9mm 147 gr FN RMR Bullet Min OAL

[Crazy Horse]

I purchased 500 9mm 147 grain RMR Match grade FN bullets. There were details in their website about using 1.130 OAL as listed in several reloading manuals.

I first tried reloading to 1.130 using 4.1 grains of CFE Pistol, but the bullets jammed in all except my Canik semi.

I went back and setup 10 rounds at 1.25, 1.20, and 1.15. Well, all of them jammed.

I looked at SAAMI specs and it lists the min OAL at 1.00 for 9mm.

I set the Min OAL to 1.10, but it still didn't pass the plunk test on my Taurus G3.

Before proceeding further, I wanted to inquire if anyone has used the RMR FN 147 match grade 9mm bullets? If so, what OAL did you utilize.

I know that plunk test indicates what will work on a firearm, but I just want to make sure before proceeding.

I still have most of those bullets, and am thinking about getting the 147 grain RN 147 gr 9mm bullets to see if those will cycle better at the 1.130 OAL as indicated in Speer #15 manual.

TIA

 

[fxvr5]

The minimum OAL is whatever is required to fit in your chamber and will feed from your magazine. You might run into issues as you seat them deeper because they are a long bullet and some brass might start to bulge at the base of the bullet. It's only a problem if they won't chamber that way.

Also, as they are seated deeper you'll need to reduce your powder charge to ensure that the pressure is safe.

 

[Blue68f100]

Did you use enough Taper Crimp?

 

[LiveLife]

9mm 147 gr FN RMR Bullet Min OAL

I set the Min OAL to 1.10, but it still didn't pass the plunk test on my Taurus G3.

OAL is dependent on the barrel. Go shorter until they "plunk" into the barrel and feed reliably from the magazine.

Maybe these will help - https://www.thehighroad.org/index.p...col-for-reference.848462/page-2#post-11465109

• Glock 22, KKM 40-9 conversion barrel - RMR 147 gr FP MW: 1.135"
• M&P Shield 9mm, factory barrel - RMR 147 gr FP MW: 1.130"
  
• Glock 22, Tactical Kinetics 40-9 conversion barrel - RMR 147 gr FP MW: 1.075"
• Glock 23, Lone Wolf 40-9 conversion barrel - RMR 147 gr FP MW: 1.065"
  
• SIG P320 X5/Bar-Sto Match 5" Barrel - RMR 147 gr FP MW: 1.04"

How to determine max/working OAL - https://www.thehighroad.org/index.p...-and-discussions.778197/page-10#post-11419509

 

[Crazy Horse]

Thx. Yes I put plenty of taper crimp on the cartridge. The issue is that the round will not chamber all the way. Also once in the chamber, the slide becomes stuck. Which is why I'm going by the plunk test. The strangest thing is that I've never had this much difficulty from a reload affecting so many of my firearms. The only one out of 5 semi's that the round has functioned correctly is my Canik, and that was at the 1.130 OAL. That's why I was thinking that 1.15 - 1.25 would solve the issue. Not so.

I've had other calibers where I had to work on OAL, but never to the point where I had to include reducing a powder charge because of how much deeper the bullet is being seated. At the rate I'm going, the bullet will theoretically be travelling slower than my 45 rounds (4.1 grains of CFE is posted to yield 897 fps)..

I guess it the FP and length of the actual bullet is what makes it most difficult. Which makes me wonder why they call it "Match Winner."

RMR 124gr FMJ RN bullets function great at 1.130 on all my 9mm semi's, I'm thinking that it might be easier to order 147 grain bullets of the same type as the 124gr bullets.

 

[fxvr5]

Which makes me wonder why they call it "Match Winner."

They shoot straight. They make other weights with this same design and they have proven to be quite accurate. I don't have any 9mm data with the 147s, but in the 38 Super they produced a 1.28" 25-shot group at 25 yards at 1132 fps from my gun. That's hard to beat.

 

[Crazy Horse]

So, I seated the bullet until it passed the plunk test. It came down to 1.045-1.050.
Of course, that was with bullets that I had already loaded with 4.1 grains of CFE. With the minimum OAL at 1.000 for the 9mm, the next question should I lower the grains to 3.9 - 4.0. There's plenty of space inside the chamber, but I don't want to create an over pressure situation.

Since I have never worked up a load, how do you know when you've reached a load limit? According to the manual (Speer #15) 4.6 is the maximum charge. I'm usually content going up at most 1/2 way between starting load and max load for any reload.

Thinking about it, with .5 grains below the max recommended, I don't think that seating them to 1.045-1.050 with 4.1 grains would create over pressure.

TIA

 

[Dudedog]

Bear in my as OAL gets shorter you may use less powder but vels will be higher with less powder because of the shorter OAL.

I was aiming for 125 PF loads here 1.075 OAL (testing to get numbers for a shorter OAl for someone on THR) Not as short as you might need to go but maybe some help.
Mixed range brass, S+B SP, charges as thrown after setting measure
5" 9mm 1911

String: 9
Date: 6/17/2018
Time: 2:53:56 PM
Grains: 147
Hi Vel: 887
Low Vel: 832
Ave Vel: 856
Ext Spread: 55
Std Dev: 20
3.8 CFE-P RMR 147 FN FMJ 1.075
Velocity Power Factor Ft/Lbs
849 124.803 235.253
832 122.304 225.926
865 127.155 244.203
887 130.389 256.783
850 124.95 235.807
SD+ES yuck (but small sample)

String: 1
Date: 6/17/2018
Time: 2:55:42 PM
Grains: 147
Hi Vel: 914
Low Vel: 899
Ave Vel: 908
Ext Spread: 15
Std Dev: 6
4.0 CFE-P RMR 147 FN FMJ 1.075
Velocity Power Factor Ft/Lbs
899 132.153 263.778
913 134.211 272.057
914 134.358 272.654
911 133.917 270.867
903 132.741 266.13
SD+ES looking good here

No pressure signs in my pistol with either of these.
(of course in pistol by the time you see any you are WAY over....YMMV)

If I remember correctly Jake from RMR said the 147 match winners don't play well with short chambers.

 

[Howudoingood]

As blue68f100 says, check taper crimp. The 9mm cartridge is tapered, if you don’t crimp enough to remove the flare from the case mouth it won’t chamber correctly.
Good luck.

 

[fxvr5]

Bear in my as OAL gets shorter you may use less powder but vels will be higher with less powder because of the shorter OAL.

Not if you keep chamber pressure the same.

If you shorten the OAL by seating the bullet deeper and reduce the powder charge to keep the pressure the same, the velocity will be less.

 

[lordpaxman]

I first tried reloading to 1.130 using 4.1 grains of CFE Pistol, but the bullets jammed in all except my Canik semi.

Note to self... seems to be a teaching moment here... Whenever you get a new bullet to reload, you need to determine the max and working length in all guns BEFORE reloading any rounds. Regardless of what any published load data has!

Before proceeding further, I wanted to inquire if anyone has used the RMR FN 147 match grade 9mm bullets? If so, what OAL did you utilize.

Yes. Many. 1.120”, but, it was verified in all the barrels and the powder charge was worked up safely to meet a 125PF.
Where did you get your load data from for CFE Pistol? I used Hodgdon reloading online data which lists loads for an XTP bullet, which is a bit different than the RMR FPMW. But I had XTPs and knew their bullet length and could determine seating depth, and then compare the RMR.
You’re correct that most likely the RMR 147gr RN can be loaded longer, and I have one gun that I specifically use them for. Good luck!

 

[Crazy Horse]

I got that data from the speer #15 manual. That bullet looks more like what I'm working with over the hogdon book or site.

When you talk about working up a load, how do you know when you've got the upper limit?

For my barrel 1.120 was still to high of an oal. I'm looking at 1.045-1.050, which is still above the minimum oal as listed in SAAMI, but still less than what is listed in the speer manual of 1.130. this of course is using the plunk test.

 

[fxvr5]

When you talk about working up a load, how do you know when you've got the upper limit?

Depends on your purpose. If you want to keep pressure within SAAMI specs, your upper limit is when the pressure hits the maximum SAAMI pressure limit.

 

[Dudedog]

I didn't say anything about pressure, the point I was attempting to make is unless you are after MAX vels the trade off might be workable.

For fun I had someone run some Quickload numbers (which off course is just a good guess, but a guess)
125gr bullet 4" barrel defaults for HP38

4.2 gr 1.14 23820psi 1006 FPS
4.1gr 1.11 25447psi 1013 FPS
3.9gr 1.08 26051psi 1002 FPS

So yes pressure went up as OAL went down keeping the about the same vel and playing with the powder charge,
So say if you only needed 1000 fps it might be workable. (this example was)
If I needed to go shorter for some reason I would probably go to a slower powder as well, if I wasn't already at the slow side of 9mm powders.


As we know,
OAl goes down pressure goes up given the same charge, as the charge goes down pressure goes down given the same OAL, of course to keep the same vel with a shorter OAL pressure will be higher as was pointed out above in post #10

Yes if you are after the most vel you can get at the lowest pressure longer is better, that's why most of the people loading 9 Major load long....

 

[Crazy Horse]

Yeah, but I don't have the calculation app (quickload) to know how much the pressure is, based on the OAL & gains of powder, to determine if I am below the maximum SAAMI pressure limit.

I saw Dudedog's post, but those FPS numbers are higher than what the Speer manual has, actually for a 147 grain FN bullet, all of the Speer loads posted were at the subsonic level.

That quickload app looks handy, but is expensive. I have always had the fortune of having the posted calculations work on all my firearms. This is the first time a bullet has given me such a challenge.

Some of folks I had met at a competition swore by the 157 grain 9mm bullets, but none of them reload. All their bullets were purchased from a manufacturer. Which is why I decided to give it a try.

Dudedog, when you say load long, do you mean a longer OAL?

 

[Dudedog]

When you talk about working up a load, how do you know when you've got the upper limit?

Hard to tell since most of us have no way to measure pressure. If the gun goes kaboom the wrong way you know you were to high.....the plan is to avoid that at all costs of course.
One way would be flattened primers but if I thought I was at the MAX I would not continue to push until I got flat primers....
A chrono helps but just tells you velocity and in my example above (and as fxvr5 pointed out) you can see that pressures can be higher and result in the same vel.

Dudedog, when you say load long, do you mean a longer OAL

Yes longer OAL.
The numbers above were with a 125gr bullet and as I understand it Quickload is not at it's best with straight wall pistol cartridges. I just had someone run some real quick #s to sort of show what Quickload "guessed" was going on, It's a good well informed guess but still a guess....

You will be able to get more velocity while staying in pressure limits at longer OALs

 

[lordpaxman]

I got that data from the speer #15 manual. That bullet looks more like what I'm working with over the hogdon book or site.

I only have up to the 12th edition and CFE Pistol doesn’t show up there, but I suspect that data was for their GDHP. Hornady’s manual shows an XTP profile at 1.100” and 3.3-4.3gr of CFE Pistol. This is one of the challenges (opportunities my boss used to say) of using a bullet that isn’t in a manual.
Since there’s not an easy way to determine how your bullet will perform relative to the published load’s bullet, I’d start much more towards the minimum load and work up especially if you’re shortening COL from 1.130 to 1.050. That’s a lot of shortening with a very heavy for 9mm bullet.

When you talk about working up a load, how do you know when you've got the upper limit?

My goal is to keep my upper limit below Kaboom. Way below. Like @Dudedog said, the majority of us have no way of measuring pressure, but I do employ a chrono. Most of my 9mm loads have to meet a minimum PF so I need to know the velocity is above a certain minimum. I can also utilize the chrono to see if incremental movements in powder weight correlate to incremental velocity movements - hopefully in a linear way, and hopefully I’m in a near linear region of that pressure curve. That’s a lot of hopeing I know, but the only data I have available. The few loads I’ve pushed towards max published loads had the velocity less than what was predicted but I had no reason to “go faster”. As others have said, reading pressure signs in pistol cartridges is precarious. If I were pushing upper limits more I’d be inclined to get QL just as another data point.

 

[Crazy Horse]

The minimum load for CFE in the Speer manual is 4.1 @ an OAL of 1.130 for the 147gr FP bullet.

Based on Dudedogs estimates. I'm going to create 2 test loads. first load is 1.05 @ 3.9 grains and a second at 1.05 @ 4.0 grains. It'd be nice to have a chrono to measure FPS, but that's not the case. Still, if I can get the FP 147gr bullet to function without jamming, I'd say that is success.

I was looking at purchasing the 147 grain RN bullets over the "Matchwinner," that way OAL would be the same as the 124gr bullets that I know function well in all my 9mm's.

THX

 

[Ramone]

Look for cratering, pierced or flattened primers to determine over pressure. That's the method I've always used.

When in doubt, I compare to known good loads, and examine the primers of suspect loads before and after firing.

I wonder if the Canik has a longer chamber than your other Pistols?

 

[Crazy Horse]

Ramone,

Thanks for the tip.

When doing the plunk test, it definitely passed with a longer OAL. Funny thing though, I would have expected my XDM or S&W wouldn't be too much different.

 

[12Bravo20]

I just looked at Hodgdon's website. This is what they list for a 147Gr bullet and CFE Pistol in 9mm:

147 Gr Hornady XTP, COL - 1.100", Start/min - 3.7Gr , Vel 864, 26,700 PSI , Max - 4.2Gr, Vel 963, 33,000 PSI

 

[rfwobbly]

I purchased 500 9mm 147 grain RMR Match grade FN bullets. There were details in their website about using 1.130 OAL as listed in several reloading manuals.

I first tried reloading to 1.130 using 4.1 grains of CFE Pistol, but the bullets jammed in all except my Canik semi.

I went back and setup 10 rounds at 1.25, 1.20, and 1.15. Well, all of them jammed.

I looked at SAAMI specs and it lists the min OAL at 1.00 for 9mm.

I set the Min OAL to 1.10, but it still didn't pass the plunk test on my Taurus G3.

Before proceeding further, I wanted to inquire if anyone has used the RMR FN 147 match grade 9mm bullets? If so, what OAL did you utilize.

I know that plunk test indicates what will work on a firearm, but I just want to make sure before proceeding.

You are either confused or laboring under a misunderstanding. Let's fix that...

• There are 2 sets of "Limits" which set the Min OAL on any auto pistol cartridge. There is what we might call the Physical Limits set by SAAMI (this you are already know about) and that number for 9x19 Luger is 1.000". Then, usually inside those limits are what we might call the Safety Limits. Typically we choose to set the OAL used in the reloading recipe as the minimum safe OAL. This because going shorter (without goodly amount of calculation or reloading experience) will raise chamber pressure drastically to unsafe levels. So you can simply look in your load manual for this number. Here's a cartoon to represent what I'm saying...



• But 147gr represents a special situation in 9mm Luger which can present a baffling reloading dilemma. Sometimes, due to barrel's machining or the physical dimensions of the bullet's ogive, the reloader is forced use a shorter OAL than planned. Because the 147gr bullet is usually longer than other 0.355" bullets, this forces a deep seating situation. So far, so good... Except that all cartridge cases start to thicken their wall as the side wall approaches the case head. This happens at different places on different brands of brass, but it's there.

If the base of the bullet strikes that interior thickening, then the bullet will physically expand the case dimensions in the middle of the case. When a test cartridge is built and tried in the chamber, the bulge limits entrance, which can then be interpreted as "bad taper crimp" or "excessive OAL", when it is actually excessive bullet seating. Here's a another cartoon to represent what I'm saying...




It's a misinterpretation of this second special situation that I believe is baffling you. If so, then try another brand of brass. In the end, the plain truth may be that those specific bullets cannot be used in your barrel. That doesn't rule out ALL 147gr bullets, only that specific 147gr bullets in that specific brand of brass.

Hope this helps.
.

 

[Crazy Horse]

RTWobbly,

THX. That explains several things.

However, before totally giving up on that bullet,

As you stated - If the base of the bullet strikes that interior thickening, then the bullet will physically expand the case dimensions in the middle of the case.

That being the case, would it mean that the bullet would NOT chamber or pass the plunk test because it expands the case in the middle?

I ask because once I seated the bullet to 1.045 -1.05 the bullet passed the plunk test. After which I was going to go through the next step of reducing the powder load by ..1-2 grains

In this instance, because the bullet requires a shorter OAL (still within SAAMI tolerances) for a number of 9mm Semi's that I tested, I find it difficult to believe that it woudn't work in 4 or the 5 9mm semi's in my inventory.

TIA

 

[LeftyTSGC]

I need to ask one question, are your rounds feeding from your magazine correctly? If so, is it just a chamber problem? Reason I ask is that I have had a couple of firearms, that would not correctly feed certain bullet shapes due to the feed ramp design and shape of projectile. You may be able to pass a plunk test, but if it does not feed correctly then that's a different issue. Just my two cents worth.

 

[Crazy Horse]

LeftyTSGC,

I've had the same type of jam issues with 45acp and LSWC bullets. In this case they feed correctly.

THX.