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Charlie Two Tracks
01-25-2011, 12:43 AM
I wanted to get some feed back about this load.
Mihec 359-640 mold sized to .359
Now here are the two boolits and loads.
.359 boolit 14.3 BHN 160 grains
13 grains of ACC. #9
OAL 1.59
or
.359 boolit 20.9 BHN (Monotype&WW) 155 grains
13 grains of ACC. #9
OAL 1.59
I got this load from Lymans #4 manual. I was wondering if there will be much difference in the two loads. One is softer but heavier and one is harder but lighter. Short of Quickload, I don't know if there is a way to see what will happen ahead of time. I live 20 miles from the nearest range and they charge $14.00 per hr. Maybe the only way to find out is to load the two and see what happens. I am going to shoot this in a Ruger GP-100 6" barrel. Let me know if I am over thinking all of this stuff. I forgot. Carnuba Red for the lube.

versifier
01-25-2011, 02:42 AM
...Maybe the only way to find out is to load the two and see what happens.....

That's about it.
Even with Quickload you can't predict much as there are too many factors involved that aren't taken into account. It doesn't do a bit of good to go by what happens in someone else's gun, even if it's the same model as yours. Every gun is different.

Have you slugged barrel, forcing cone, and cylinder throats, or are you just assuming groove diameter and going by trial and error?

If the bullets are undersized (and at .359 they may well be) the softer one should give you better accuracy as it will obturate to the grooves more completely. If so, watch when you shoot the harder bullet for leading in the breech end.

Charlie Two Tracks
01-25-2011, 11:16 AM
I have slugged my barrel and checked for forcing cone restrictions. The cylinder throats are at .357. The revolver shoots these boolits with 7 grains of Unique quite well. I am just trying a different powder. I wished I could just go out the back door and pop a few off and then adjust (or not) the load. Just me whinning. I hate paying to shoot. I've always shot out at my brothers farm but he sold it this winter. Oh well. Thanks for the reply.

Guesser
01-26-2011, 05:34 PM
Interesting discussion. I'm having trouble getting a S&W 65-1 to shoot cast bullets well. The chamber throats measure .357 and when I load and shoot cast bullets, even a 358156 gas checked and sized.358, the throats lead so bad that accuracy falls apart after about 35-40 rounds. I use these same bullets and loads in Colt Trooper 357's and Mark III 357's and Ruger BH and Sec. Sixes with no problem at all. The 65-1 even leads with 38 Special loads using these same bullets. I've tried commercial hard cast and my molds varying the alloys and the S&W leads badly, no leading in forcing cone or bore, just the chamber throats. I'm beginning to think it is S&W Stainless Steel and not design or tolerances. Had a 66-5 that did the same, it went to market, didn't like it anyway and the leading pushed it over the side. I'm thinking of opening the mouths to .358 or even .359. Any suggestions or opinion?

versifier
01-26-2011, 08:48 PM
Charlie,
The only way to know what powder it likes is to ask your revolver's opinion at the range. It sucks to have to pay that much. I have one free place to shoot, a 40mi round trip, so all I'm out is gas money. My club is a 90mi round trip, and costs $35 per year. I may not renew this year, I haven't decided yet.

Guesser,
Many production revolvers need their throats opened up to shoot cast. It is a common procedure and quite simple for a competent gunsmith to do. Many have throat variances of .002 or .003 within the same cylinder. Definitely have it done. Open them to .360 and slug your forcing cone to see if it needs it, too.

You will never get positive results when your cast bullets are larger than your throats and/or FC, though you will never notice a problem with jacketed bullets. You are also fighting a losing battle as long as you hang onto the myth that harder cast bullets work better in handguns. They do not, except in very special circumstances, none of which apply to revolvers except the supermags (.454, .480, etc.). The softer he alloy, the better the obturation to the barrel grooves, the better the accuracy, and the better the expansion in living tissue. When the throat or FC is undersized, the pressure behind it has to force the now smaller bullet to obturate to the barrel. If the alloy is too hard, it won't and all it does is cause leading. There is no "springback" in lead as there is in brass and steel - when the bullet is reduced in diameter, it stays that way unless it is soft enough for the propellant gasses to force it into the grooves. That is still not an ideal situation - far from it - but it is still better than what happens with a hardcast bullet.

Guesser
01-27-2011, 02:07 AM
I know about hard versus soft. I cast my bullets for 32, 38, and 45 of 50/50 pb/ww and it works well. I cast my 357 bullets of air cooled ww, it works well in every 357 magnum I've ever owned except those two S&W stainless revolvers. I want to keep the 65-1 because it handles the same as my 10-6. Its just the stainless cylinder thats giving me fits.

runfiverun
01-27-2011, 08:42 PM
i'm betting they are rough, collecting lead along the way.
i'd try a polish of the cylinder throats first.
flitz and a bore mop.

or the old shoot some hot jacketed stuff through there.
or some paper patched.
or some grit bedded stuff like those polishing kits they sell for rifles.
you can make your own with clover lapping compound and some cast boolits.

Guesser
01-29-2011, 09:11 PM
The gun is 35 years old and I suspect a police trade in, so I'm sure it has had its share of factory jacketed thru it. I'm working up to a polish job and see if it helps. I like the gun, but it will go to market if it doesn't match up with all the others for clean shooting. Its not worth a hassle with leading when all my loads work well in all the others.