couple RMR bullet questions?

[Axis II]

I just got around to doing load workups with RMR RN, FP, JHP, and plated and searched a few threads on here for OAL and and my Hornady manuals info. Hornady's data plunks fine in my S&W M&P 9MM 4.5'' barrel. I have a few concerns though and would like your opinions.

124gr-RN--1.140OAL---3.9-4.4gr HP-38
124gr-FP----1.060--------3.9-4.4gr HP-38
124gr-MPR JHP--1.055--3.9-4.4gr HP-38.

With the JHP and FP it seemed to me there was a lot of bullet in the case and might cause excessive pressure but my first workup of RMR RN I needed 4.3-4.4gr HP38 at 1.130 to be accurate and while the gun cycled and was semi accurate with lower charges the cases would sometime hit my arm and not eject all the way. I figured up the OAL a little for the higher charges.

What are you guys loading the JHP and FN to with HP38? '

Any issues with my OAL and all the bullets? I colored all the rounds with a dark blue and black sharpie and plunked them and turned them in the barrel and no marks exept on the FN I got a slight mark close to the case mouth but it plunked and fell out fine. Upon doing some experiments the JHP started to plunk at 1.075-1.180 which I didn't like so I went with what I found on here and what Hornady said. The FN plunked really high in OAL also but I went with what I found on here and the Hornady manual.

 

[vaalpens]

I don't have much experience with the RMR 124gr FMJFN in 9mm, but following is the chrono data I have for HP38. I have not seen any good accuracy yet with the FN and HP38, but I have only done limited load development.

9mm, SP2022, 3.9"
Case: Blazer
COL: 1.065"
RMR, 124gr, FMJFN, HP38, 4.2gr, CCI500
Average: 1005
ES: 13
SD: 6
Force: 278
PF: 124
Velocities: 1014, 1001, 1001, 1010, 1002
Grouping @ 15yards: 1.69"

9mm, SP2022, 3.9"
Case: Blazer
COL: 1.065"
RMR, 124gr, FMJFN, HP38, 4.3gr, CCI500
Average: 1017
ES: 28
SD: 11.4
Force: 285
PF: 126
Velocities: 1023, 1029, 1024, 1011, 1001
Grouping @ 15yards: 1.63"

9mm, SP2022, 3.9"
Case: Blazer
COL: 1.065"
RMR, 124gr, FMJFN, HP38, 4.4gr, CCI500
Average: 1039
ES: 26
SD: 10.5
Force: 297
PF: 128
Velocities: 1031, 1037, 1056, 1041, 1030
Grouping @ 15yards: 1.95"

9mm, SP2022, 3.9"
Case: Blazer
COL: 1.065"
RMR, 124gr, FMJFN, HP38, 4.5gr, CCI500
Average: 1057
ES: 16
SD: 6.8
Force: 308
PF: 131
Velocities: 1054, 1067, 1052, 1051, 1061
Grouping @ 15yards: 1.48"

 

[Dudedog]

I can load the MPRs to 1.08 for some of my guns but have loaded them at 1.06 for in testing.
Going from 1.08 to 1.06 with 4.4grs of WSF (mild-medium 128 PF load about 1025 at 1.08, I picked up about 30 fps going to 1.06)
If it was me I would back off to 3.7 for the start load with the MPRs, maybe the same for the FNs. Don't know what you are after, practice, minor PF, most vel you can get??
Haven't done as much testing with the MPRs and FNs as I would like but in limited testing the MPRs seem a little faster than the FNs at the same OAL.

If you look at Hodgdon's numbers for a 125 HAP (.356 dia shorter OAl) they are a lot lower.

5" 9mm 1911, mixed range brass, S+B SP, outside temp 90ish WSF (not HP38)
But might be helpful

String: 5
Date: 9/17/2017
Time: 11:24:26 AM
Grains: 124
Hi Vel: 1037
Low Vel: 1012
Ave Vel: 1021
Ext Spread: 25
Std Dev: 9
RMR MPR JHP 4.4-4.5 WSF 1.08 (call it 4.45gr, Frankford DS750 round to .x some 4.4 some 4.5)
Velocity Power Factor Ft/Lbs
1021 126.604 286.995
1018 126.232 285.311
1012 125.488 281.958
1020 126.48 286.433
1037 128.588 296.061

String: 1
Date: 9/17/2017
Time: 11:52:56 AM
Grains: 124
Hi Vel: 1068
Low Vel: 1040
Ave Vel: 1055
Ext Spread: 28
Std Dev: 10
RMR MPR JHP 4.4 WSF 1.065 (less powder in the hopper these all seemed to come in at 4.4 with may 1 or 2 4.5 thrown in)
Velocity Power Factor Ft/Lbs
1058 131.192 308.173
1050 130.2 303.53
1059 131.316 308.756
1040 128.96 297.776
1068 132.432 314.026

 

[Axis II]

I can load the MPRs to 1.08 for some of my guns but have loaded them at 1.06 for in testing.
Going from 1.08 to 1.06 with 4.4grs of WSF (mild-medium 128 PF load about 1025 at 1.08, I picked up about 30 fps going to 1.06)
If it was me I would back off to 3.7 for the start load with the MPRs, maybe the same for the FNs. Don't know what you are after, practice, minor PF, most vel you can get??
Haven't done as much testing with the MPRs and FNs as I would like but in limited testing the MPRs seem a little faster than the FNs at the same OAL.

If you look at Hodgdon's numbers for a 125 HAP (.356 dia shorter OAl) they are a lot lower.

5" 9mm 1911, mixed range brass, S+B SP, outside temp 90ish WSF (not HP38)
But might be helpful

String: 5
Date: 9/17/2017
Time: 11:24:26 AM
Grains: 124
Hi Vel: 1037
Low Vel: 1012
Ave Vel: 1021
Ext Spread: 25
Std Dev: 9
RMR MPR JHP 4.4-4.5 WSF 1.08 (call it 4.45gr, Frankford DS750 round to .x some 4.4 some 4.5)
Velocity Power Factor Ft/Lbs
1021 126.604 286.995
1018 126.232 285.311
1012 125.488 281.958
1020 126.48 286.433
1037 128.588 296.061

String: 1
Date: 9/17/2017
Time: 11:52:56 AM
Grains: 124
Hi Vel: 1068
Low Vel: 1040
Ave Vel: 1055
Ext Spread: 28
Std Dev: 10
RMR MPR JHP 4.4 WSF 1.065 (less powder in the hopper these all seemed to come in at 4.4 with may 1 or 2 4.5 thrown in)
Velocity Power Factor Ft/Lbs
1058 131.192 308.173
1050 130.2 303.53
1059 131.316 308.756
1040 128.96 297.776
1068 132.432 314.026

I started at the 3.9 cause that was the lowest start I could find in 2 manuals and Hodgdon. I don't have a chrony but I've taken extreme, berry's and RMR RN to 4.4 just to see and settled on 4.2-4.3. anything lower it flings the brass up in the air and it comes down on my arms so I hiked it up a little to throw it on my tarp. We do steel targets so PF might come into play. Hunting season is in now so I don't attend the pistol matches anymore until spring. The other matches they do some funky lets see how many targets you can hit, how fast at 25yards so I would imagine the extra velocity would help me a little on that.

 

[thomas15]

May I ask what are the ballistic coefficients for the 9mm RMR bullets in this discussion?

 

[LiveLife]

BC? We are loading pistol rounds ...

For short distances we are shooting these projectiles (15-25 yards), I don't think we'll see enough measurable deviation of trajectory from air resistance.

I mean, bullseye match shooters use full wadcutters with flat nose ...

 

[thomas15]

Then why all of the RMR specific gibber jabbering?

 

[WessonOil]

I typically use 4.3 grains of HP-38 with 124 grain RMR RN plated and jacketed at about 1.145-1.15 OAL.

This is the minimum load to reliably cycle the slides on my M&P's, knock down steel, and fall within my Lee Autoloader Disks.

 

[Doublehelix]

I am also loading the RMR JHP (MPR) to 1.06", and the RMR RN to 1.125".

Here is some data using HP-38 with the RMR JHP bullets, BUT THESE WERE LOADED TO 1.125". When I first starting loading the JHPs, I loaded them long as they shot well in my SIG P226. I found out later that they would not plunk in any of my other guns, so I had to load them shorter to 1.06". I have been loading them with TiteGroup, so I do not have any data at that shorter COAL with HP-38.

All of these loads were "soft shooters", and I liked them a lot. My favorite out of the 3 loads were the 4.3 gr. loads

-----

Bullet Type: RMR JHP 124
Powder: HP-38
Weight: 4.3 gr
COAL: 1.125
Primer: CCI 500
Case: Federal

Stats - Average 1083.75
Stats - Highest 1105.93
Stats - Lowest 1057.85
Stats - Ext. Spread 48.08
Stats - Std. Dev 17.21
Avg Power Factor 131.67

-----
Bullet Type: RMR JHP 124
Powder: HP-38
Weight: 4.4 gr
COAL: 1.125
Primer: CCI 500
Case: Federal

Stats - Average 1103.46
Stats - Highest 1120.29
Stats - Lowest 1085.99
Stats - Ext. Spread 34.31
Stats - Std. Dev 13.84
Avg Power Factor 133.78
-----

Bullet Type: RMR JHP 124
Powder: HP-38
Weight: 4.5 gr
COAL: 1.125
Primer: CCI 500
Case: Federal

Stats - Average 1116.89
Stats - Highest 1137.82
Stats - Lowest 1105.25
Stats - Ext. Spread 32.57
Stats - Std. Dev 9.44
Avg Power Factor 135.28

 

[Dudedog]

The MPR JHPs at 1.065 OAL give about the same vel as the RNs at 1.12 with .2 less WSF.
I don't think I have any of the RNs left but I can load some of the JHPs tomorrow at 1.055 with HP38 and chrono them if I can make it to the range this weekend.
Will do some of the FNs at 1.06 as well.

Then why all of the RMR specific gibber jabbering?

OP is after data for specific bullets.
Also because of the profile of the MPR JHP it needs to be loaded short for some guns, (not a bad thing, gives it a long bearing surface and lets it work in ,.357 Sig) and OPs gun in one of those that need it loaded shorter
than the normal OAL for an "average" 125 JHP.
They are excellent bullets for a great price from a company that offers super service so lots of people tend to be interested in them, (also fairly new) so not a lot of data out there yet.
So that's what the RMR jibber gabber is about.

 

[LiveLife]

RMR 124 RN, FP, JHP ... HP38 ... Any issues with my OAL and all the bullets?

why all of the RMR specific gibber jabbering?

profile of the MPR JHP it needs to be loaded short for some guns ... OPs gun is one of those that need it loaded shorter than the normal OAL

So that's what the RMR jibber gabber is about.

Yes, RMR sells two different 124 gr JHP bullets, one with longer nose (like Speer Gold Dot HP) that can be loaded to typical 1.125" OAL and shorter MPR that needs to be loaded to shorter 1.050".

For my Lone Wolf barrel with no leade, I am using the following OALs and even with deeper bullet seating depth, W231/HP-38 being dense powder, no concern for powder compression up to Hodgdon max charges. If your barrel/pistol reliably feeds longer working OALs, even less worries for powder compression and pressure concerns.

If I am using much shorter than published OAL/bullet seating depth, I will initially reduce start/max charges by .2-.3 gr for my load development while watching chrono numbers.

 

[Axis II]

The MPR JHPs at 1.065 OAL give about the same vel as the RNs at 1.12 with .2 less WSF.
I don't think I have any of the RNs left but I can load some of the JHPs tomorrow at 1.055 with HP38 and chron them if I can make it to the range this weekend.
Will do some of the FNs at 1.06 as well.


OP is after data for specific bullets.
Also because of the profile of the MPR JHP it needs to be loaded short for some guns, (not a bad thing, gives it a long bearing surface and lets it work in ,.357 Sig) and OPs gun in one of those that need it loaded shorter
than the normal OAL for an "average" 125 JHP.
They are excellent bullets for a great price from a company that offers super service so lots of people tend to be interested in them, (also fairly new) so not a lot of data out there yet.
So that's what the RMR jibber gabber is about.

Yes, RMR sells two different 124 gr JHP bullets, one with longer nose (like Speer Gold Dot HP) that can be loaded to typical 1.125" OAL and shorter MPR that needs to be loaded to shorter 1.050".

For my Lone Wolf barrel with no leade, I am using the following OALs and even with deeper bullet seating depth, W231/HP-38 being dense powder, no concern for powder compression up to Hodgdon max charges. If your barrel/pistol reliably feeds longer working OALs, even less worries for powder compression and pressure concerns.

If I am using much shorter than published OAL/bullet seating depth, I will initially reduce start/max charges by .2-.3 gr for my load development while watching chrono numbers.

Gentlemen thank you for your help and dude dog for helping me with these a few months ago.

I was just concerned with how much of the bullet was in the case compared to all the plated and RMR RN i have dealt with and wanted to make sure everything was okay. I know to workup and i did in 5rd batches for each bullet. 3.9-4.4. As said before i must have a heavy spring cause i needed 4.3-hp38 with the RN seated a little deeper to get them to throw away from me instead of at me. My clubs pistol range gets hammered and becomes a muddy, dirty mess so i take a tarp to save my brass but don't want to stand on the tarp and get it muddy and 4.0-4.1 would just toss them far enough to not make it to the tarp and sometimes i would get hit in the arm/hand and i figured it was too light. If i can get these to cycle at the lower charges ill be happy with that cause i don't need to meet PF cause we mainly shoot paper at my club in matches.

 

[Dudedog]

Your welcome

 

[Dudedog]

Loaded up some of the 124gr MPR JHPs with HP38.
3.7, 3.9, 4.1 and 4.3.
Will try to chrono this weekend.

Loaded up some FNs with 4.0 Gr @ 1.08, 1.065 and 1.06 ( small OAL ladder)

 

[Axis II]

Loaded up some of the 124gr MPR JHPs with HP38.
3.7, 3.9, 4.1 and 4.3.
Will try to chrono this weekend.

Loaded up some FNs with 4.0 Gr @ 1.08, 1.065 and 1.06 ( small OAL ladder)

thanks, I look forward to seeing the results.

 

[longdayjake]

Dudedog, we had some people test them with HP38/Win231. They only did okay. It's a weird powder that seems to give pretty high ES numbers. CFE pistol and BE 86 are what the loading companies have settled on for accuracy and consistency. Not that hp38 isn't a great powder. It was all I used for about a decade.

 

[Axis II]

Dudedog, we had some people test them with HP38/Win231. They only did okay. It's a weird powder that seems to give pretty high ES numbers. CFE pistol and BE 86 are what the loading companies have settled on for accuracy and consistency. Not that hp38 isn't a great powder. It was all I used for about a decade.

I plan on trying something else when this pound is gone. I have done this with 223 and finally after about 4 powders found one better then the others.

whats an ES number?

 

[Doublehelix]

I plan on trying something else when this pound is gone. I have done this with 223 and finally after about 4 powders found one better then the others.

whats an ES number?

ES = "extreme spread"

Meaning the difference between the fastest recorded velocity in a string and the lowest recorded velocity in a string. (Chronograph readings.) The lower the ES, the more consistent the charge.

 

[Walkalong]

The more consistent the results.

 

[Axis II]

I finally made it to the range yesterday to test the new RMR bullets and I was kind of shocked how much better the RN shot compared to the FN.

Anyone have any suggestions how to tighten these up a bit? 5 shots with each charge fired at about 10yards freehand with a s&w m&p9 4.5'' barrel. powder was hp-38 with mixed cases and S&B primers.

 

[Axis II]

Pics are attached

 

[ArchAngelCD]

Anyone have any suggestions how to tighten these up a bit? 5 shots with each charge fired at about 10yards freehand with a s&w m&p9 4.5'' barrel. powder was hp-38 with mixed cases and S&B primers.

When you are shooting free hand without using a rest it's difficult to know if the load is at fault or the shooter. Before you start changing things you really should shoot those loads off a rest as steady as you can.

 

[Walkalong]

Free targets. Print some.

 

[LiveLife]

Here's a printout target I made for testing loads. Grid is one inch square to help approximate shot groups with room for notes.

https://www.thehighroad.org/index.php?attachments/target-pdf.134526/

 

[Axis II]

When you are shooting free hand without using a rest it's difficult to know if the load is at fault or the shooter. Before you start changing things you really should shoot those loads off a rest as steady as you can.

I am going to do that as well. I just didn't get how the RN shot better then FN. I will do another workup and shoot off my rifle sand bag.