RMR 9mm MPR Jacketed Hollow Point OAL

Status
Not open for further replies.
W

wannabefree

Member
Joined
Aug 10, 2019
Messages
37
Location
State of Jefferson AKA Northern Rural Ca.
I ordered some of these RMR 124gr Jacketed Hollow Point ( Multi Purpose Rounds) about a month ago and today they arrived in the mail. This is the first time I have used these and am trying to put together some starting load work ups. I am a little confused on the data I have found as to OAL since these are pretty short and there are no other bullets I have found that match up to them. I have seen varying OAL lengths listed on the web anywhere from 1.04 to 1.135 most are listing at 1.06 to 1.10 which seems about right but I still am not sure where to start. I know that it is also dependent on how they chamber in your particular gun but I am trying to load for multiple guns so I need reference point to start out with.
My initial test gun will be a Glock 17 but also have a G26 and S&W Shield and want a multipurpose round for all of them. In the past I have not found any of my guns to be particular about any factory ammo or any of my past reloads accept when I try to load too light and get a few fail to ejects on my G26.
It probably does not matter for my initial test loads but I plan on using BE-86 powder Starting at about 5.2gr and working up to maybe 5.8gr. On the higher end the OAL could play a big factor in pressure so I am hoping to get some solid information on where others have had success.
 
I Normally load them 1.08 to 1.09, works in my Springfield 9mm 1911, Taurus PT99, Springfield XDs, and Sig P226.
Find the longest OAL that will plunk in your guns, so you know how long you can go.

Maybe just me but I think 5.8gr of BE86 might be pushing it a bit unless your OAL is up there around 1.13.

Mixed range brass, S+B SP, charges as thrown after setting measure
5" 9mm 1911
Time: 10:30:36 AM
Grains: 124
Hi Vel: 1179
Low Vel: 1087
Ave Vel: 1132
Ext Spread: 92
Std Dev: 33
RMR 124 124 HP5.4 BE86 1.08 OAl
Velocity Power Factor Ft/Lbs
1121 139.004 345.967
1143 141.732 359.68
1087 134.788 325.299 (this one messed up my ES and SD, but small sample)
1134 140.616 354.038
1179 146.196 382.693

PS: I really like the 124 MPRs, great bullet, great company.
 
Last edited:
Dudedog posted while I was typing and provided good data.

RMR MPR does not have the "typical" JHP profile as it has similar nose profile as RNFP and I need to load it shorter to clear the rifling. If you compare the RN loaded to 1.130" to MPR loaded to 1.050", MPR looks like RN with tip of nose taken off.

index.php


Following comparison picture shows a sample of RMR 9mm bullets and working OALs that will work in most factory barrels.

index.php

wannabefree said:
RMR 124 gr Multi Purpose Rounds ... Glock 17 but also have aG26 and S&W Shield
Click to expand...
Below is a listing of factory and aftermarket barrels with longer leade to shorter leade and max/working OAL for each barrel from this thread - https://www.thehighroad.org/index.p...let-max-working-oal-col-for-reference.848462/

KKM 9mm 124 gr MPR - 1.115"
Shield 9mm 124 gr MPR - 1.105"
Tactical Kinetics 9mm 124 gr MPR - 1.055"
Lone Wolf 9mm 124 gr MPR - 1.040"

Since M&P Shield has shorter leade than Glock barrels, using 1.105" OAL would work in all the barrels you have. But if you want to load for other factory/aftermarket barrels with shorter leade, using 1.050" OAL will work for most of them.

wannabefree said:
I plan on using BE-86 powder Starting at about 5.2gr and working up to maybe 5.8gr. On the higher end the OAL could play a big factor in pressure so I am hoping to get some solid information on where others have had success.
Click to expand...
Here's Alliant load data for BE-86 and 124 gr JHP - https://www.alliantpowder.com/reloa...wderlist.aspx&type=1&powderid=38&cartridge=23
  • 9mm 124 gr JHP BE-86 COL 1.120" Max 5.9 gr (1,175 fps)
And here's Speer load data for BE-86 and Gold Dot HP you can reference for your load development and powder work up - https://www.speer-ammo.com/download...m_caliber_355-366_dia/9mm_Luger__124_rev1.pdf
  • 9mm 124 gr Speer Gold Dot HP BE-86 OAL 1.120" Start 5.4 gr (1124 fps) - Max 6.0 gr (1199 fps)

FYI, 124 gr Gold Dot HP has bullet length of .570" - http://www.shootforum.com/forum/bulletdb.html

And RMR 124 gr MPR has bullet length of .558" - https://www.thehighroad.org/index.php?threads/hornady-and-rmr-bullet-lengths.865945/#post-11446057


If you end up using 1.105" as your working OAL, I would consider reducing start charge to 5.2 gr and working up 5.4, 5.6 and 5.8 gr while looking for accuracy trends.

If you end up using 1.050" as your working OAL, I would consider reducing start charge to 5.0 gr and working up 5.2, 5.4 and 5.6 gr while looking for accuracy trends.
 
Last edited:
Good information so far. I will need to do a few dummy test rounds with varying OAL and see just what the longest overall length fits all my guns and go from there. From what I see so far I am thinking I will end up around 1.1 OAL and starting out with about 5.2gr and working up to around 5.6gr or so. I am not looking for super hot loads just want to replicate my factory Federal 124 gr HST carry ammo. My g26 and M&P Shield have pretty short barrels and do not want to get to snappy but good velocity is a bit of a challenge and RMR recommends around 1100 fps for best results.
 
Yes start with a PLUNK test, that will give you your best OAL, you should be able to find a common OAL that fits all of your firearms.
My last range visit produced;
CALIBER BULLET/WT POWDER LOAD OAL ROUNDS / AVG VELOCITY/ STD DEVIATON/ EXTREME SPREAD /GUN /PRIMER /BRASS/ WEATHER
9MM 124gn RMR MPR BE-86 5.1 1.08 10/1037 13 43 SigP320C Xtrsp Win 91 ptly cldy

There is also a lot of data on in the sticky; https://www.thehighroad.org/index.php?threads/be-86.760289

Leftytsgc
 
wannabefree said:
Good information so far. I will need to do a few dummy test rounds with varying OAL and see just what the longest overall length fits all my guns and go from there.
Click to expand...
I’d suggest biting the bullet and measuring each max COL for each gun. You’ll need to do this for every bullet you reload. There are several threads dedicated to measuring Max and Working COL that are really good. I need to do this for about 10 different 9mms and rather than guess at dummy test round lengths I just use a fired case and spend the time to field strip guns and have a caliper time at it!
My minimum working COL is at 1.120 with the RMR MPR, but most of my barrels aren’t too finicky like the CZ crowd! No offense. Good luck!
 
Different bullet but a small charge ladder
S+B SP, mixed range brass, charges as thrown after setting measure, 5" 9mm1911

String: 4
Date: 3/31/2017
Time: 3:15:43 PM
Grains: 124
Hi Vel: 1112
Low Vel: 1080
Ave Vel: 1093
Ext Spread: 32
Std Dev: 12
RMR 124 1.12 OAL BE86 5.1
Velocity Power Factor Ft/Lbs
1112 137.888 340.434
1099 136.276 332.521
1089 135.036 326.497
1088 134.912 325.898
1080 133.92 321.123

String: 5
Date: 3/31/2017
Time: 3:17:17 PM
Grains: 124
Hi Vel: 1135
Low Vel: 1087
Ave Vel: 1115
Ext Spread: 48
Std Dev: 17
RMR 124 1.12 OAL BE86 5.3
Velocity Power Factor Ft/Lbs
1135 140.74 354.662
1117 138.508 343.502
1118 138.632 344.118
1087 134.788 325.299
1120 138.88 345.35

String: 6
Date: 3/31/2017
Time: 3:18:05 PM
Grains: 124
Hi Vel: 1180
Low Vel: 1143
Ave Vel: 1158
Ext Spread: 37
Std Dev: 14
RMR 124 1.12 OAL BE86 5.5
Velocity Power Factor Ft/Lbs
1180 146.32 383.343
1163 144.212 372.377
1160 143.84 370.458
1143 141.732 359.68
1146 142.104 361.57
 
• The OAL you use is based upon the fit between your bullet and your barrel. The OAL will change for every different bullet you use. So the wide range of OALs you see reported is nothing more than an indication of the wide range of barrel makes they are being used in.

• Agreed. As per other comments I've found the RMR ogive to be rather blunt, which forces a shorter OAL than you may have previously experienced. That's OK, because deep seated bullets actually perform better IMHO.

Good luck with your load testing.
 
Today I spent a little time loading up some dummy rounds with just the bullet @ different OAL's . I found both my Glocks would chamber or plunk all the way out to about 1.125 OAL. My Shield on the other hand needed a shorter OAL of about 1.08. I worked this up by seating progressively deeper until I just got them to seat or plunk the way I felt they should.
So now I am going to load a few rounds with loads starting at about 5.2 gr,5.4gr & 5.6gr of BE 86 powder at around 1.075 OAL and see how they range test. I have a chrony so I will watch that with each of my guns. If I find that the Glocks do not perform well with the shorter OAl needed for the Shield I may have to load some separate batches for them. My hope is to find a happy medium that works well in all of them.
 
Looks like you are making good progress.

I found loads that will work in my subcompact Shield with stiffer recoil spring will often work fine in my Glock fullsize/compact/subcompact.

Look forward to your range report.
 
I just tried the plunk test with all 7 of my 9x19 barrels. I found that 1.100" will pass in them all. 1.090" will be starting for the load work ups.
 
wannabefree said:
Are you using the same RMR 124gr mpr rounds & powder ?
Click to expand...
Yes to the mpr 124 gr. I'm going to work up 3 different powders. Silhouette, CFE-P, and HS-6. At least for now. I plan to chrony these to see what max loads.
I've been wanting to make a 9mm day at the range, here's my excuse. :)
 
Some Silhouette #s
Mixed range brass, S+B Sp 5: 9mm 1911
Charges as thrown after setting measure
String: 5
Date: 8/26/2018
Time: 11:36:55 AM
Grains: 124
Hi Vel: 1059
Low Vel: 1009
Ave Vel: 1036
Ext Spread: 50
Std Dev: 18
5.2 Silhouette124 RMR MPR JHP 1.08
Velocity Power Factor Ft/Lbs
1047 129.828 301.798
1009 125.116 280.289
1031 127.844 292.645
1059 131.316 308.756
1036 128.464 295.49

(was looking to try to make 125 pf above)

.2 more
String: 6
Date: 6/17/2018
Time: 3:44:53 PM
Grains: 124
Hi Vel: 1112
Low Vel: 1076
Ave Vel: 1096
Ext Spread: 36
Std Dev: 16
5.4 Silhouette RMR 124 MPR JHP 1.085
Velocity Power Factor Ft/Lbs
1082 134.168 322.313
1076 133.424 318.748
1110 137.64 339.21
1112 137.888 340.434
1100 136.4 333.126
 
I just opened my first bag of the 124 MPR's and have been experimenting. I noticed the bullet profile is very similar to the factory Remington Ultimate Defense ammo, and copied the 1.125" OAL. They function fine in both a Beretta 92FS and a Hipower Mark II. Remington on left.

IMG_20200412_103202746.jpg
 
Laphroaig said:
124 MPR ... 1.125" OAL. They function fine in both a Beretta 92FS and a Hipower Mark II
Click to expand...
Thanks, that shows the lengths of leade in 92FS and Hi Power barrels. I will have Walkalong add them to the reference thread - https://www.thehighroad.org/index.p...let-max-working-oal-col-for-reference.848462/

Working OAL for RMR 124 gr MPR:
  • 1.150" - SIG P226 Legion SAO
  • 1.125" - Beretta 92FS/Hi Power Mark 2
  • 1.115" - KKM (40-9mm Glock 22)
  • 1.08" - HK VP9/Springfield Armory 1911
  • 1.105" - M&P Shield
  • 1.10" - SIG P320 X-5
  • 1.07" - Taurus PT-111 G2/Canik TP9SFX
  • 1.06" - SIG P938
  • 1.055" - Tactical Kinetics (40-9mm Glock 22)
  • 1.04" - Lone Wolf (40-9mm Glock 23)
  • 1.03" - Bar-Sto (SIG P320 X5)/Taurus PT-809
 
Same exact combo for me. MPR 124 JHP, 5.4 Gr. BE-86 mixed brass and 1.095 for my Glock 19, 34 and Keltek Sub 2K and AR-9. Great combo for me.
I know it is not "scientifically correct" l but I run my expansion comparison tests in water jugs and get great expansion. Not the industry standard ballistic gel, but at least I can see how expansion compares apples to apples to other loads. The MPR's are great bullets.
Be cautious with Alliant load data. I find it runs on the hot side.
 
wannabefree said:
My Shield on the other hand needed a shorter OAL of about 1.08. So now I am going to load a few rounds with loads starting at about 5.2 gr,5.4gr & 5.6gr of BE 86 powder at around 1.075 OAL and see how they range test.
Click to expand...
Now, you need to be cognizant of something called tolerance stack-up. The maximum length for the chamber is 1.080" and you've decided to load at an OAL of 1.075", therefore the difference is 0.005", or about the diameter of roughly 1.5 human hairs. A very, very small clearance.

Your plan will be OK if your loaded rounds only have a negative tolerance. That is, your loading OAL never exceeds 1.075". They may go shorter (to say 1.070"), but never longer than 1.075". IMHO, that would be a very rare occurrence, without continued measurement and testing on your part.

Hope this helps.
 
rfwobbly said:
Now, you need to be cognizant of something called tolerance stack-up. The maximum length for the chamber is 1.080" and you've decided to load at an OAL of 1.075", therefore the difference is 0.005", or about the diameter of roughly 1.5 human hairs. A very, very small clearance.

Your plan will be OK if your loaded rounds only have a negative tolerance. That is, your loading OAL never exceeds 1.075". They may go shorter (to say 1.070"), but never longer than 1.075". IMHO, that would be a very rare occurrence, without continued measurement and testing on your part.

Hope this helps.
Click to expand...

I had the same thought after I wrote my original reply post. To be fair I think my actual contact with tie Shield was closer to 1.085 but when I seated my dummy round to 1.08 there was no sign of contact and it passed the plunk test as per my expectations. I am not sure any slight contact @ 1.08 or slightly greater would actually cause any failure to load or eject anyways but I am no expert.
I have only loaded a few test rounds from 5.0 to 5.6gr so far and all measure right at 1.08 so far. I plan on getting out to the range later this week and testing them and some Extreme 124gr RN bullets also loaded with BE -86 @ 1.135 OAL for comparison. If I have to go to 1.07 to be safe I will but really do not want to seat the RMR MPR's any shorter than I have too as they are really short already.
 
I went up to 5.9 Grs BE-86 with the RMR MPR JHP loaded to fall between 1.105 to 1.100 OAL using CCI-500 primers and my notes say to stop at 5.7 Grs.

1.100 was the longest it would "plunk" in my Colt Series 80. (.38 Super with a 9MM barrel)

5.9 Grs gave relatively little gain in velocity. and 5.7 Grs shot well. I saw no need for 5.9 Grs.
 

Attachments

  • Load # 114 RMR IH 124 gr JHP 5.7 Grs BE-86 - 5 Inch Colt.JPG
    Load # 114 RMR IH 124 gr JHP 5.7 Grs BE-86 - 5 Inch Colt.JPG
    51.5 KB · Views: 13
Status
Not open for further replies.

Similar threads

vaalpens
  • Locked
9mm 124 RMR Jacketed Hollow Point *NEW*
2 3
Replies
66
Views
10K
savagemann
savagemann
B
  • Locked
9mm hollow points
2
Replies
27
Views
1K
LiveLife
LiveLife
D
  • Locked
Rmr 124 mpr short oal Sierra 6th data
Replies
15
Views
753
Duck45lc
D
JO JO
  • Locked
RMR 9mm 124gr rn plated oal
Replies
18
Views
2K
George P
George P
S
  • Locked
load data for sport pistol for short OAL cz 9mm
Replies
17
Views
3K
ray15
ray15
Back
Top