Just curious what charge you guys are using for 124gr RMR FMJ with HP-38? Ive pushed extreme 124gr to 4.3gr without issues but my hornady manual doesn't show that powder for a 124gr FMJ so I checked lyman for the 125gr and 231 max is 4.4 but hodgdon says I can push a sierra 124GR FMJ to 4.8gr HP-38. my seating depth is 1.135-1.140 and 1.150 will plunk but to me that's a little long.
RMR 124gr & HP-38?
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which one? Hodgdon or lyman? I plunked 1.150 per hornady manual for that gr bullet but it felt a little tight so I took the recommendations from here on the 1.135 and 1.140. I figured try several charges at each OAL to see what shoots the best.
THANKS! JUST CLARIFYING!
Doublehelix
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LiveLife
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Use the OAL/COL that works for your barrel before doing powder work up. With most 124/125 gr FMJ/RN plated bullets, 1.120"-1.150" work in most barrels (I think Hodgdon may have used longer 1.150" for Berry's HBRN-TP due to longer bullet base hollow base produces). If longer OAL works, once an accurate powder charge is identified, consider decreasing the OAL incrementally without compressing the powder to identify more accurate load (from greater neck tension).
I load for multiple barrels and RMR 124 gr FMJ with 4.3 gr of W231/HP-38 loaded to 1.130-1.150" (Longer OAL for less dense powder to not compress powder charge) with .378" taper crimp works well in all of them. For my newer Lone Wolf barrel with almost no leade, I need to use shorter 1.110"-1.115" OAL. FYI, RMR 115/124 gr FMJ/JHP bullets are sized at .3555" - https://www.thehighroad.org/index.p...re-sized-the-same.818806/page-2#post-10567453
Hodgdon lists W231/HP-38 (They are same exact powder) max charges for 124 gr Berry's thick plated RN with 4.4 gr using 1.150" OAL/COL (which is close to lead load data) and 125 gr Sierra FMJ with 4.8 gr using 1.090" (Chances are, lower max charge listed is from larger sizing of bullet at .356" compared to .355" sized FMJ) - http://www.hodgdonreloading.com/data/pistol
Since most FMJ and plated bullet weight can vary up to .1 grain, you can interchange load data for 124 gr and 125 gr bullets with same/similar nose profile of FMJ/RN.
125 gr Lead Cone Nose W231/HP-38 Diameter .356" COL 1.125" Start 3.9 gr (1,009 fps) 25,700 CUP - Max 4.4 gr (1,086 fps) 31,200 CUP
124 gr Berry's (BERB) HBRN-TP W231/HP-38 Diameter .356" COL 1.150" Start 3.9 gr (920 fps) 27,400 PSI - Max 4.4 gr (1,037 fps) 31,900 PSI
125 gr Sierra (SIE) FMJ W231/HP-38 Diameter .355" COL 1.090" Start 4.4 gr (1,009 fps) 24,600 CUP - Max 4.8 gr (1,088 fps) 28,800 CUP
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ArchAngelCD
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I have used those bullets with 4.8gr W231 with an OAL of 1.125" so you should have no problem. Just a note, I found the best accuracy with a charge of 4.6gr W231.
Only you can determine how high you can push things. I don't push things, so I can't tell what MY bullet at MY COL with MY lot of powder would do, and it might not matter as you aren't shooting my gun.
You start at the start load (I start at the lowest start load) and work up.
Any time you go to a new bullet or a new COL, start back at the start load.
Based on about twelve manuals, I can say with some hesitation that the max load will most likely be between 4.2 (1071 fps) and 5.0gn (1130fps), so I would not start any higher than 4.0gn and would actually start at 3.5gn (where all the start loads range from 2.9-3.9gn).
You start at the start load (I start at the lowest start load) and work up.
Any time you go to a new bullet or a new COL, start back at the start load.
Based on about twelve manuals, I can say with some hesitation that the max load will most likely be between 4.2 (1071 fps) and 5.0gn (1130fps), so I would not start any higher than 4.0gn and would actually start at 3.5gn (where all the start loads range from 2.9-3.9gn).
I've loaded a few thousand of the RMR 124 Plated RN with that charge due to it being a Lee Autodisk charge.
I tend to load at about 1.145-1.15 OAL.
This cycles my slide and gives me enough power factor to knock over steel in competition.
FYI, you may try 4.0 grains of TiteGroup if you're looking for lighter recoil.
Be sure and check slide function before you load up a ton.
I load most 115 to 124/5 Gr RN bullets in 9MM to 1.130 to 1.135 OAL. Like Hodgdon, I loaded the Berrys 124 Gr HBRN a little longer at 1.140 to 1.145 OAL.
Noylj gives good advise. Start low, work up, see where what you like in terms of recoil and accuracy come together.
N320 and a 124 at 1050ish is pleasant and accurate. Silhouette or N330 at 1150ish is the same. W-231 should fall n there somewhere.
Noylj gives good advise. Start low, work up, see where what you like in terms of recoil and accuracy come together.
N320 and a 124 at 1050ish is pleasant and accurate. Silhouette or N330 at 1150ish is the same. W-231 should fall n there somewhere.
thanks guys. I know to workup from start to an accurate load but when you look at 3 different datas and get a huge spread its like who do you go with?
for the extreme 124gr I was shooting I went from lead data start 3.8-4.3 and found a sweat spot in at 4.2-4.3gr. since changing to an fmj and probably a differently molded bullet I had a slight concern about starting at say 4.0gr and going up into hodgdons data. I know with some powders like H110 you have to be right on the money with min and max from what several people have told me so I wasn't sure if that was the case with hp-38. Also, not having it in the hornady manual gave me a little skepticism. as you guys taught me over the years is double check everything!
for the extreme 124gr I was shooting I went from lead data start 3.8-4.3 and found a sweat spot in at 4.2-4.3gr. since changing to an fmj and probably a differently molded bullet I had a slight concern about starting at say 4.0gr and going up into hodgdons data. I know with some powders like H110 you have to be right on the money with min and max from what several people have told me so I wasn't sure if that was the case with hp-38. Also, not having it in the hornady manual gave me a little skepticism. as you guys taught me over the years is double check everything!
LiveLife
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Sweat spot? You are working your bullets too hard.
Keep in mind that X-Treme 124 gr RN is sized .355" and RMR 124 gr FMJ is sized slightly larger at .3555".
Chances are you may find your sweet spot again around similar powder charge range.
I must have a heavy spring cause they would barely eject and accuracy was horrible. I played with seat depth and it was okay but I went from 4.2-4.3 and I can dump a mag into a 5x5 card at 20ft.Sweat spot? You are working your bullets too hard.
Keep in mind that X-Treme 124 gr RN is sized .355" and RMR 124 gr FMJ is sized slightly larger at .3555".
Chances are you may find your sweet spot again around similar powder charge range.
Well I finally got to test this combo. I did 10rds at 1.135 and 1.145 with 4.2gr HP-38 and fired from 10yards. All 10 shots with 1.135 OAL grouped softball size and tighter groups. 1.145 opened up a bit so I'm thinking 1.135 with 4.2gr will be my load. this charge still barely ejects them but good enough for me. I did have what appeared to be a little primer flow with s&b primers.
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