PB 357 mag mold

[Kirk Miller]

Long time lurker, small time poster. Please have patience.
Just about every question I've ever had about casting has been asked and answered here. So a heart felt thanks to everyone that makes this board such a great one.
This is the situation that I'm in. I cast round balls and maxi's 25 years ago for my muzzle loader but just started casting for my 357's and 30-30 in the last year.
So far in my GP100, the lyman 358665 under 5.5gr. unique has been very accurate. The problems start when the charge is increased to 6gr. Groups start to spread with each increase. Same with my mod. 66 with four in. bl. Now the strange thing is that after fireing several groups of 5.5gr. unique, I can then shoot four shots of the same boolit over 14gr. of 2400 and get {no kidding} 3/4in. groups. After four shots the groups will increase to five or more in. I should mention that all groups are shot at 23 yds.
This mold is supposed to be 158gr. but with my alloy of 50/50 pb/ww it drops at 167gr. I don't know if the bevel base is to be blamed, alloy is too soft, or if there is too much pressure. If I could, I'd blame it all on the bullet design but the same exact results occur with my two 358477 molds both of which are the older style with the round lube groove.
I'm using BAC lube and sizing to 358. I've tried sizing 359, 357. 360 and Hp38, tight group and HS6 in every combination I can think of and so far 358 and unique have worked the best.
So to make a long story even longer, in the opinion of those that have tried the many different molds, what in your collective opinion is the most accurate PB boolit other than round nose {358311} in the 357 mag. This to be used {hopefully} at both low and high velocity. High being in the 1200fps range.
Glen Fryxell in his articles, mentions the H&G 51, saeco 82 and a couple of others that I can't remember so, if anyone can shed some light on my questions I'd be very appreciative and gratefull.
Thanks
Kirk

[Kirk Miller]

I forgot to mention that I've got a 358429 sc mold that drops boolits at .362, .363 when cast of ww. When sized they smear the crimp groove pretty bad and group terrible with any thing I try. So, if anyone wants it, let me know.
Kirk

[HamGunner]

Sounds like you might need to sort your bullets out better by weight and or appearance. I also sort mine out by how they feel as I size them, easy in one pile and more difficult or larger bullet in another. It might be other factors, but sounds like you might be getting one flyer out of the bunch because it weighs more or less than the average.

I also have the 358477 and I get tack driving accuracy with 5.0 to 5.5 of Unique in either 38 Spec. or 357 cases.
I bought an old used 358429 sc and wanted to try some hot loads in 38 brass, but the thing throws an off round bullet that measures only .355 on the sides. I guess someone has messed with the thing and ruined the die. I'll have to see if I can adjust it somehow.
Perhaps you can adjust your alloy a bit to get yours to throw a smaller bullet.

[MtGun44]

Is the accuracy loss due to leading?

I have had excellent accy with the RCBS 150 SWC in several .357s. Some decent,
some horrible with the Lee 150 truncated cone BB, jury still out. Many good and
great groups with 358429, but almost always with hot loads in my limited experience.

You might give heat treating a try, it isn't real hard to do a small batch and see
if it helps. Too bad about the fat .358429 - put it on the selling section and
be sure to call it a FAT 358429, I'd bet there is somebody out there that has
been looking for one for 3 years or something.

Bill

[crabo]

Kirk, pm me and give me an address and I'll send you some H&G 51s. I've just started testing them for accuracy so I can't give you much info that way. I would need to cast some up this week, but I wouldn't mind.

Crabo

[45r]

The best PB mold I have is a Mtn Mold 180 secant that makes boolits that look like the saeco 180 grain TC #396.It shoots one inch at 25 yards in my model 27 with 7.2 grains unique.I tried the lyman and rcbs 150 grain swc PB and they couldn't do as well as the GC boolits in 156 grain lyman and the 162 grain rcbs so I sold them off.Long heavy boolits have done the best for me when it comes to PB in 357 mag.The saeco 180 FN #353 would probably do well.

[Kirk Miller]

HamGunner
I always have sorted my boolits by weight{+/- .5gr.} so I don't think thats its weight, but I never thought about sorting by feel. Something else to try. Thanks
Mtgun44
There seems to be no leading and I can go back to the original 5.5gr. unique load and accuracy returns.
Can anybody tell me of their experiece with the rcbs 150swc as far as accuracy with mild to hot loads. Maybe I'm looking for the holy grail [ a pb boolit for general all purpose use]. Cast with ww the 358477 shoots great with up to 5.5 gr. unique but accuracy goes south with anything more.
Appreciate everyone's willingness to help
Kirk

[Kirk Miller]

45r
Your thoughts on long heavy boolits for the 357 are thought provoking. The 358665 is a fairly long rnfp boolit with a lot of bearing surface and I have no complaints as long as velocity is kept low, but the frustration starts with any increase. What are the opinions where the bevel base is concerned. Is it possible that the bevel is allowing gas cutting, thereby destroying accuracy?
Kirk

[floodgate]

Kirk:

"So far in my GP100, the lyman 358665 UNDER 5.5gr. unique has been very accurate. The problems start..."

I think I've found the source of your problem...

(Just funnin'; I've been known to make the same mistake.)

Doug

[9.3X62AL]

Kirk and Ham--

Welcome to the Poured Projectile Project Room, gents.

Welcome also to the world of multiple variables that produce madness--a sub-section of the boolit casting brotherhood in which all casters find themselves at some point.

I'm guessing from your stated as-cast weights that your alloy is a fairly lead-rich and soft one. If dimensions within the revolvers are good--and the boolits correspond correctly to those dimensions, we are left with metallurgy as a possible cause. Your lube should be all right.

In my use of #358477 in 38 Specials, most revolvers shoot them very well for me up to about 1000 FPS, where we are venturing into +P territory. At some point from 1000 FPS to 1150 FPS, most plain-based boolits in most of my revolver calibers fall off the shelf and land on their aspirations, and #358477 is no different. I have avoided its use in 357 Magnum for this reason, resorting to Lyman #358156 for full-snort Magnum loadings.

One exception to this rule for me has been Lyman #358430, a 195 grain RN that stays accurate well past 1200 FPS in my Ruger BisHawk x 7.5" and past 1100 FPS in my M-686 x 4". It is kind of a heavy-for-caliber boolit, but has been a steady and accurate performer for me for many years in both 38 Special and 357 Magnum calibers. Perhaps its length and 4 drive bands account for this--it grabs the rifling well and doesn't allow propellant gases past its base or supplemental drive bands. I will be casting it in soft-point fashion for my local deer hunt next year, and running it to 1200 FPS to make venison with.

In my nearly 30 years of messing around with 38 and 357 rollers, I haven't been able to get plain-based boolits to do The Right Things for me at higher velocities--with the exception of the one boolit mentioned herein. That experience extends into the 41 and 44 Magnums and 45 Colt as well. These days, 90%+ of my Magnum revolver shooting occurs at 900-1100 FPS. Life is just simpler and cheeper without gas checks. When I do crimp a gas check onto a #358156, there's a good chance it will be stepping out of the Ruger at 1500 FPS+. Not a stunt for my 686 or M-27, and the muzzle signature lights up adjacent hillsides at dusk in a very satisfying fashion. Long live ball powders--WW296 ROCKS!

[45r]

I don't use bevel base boolits.Never had any luck with them shooting as well as the other designs.Heat treating PB boolits to 450 degrees and emersing them in cold water will make them shoot better at higher pressures.There is a sweet spot where a PB boolit shoots well.If you go over that spot with too much pressure accuracy goes away.

[Kirk Miller]

9.3x83AL
Thanks
Your reply is exactly what I was looking for. At least 95% of my shooting is 900-1000 fps. Like I said, I was hoping for a dual purpose boolit and your answer confirms the fact that it 'just aint gonna happen'. Now for the next $ 66.ooo question. Out of the multiple 158gr. gc swc's which one has proven to be the most {usually} accurate one?
Thanks
Kirk

[9.3X62AL]

Kirk--

Never say "never", never say "always" when it comes to cast boolits. I haven't found a good "dual purpose" 158 grain-class boolit of plain-based design for the 357, but other shooters with other guns can and have had other/differing experiences.

If I had to choose ONE boolit for 357 Magnum usage that gives good accuracy from 700 FPS to 1500 FPS......#358156 would get my vote. Those gas checks at almost 3 cents each really boost projectile costs skyward, but they do shoot well throughout the entire spectrum. I haven't had much luck shooting gas check designs in a "checkless" condition--but again, other shooters have done so very successfully.

There seems to be a lot of variance between #358429 designs, as your second post alludes to. I got into the #358429 kinda late in the game, about 4-5 years ago. My version falls out at .360", and all three drive bands are touched by a .359" size die that sizes true diameter with 92/6/2 alloy. Its base band is kinda short, outside Mr. Keith's specs for three bands of equal length. I haven't done any work with it in 357 Magnum over 900 FPS, but it shoots very well at that speed/pressure.

Regarding your current wide-bodied #358429........that mould would be a real find for a 38 S&W shooter. If it were mine, I would prep it for the 38/357 by sizing and lubing in my .363" die FIRST, and get the grooves filled with incompressible lube. THEN run it into a die .002"-.003" smaller, and a third die if needed. Time consuming and a PITA, but the grooves won't collapse on ya. Lyman has .363" sizer dies as regular-stock items, mine came from Midway about 2 years ago.

I absolutely, positively LOATHE bevel-based boolits. Period.

[Bret4207]

Agree with Al, as usual. Bevel base boolits have been mostly a disaster for me. As for a GC design it's pretty hard to say anything bad about the 358156, either solid or HP. I've shot that design well past the, "Holy freakin' crap!!!" category in a Colt Cobra, S+W 19 and 28. I presume it will perform as well or better in my 35 Rem Marlin too. It's an easily obtained mould in single, double and 4 cavity moulds.

As for your plain base issues I'd find the most accurate load you can and be happy with it. If it only gives you 850 fps thats no problem. 99% of your shooting in 38's and 357 can be handles within that area, at least IMO. The 358477 with it's square base and excellent design has passed 1100fps (estimated speed) for me with little problem, but that was with one gun and an unknown WW alloy that I no longer have. I haven't tried pushing things to that speed since.

Water drop some of those problem boolits and see if that helps. I've ahd good luck with it and am not much on the oven heat treating method, but YMMV.