[Carmon S Howard]

I learned today that the Western Powder Reloading Guide 8.0 actually has some 9mm data for RMR bullets. The load data isn’t searchable for word terms, but in my limited scan of of the data I did see some loads using the 115 gr FMJ, 124 gr JHP (I assume that is the MPR), and 135 gr FP. Unfortunately the 124 JHP is loaded to 1.120″ OAL, which won’t chamber in a lot of 9mm barrels, but it does allow for comparison with other 124 grain data.

[Carmon S Howard]

“I am looking for 1100 FPS out of the G26 if possible.”

According to Quickload that should be easy to do without going anywhere near max standard pressure.

“Is there any reason to go shorter with the OAL as long as these are the only 2 guns that I will be shooting this ammo out of?”

In my mind no, but that is entirely up to you.

Be advised that RMR recently started offering a new MPR bullet (the MPR Nuke) that expands at lower velocities. I don’t know that expansion is one of your objectives, but if so those would probably be a better choice from short barrel pistols. I intend to buy 1000 and try them in my pocket pistols that don’t tolerate the hotter loads very well.

[Carmon S Howard]

I’ve loaded quite a few of the 124 gr RMR MPR in 9mm, and I generate data from QuickLoad using the Sierra 125 gr 8125. It is about the same length as the MPR and has a profile that doesn’t accommodate long OALs in most firearms. All my barrels will plunk the MPR at 1.075″, some will go to 1.100″, and a couple will handle 1.125″. Chrono data matches the QL predictions pretty well. VV 3N37 at 6.2 gr and 1.075″ is a standard pressure load and produces over 1150 fps from a 4″ barrel. If the bullet can be seated at the longer 1.125″ length, that charge can be increased by 9% with a corresponding velocity increase of about 50 fps in a 4″ barrel. My goal with these loads is to generate enough velocity for reliable expansion. If that isn’t a priority, I would use enough W231 or AA5 to generate 1050 – 1100 fps and call it a day. 3N37 is a good powder, but it isn’t cheap or widely available at the moment.

Attention to the seating depth is a must for the 9mm. Small changes in OAL will result in big pressure swings. For the loads above, the difference in pressure between 1.075″ and 1.125″ using the same powder charge is about 30% (according to QL), so work up carefully.

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