions and measurement method are listed above in my OP.

No sir. Not a typo re; leading in the forcing cone and first portion of grooves. The jacketed FP and HP bullets I have been shooting are as old or older than the revolver and have a fair amount of exposed lead. I did not figure out why leading was happening until I began studying up on cast boolits and the importance of the bullet : throat : groove relationship.

Do you think that with a properly fitted bullet to gun, plain base bullet in the 11 to 16 BHN range, that I am not likely to encounter traditional leading or leading of the ports and gas expansion chamber as discussed above?

I have found a 180 grain GC (95.75%Pb, 3%Sb, 1%Sn, 0.25%As) and 185 grain PB (96-2-2) bullet that are advertised to be in the 11 to 13 BHN range out of the mold. I can get them sized to 0.431 or 0.432. I'm thinking they will age harden to 14 to 16 BHN. I got this from Fryxell.

Thank you for sharing!

[mdi]

In my Ruger SBH, S&W 629 and Dan Wesson 44H, I get minimal to no leading with my 11-12 BHN alloy even to upper loads of Unique, 2400 and WC820. But I measured the throats in each and sized bullets to the same diameter. I shoot a lot of 429421 SWCs, plain based, lubed with either Carnauba Red or my home made Speed Green. I haven't suffered from my initial case of "Magnumitis" in several years but many loads are around 1,000-1,100 fps...

[Laguna Freak]

In my Ruger SBH, S&W 629 and Dan Wesson 44H, I get minimal to no leading with my 11-12 BHN alloy even to upper loads of Unique, 2400 and WC820. But I measured the throats in each and sized bullets to the same diameter. I shoot a lot of 429421 SWCs, plain based, lubed with either Carnauba Red or my home made Speed Green. I haven't suffered from my initial case of "Magnumitis" in several years but many loads are around 1,000-1,100 fps...

Thank you for the encouragement.

I pulled the trigger on some 285 grain Keith style SWC PB sized 0.432” in the 12 BHN range. I’m sure they’ll harden a couple points over a month or 2. They’re longish too but my cylinder is 1.76”+ long. So I’ve got room for them. I hope their caliber doesn’t grow more than .001” by the time I get ‘em shot. Of course the way commercial is these days, I’ll be lucky to have these boolits in my hands by Thanksgiving

After I ream cylinder throats, I’ll polish the last .0015” out. I hope...

[Land Owner]

Some casual cast boolit thinking:

Historical evidence indicates, in the lead days (BHN ~6) before alloys of wheel weights, Old Timers learned that "slow" (a relative term) and heavy for caliber cast boolits were suitable Buffalo "medicine" and practically wiped them from the face of the Earth. Those guns were their only "equalizers" against all things with cloven hoof, teeth, claw, and bad men, at least and until the inventions of modern gun powder and swaged and jacketed bullets.

The U.S. Civil War was fought with slow cast boolits and musket balls of soft lead to include this story of bravery and survival:
http://castboolits.gunloads.com/showthread.php?145416-History-Question-Lead-Casting-And-The-Civil-War&p=1612595&viewfull=1#post1612595

I doubt bears today are tougher than bears of yesteryear, though I wouldn't begin to challenge that theory. Control of your weapon in the face of rising fear in placing rounds where they will do the job is the right stuff. Slow and heavy for caliber have been tested and found to be sufficient.

[JonB_in_Glencoe]

LF,
The GC'd boolits were cast with air cooled 94-3-3 (also contains about a 1/4% CU) Bhn is 14.
The plain based was cast with an alloy 80% COWW and 20% Monotype, Bhn about 18.
I'd notice lead in all ports within a couple cylinders worth of ammo.
It was enough lead to notice during cleaning.
I haven't "slugged" Barrel or throats...but I did push a .501 boolit through each throat, there was slight friction making be believe they were the correct size.
It was very easy to remove lead fouling with a bamboo skewer...let's call it a 1.