Some history, from Glen Fryxell
Yea, I read that already. Seems like they are all basically the same, and load data should be nearly interchangeable between the H&G 503, 429421, and RCBS 429-250K. SEEMS LIKE. But I don't know. Glen doesn't provide relevant details that matter, weight with a given alloy, groove to meplat, length, meplat diameter, are all the bands the same width, full diameter? A scaled drawing like NOE provides would be great.
Since Lyman's molds have proven to me to be of various actual diameters (I own three 358429s and NONE of them cast the same diameter bullet, and one has its handle retaining screw drilled at an angle so it needs to use specially modified handles to hold it), I was going to go for the MP molds #503 mold, since I know it will be good out of the box. But I want to know if I can use 429421 load data or RCBS 429-250K load data. Please don't waste everyone's time saying probably. If have the Lyman 429421 and a H&G 503 clone from MP molds please chime in if you KNOW the weights. It would be greatly appreciated.
MP copy of H&G#503, alu 6cav solid
2/3 pure,1/3 ww=266grs
ww=262grs
ww+Lino=261grs
Hope it helps.
The forward drive band is longer and is actually inside the throats of my Colt. The 503 was designed after the 44 Mag and has whatever improvements Elmer came up with.
I like the MP Molds/Dale 53 503 clone, the Arsenal 503 clone and the out of production BC 1103. I have seen several different Ideal #503s and like the Dale 53 (who supplied dimensions) version.
The 2 Lyman 4c 429421s I had were undersize and tapered with the forward band .002" under. I lapped one straight and like it now.
NOE makes a great mold and has 3 different Elmer's but I like a deeper crimp groove.
The only thing that kept me from RCBS is the 2 cavity limit.
The MP Molds/Dale 53 503 clone.
Last edited by Mal Paso; 02-05-2020 at 10:50 PM.
Mal
Mal Paso means Bad Pass, just so you know.
All of these are roughly WW+ 1% or a bit more Tin. There are lubed, I pulled a couple from each box.
MP 503 .432" 260 g
Arsenal 503 .432" 255g
Lyman 429421 (lapped to .432") 252g
BC 1103 244g
I load them all the same.
Mal
Mal Paso means Bad Pass, just so you know.
I seem to remember Keith did NOT like the RCBS bullet.
The driving bands were a 3 different heights, with the top driving band being very narrow.
I have the RCBS mold and while it shoots ok, someday I'm going to send it off to ERIK for "band modification" and get all 3 driving bands cut to matching heights.
The 3 Lyman #429421 molds I have are from the mid 1960's, a 4cav drops .4315 with my preferred alloy. A mix of 50/50 - COWW/#2.
The pair of 2cavs will drop .431 & .4315 in the 1st mold and .430 & .431 in the 2nd mold.
All these molds are accurate and produce good bullets. I just Don't like the RCBS; the bullets uneven appearance.
Haven't seen a H&G 503 since My Dad passed, 32yrs ago. So I can't speak about it.
I HATE auto-correct
Happiness is a Warm GUN & more ammo to shoot in it.
My Experience and My Opinion, are just that, Mine.
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My 429421 mold is an NOE and of course I have the RCBS 44-250. I have the MP mould but only cast HP's with it. Both the NOE and RCBS cast virtually the same weights with ACWW and that is 258-260 grs. Using identical loads the RCBS bullet runs just a bit slower (~35 fps)due to the fact that the distance from the crimp groove to the bottom of the bullet is slightly less where the RCBS is concerned. This of course means slightly less bullet in the case, slightly less pressure and slightly less velocity.
Bullets from the RCBS mold consistently give superb accuracy and so far I've taken three (or is it four?) deer with said bullet.
The only non-HP bullet I've ever recovered from game was from the RCBS mold. It struck a buck just behind the last rib on his left side at about 1050 fps and travelled up to the juncture of the neck and shoulder on the right side.
Hope this helps.
35W
The biggest waste of time is arguing with the fool and fanatic who doesn't care about truth or reality, but only the victory of his beliefs and illusions.
There are people who, for all the evidence presented to them, do not have the ability to understand.
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Wow thanks. I think will be be getting MPs version of the 503. Maybe I should get Arsenal's clone for a solid and MP's HP. I've been burned so many times with used lyman molds off ebay. I think there is a reason why they are on ebay...
I am planning on shooting this in 44 Special in a 624. Are there any nose length considerations there like for the 357 N frames (I sold a M28 for want of loading 358429s in maggie brass)? 624s are do NOT have recessed chambers, so I figured with Special brass it won't be problem.
I suppose I better pin gauge the throats first too since the 503 seems like it could run into them.
Last edited by curioushooter; 02-07-2020 at 01:32 PM.
I would measure the throats. Smith usually has enough distance to the throats but every gun is different and Smith had tight throats for a while. I reamed all my throats .4313 that weren't larger already. My 629 throats were .428. Only my Colt has chambers short enough that the 503 forward band is just inside the throats. I consider that a good thing, no jump to the throats.
The MP Hollowpoint Molds are just plane fun. I had trouble with the MP 6 cavity mold but I understand the alignment pins are cross pined now. I also have the Arsenal 5 cavity which has a conventional sprue plate. The MP 6 cavity is Lee style and you have to be more careful closing the mold so as not to push the blocks out of alignment.
Mal
Mal Paso means Bad Pass, just so you know.
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |