9mm 124Gr. RMR Nuke and Canik Rival Min. OAL Concerns

[CurryCornDog]

Hello everyone,

I am new here, and yes, I unfortunately have ANOTHER question on Min OAL and a tight-throated barrel. I ask this after scouring the Reloading Manual of Wisdom here on this site for weeks, as well as every thread I can get my hands on- here or elsewhere. Conflicting information has lead me to post this and garner wisdom from the THR collective.

With the standard waiver out of the way, I will float my conundrum as concisely as possible.

Some say find the OAL with plunk testing, start low in charge, and find the butter zone regardless of OAL, within reason. **HOWEVER, others say seating below MIN OAL in 9mm can cause drastic increases in PSI/CUP.**

Min OAL suggested in Lyman 51st and Lee 2nd Edition for 124 gr. JHP XTP is 1.060" with Accurate No.5 powder. The 124 Gr. RMR MPR Nuke (.355) is the bullet in question. Yes, the XTP AND RMR Nukes are apples and oranges. But by everything I can research, it has a similar-yet-not-identical profile as the Hornady XTP listed for that OAL for Accurate No.5 powder in both books. As I understand, finding most similar published data-to-bullet and working from there is the way to go. I cannot find published load data as of yet for the RMR Nuke.

The MAX OAL I have calculated for this specific bullet and my specific barrel is 1.0640". I seat to 1.0620-1.0625". Yet variations in ogive of bullet has me seating dummies as low as 1.057" to properly plunk, twist, and drop out of chamber cleanly. I am using a crimp tight enough on every round to create a 0.375" case fitment around the bullet and removing the bell from expanding. The bullet is seated properly snug by press-testing and measuring no movement from set OAL. For those shorter rounds, being under listed Min OAL has me concerned, though i understand tests in books are not done with standard barrels.

Should I set these aside for a more forgiving chamber/firearm and try another bullet? Or go ahead with minimum powder loads and give it a try to work it up?*

GEAR (if relevant):
-Press: Lyman All American 8
-Dies: Lee 4 die set (FL sizing/deprime, powder-thru-expander, bullet seat, and FCD)
-Brass: Blazer once-fired
-Powder: Accurate No.5 (Chosen beforehand for its seemingly large and forgiving load range).
-Bullet: RMR MPR Nuke 124 gr.
-Primer: ZSR (Hey man, it's all they had. They go bang.)

^If youre still reading after that, thank you. That is my question, and any comments and thoughts are welcome.

For those still reading, I am not one to take risks, and only want two piles: a pile of 130 PF for IDPA, and a hotter pile for self-defense. Yes this bullet is unnecessary/overkill/too expensive for IDPA. I chose this bullet to both satisfy my want to both compete and load perhaps a bit hotter for stockpiling defensive rounds should the unlikely-yet-possible scenario come about where everything turns to crap. I'd rather just mono-crop the projectiles to keep things simple and only have to change powder loads as necessary. That was the idea, anyway...until I saw how tight these damn things are in my chamber.

I appreciate everyone patient enough to read through, and if you do respond, thank you for taking the time. I will try to respond as soon as I can if my question is met with another, or hell, just to say thanks for your time.

For those curious, factory rounds I have tried all went bang, ranging from Federal HST 124 gr. (1.0995"-1.1000" OAL. Much more conaical shape, thus of course a different ogive) to Blazer brass 124 gr.

 

[JCSC]

It doesn’t matter if they are only 1.00 long. Drop back on the charge and work up. Worst case it doesn’t cycle properly and you have to clear barrel.

much better than having it frag and blow off a hand.

 

[CurryCornDog]

It doesn’t matter if they are only 1.00 long. Drop back on the charge and work up. Worst case it doesn’t cycle properly and you have to clear barrel.

much better than having it frag and blow off a hand.

So basically you're saying as long as it plunks properly, it would be alright to start at minimum charge and work up from there? That is what has been said, but usually to loads not under Min OAL. Either way, thank you for taking the time to respond!

**EDIT: I will say everything I have mocked up so far has chambered just fine, and I'm confident will go boom. Just want it to go boom in the fun hole-through-paper way and not the no-more-hand way.

 

[nettlle]

If the cartridge dimensions and powder charge are within that specified by the reloading manual(s) and they feed and eject shoot them. If you are not willing to take risks then reloading may not be your cup of tea. There is no perfect manual or no perfect website than can describe every type of bullet, primer, brass, powder, for every gun and shooter. And I am a big fan of RMR bullets.

 

[CurryCornDog]

If the cartridge dimensions and powder charge are within that specified by the reloading manual(s) and they feed and eject shoot them. If you are not willing to take risks then reloading may not be your cup of tea. There is no perfect manual or no perfect website than can describe every type of bullet, primer, brass, powder, for every gun and shooter. And I am a big fan of RMR bullets.

Thanks for the reply.

I said the risk thing weirdly. I meant I'm not looking to throw in a full max charge off the rip. If starting low seems like a good idea, even if under Min OAL, then I'm happy to do so. I just haven't found a clear answer or consesus, is all.

 

[Docendo Discimus]

1.0620-1.0625". Yet variations in ogive of bullet has me seating dummies as low as 1.057

Unless you are near max that .005 variation isn't going to give you pressure problems. Bullet weight differences, brass capacity differences, powder lot differences, ambient temp, etc, etc. all come into play also. Pick an AOL that cycles well and pick a starting charge and go from there.

 

[GeoDudeFlorida]

Hello everyone,

I am new here, and yes, I unfortunately have ANOTHER question on Min OAL and a tight-throated barrel. I ask this after scouring the Reloading Manual of Wisdom here on this site for weeks, as well as every thread I can get my hands on- here or elsewhere. Conflicting information has lead me to post this and garner wisdom from the THR collective.

With the standard waiver out of the way, I will float my conundrum as concisely as possible.

Some say find the OAL with plunk testing, start low in charge, and find the butter zone regardless of OAL, within reason. **HOWEVER, others say seating below MIN OAL in 9mm can cause drastic increases in PSI/CUP.**

Min OAL suggested in Lyman 51st and Lee 2nd Edition for 124 gr. JHP XTP is 1.060" with Accurate No.5 powder. The 124 Gr. RMR MPR Nuke (.355) is the bullet in question. Yes, the XTP AND RMR Nukes are apples and oranges. But by everything I can research, it has a similar-yet-not-identical profile as the Hornady XTP listed for that OAL for Accurate No.5 powder in both books. As I understand, finding most similar published data-to-bullet and working from there is the way to go. I cannot find published load data as of yet for the RMR Nuke.

The MAX OAL I have calculated for this specific bullet and my specific barrel is 1.0640". I seat to 1.0620-1.0625". Yet variations in ogive of bullet has me seating dummies as low as 1.057" to properly plunk, twist, and drop out of chamber cleanly. I am using a crimp tight enough on every round to create a 0.375" case fitment around the bullet and removing the bell from expanding. The bullet is seated properly snug by press-testing and measuring no movement from set OAL. For those shorter rounds, being under listed Min OAL has me concerned, though i understand tests in books are not done with standard barrels.

Should I set these aside for a more forgiving chamber/firearm and try another bullet? Or go ahead with minimum powder loads and give it a try to work it up?*

GEAR (if relevant):
-Press: Lyman All American 8
-Dies: Lee 4 die set (FL sizing/deprime, powder-thru-expander, bullet seat, and FCD)
-Brass: Blazer once-fired
-Powder: Accurate No.5 (Chosen beforehand for its seemingly large and forgiving load range).
-Bullet: RMR MPR Nuke 124 gr.
-Primer: ZSR (Hey man, it's all they had. They go bang.)

^If youre still reading after that, thank you. That is my question, and any comments and thoughts are welcome.

For those still reading, I am not one to take risks, and only want two piles: a pile of 130 PF for IDPA, and a hotter pile for self-defense. Yes this bullet is unnecessary/overkill/too expensive for IDPA. I chose this bullet to both satisfy my want to both compete and load perhaps a bit hotter for stockpiling defensive rounds should the unlikely-yet-possible scenario come about where everything turns to crap. I'd rather just mono-crop the projectiles to keep things simple and only have to change powder loads as necessary. That was the idea, anyway...until I saw how tight these damn things are in my chamber.

I appreciate everyone patient enough to read through, and if you do respond, thank you for taking the time. I will try to respond as soon as I can if my question is met with another, or hell, just to say thanks for your time.

For those curious, factory rounds I have tried all went bang, ranging from Federal HST 124 gr. (1.0995"-1.1000" OAL. Much more conaical shape, thus of course a different ogive) to Blazer brass 124 gr.

Well, there’s two pieces of good news here: First, you are smart enough to ask and that means you’re thinking. Second, there’s a whole bunch of safety margin built into the No.5 loading data. So that’s a definite plus.
The overall length is a way to approximate the seating depth. The seating depth is really what makes the difference in pressure, for the most part. Jamming the lands will also raise pressure but that’s a different story. The way to tell if you’re outside the safety zone is if you’re seated deep enough to compress the load of a powder that shouldn’t be compressed. And that’s the other good news: No.5 can be compressed but at 1.05” you’re not close to a compressed load. The math says you’re still plenty safe at the middle load.

 

[CurryCornDog]

Unless you are near max that .005 variation isn't going to give you pressure problems. Bullet weight differences, brass capacity differences, powder lot differences, ambient temp, etc, etc. all come into play also. Pick an AOL that cycles well and pick a starting charge and go from there.

That is the type of information I am looking for. Not confirmation bias, but knowing that this small of a variance is, under a cautious hand, forgiving enough to work with. Thank you for taking the time to respond!

 

[nettlle]

Understandably you shouldn't go full charge right out of the gate. Minimum reloading charge is a good place to start. On semi-auto handguns there is a good possibility that the recommended COAL could effect feeding. Your final COAL may or may not fall within the reloading manual specifications. Reloading isn't plug and play. There is a little a little well thought out experimentation involved. And with this there is some risk.

 

[CurryCornDog]

Well, there’s two pieces of good news here: First, you are smart enough to ask and that means you’re thinking. Second, there’s a whole bunch of safety margin built into the No.5 loading data. So that’s a definite plus.
The overall length is a way to approximate the seating depth. The seating depth is really what makes the difference in pressure, for the most part. Jamming the lands will also raise pressure but that’s a different story. The way to tell if you’re outside the safety zone is if you’re seated deep enough to compress the load of a powder that shouldn’t be compressed. And that’s the other good news: No.5 can be compressed but at 1.05” you’re not close to a compressed load. The math says you’re still plenty safe at the middle load.

Much appreciated! That is exactly the kind of info I'm looking for. Safety margins! Lame to some, but highly necessary. You rock. Looks like I'll be starting low and beginning a powder work-up here shortly. Thanks again, I feel a bit better about starting slow with this particular cartridge combo.

 

[CurryCornDog]

Understandably you shouldn't go full charge right out of the gate. Minimum reloading charge is a good place to start. On semi-auto handguns there is a good possibility that the recommended COAL could effect feeding. Your final COAL may or may not fall within the reloading manual specifications. Reloading isn't plug and play. There is a little a little well thought out experimentation involved. And with this there is some risk.

Understandable. I got into reloading for both the minutia as I'm a tinkerer, and of course being able to go to the range or to a match with a bit of pride knowing exactly what I have in my mags. And that's why I came here, to learn without ego from those who've been at it, likely longer than I've been alive

Thanks again, and I'll eventually report back with results when I find a day to get some range time in.

 

[Dudedog]

Western load data from a few years back lists data for a RMR JHP. (but does not specify MPR but MPRs were the RMR HP when the data was released) I haven't used any of the Nukes yet but I believe they are the MPR with an improved HP design.
Western has +P data as well.



9mm +P Data



Of course they are showing a Longer OAL than you can use.
Remember what matters pressure wise is really how much of the bullet is in the case, so for example a bullet with more "nose" might have a longer OAl and be taking up the same amount of space in the case as a bullet with less "nose" at a shorter OAL.
I have loaded a lot of the MPRs, but none with AA#5

Do you have a chrono to check your loads to verify you are making PF?
Of course a chrono won't tell you pressure, but since there is no such thing as a free lunch, more vel = more pressure.
At the longer OAL standard pressure is #5 5.5 to 6.1gr
+P is 6.1 to 6.5,
so it appears you have some wiggle room but shorter OALs are less forgiving.
(and of course by the time you see pressure signs in 9mm you are way over)

My Lyman 50 shows the XTP 124 @ 1.06 5.4 to 6.1 AA5, Sierra 125 JHP @ 1.075 5.4 to 6.1 as well.


If it was me I would start with about 5.2 to 5.3gr (.2 or .3 less than the start charge due to your shorter OAL) chrono if you can to see where you are at and work up from there.
edit: I wouldn't load to many there until I verified function.

If you work up to get to about 1070-1080fps I would call that MAX.

I don't have any data for AA5 but I do have some for WSF at a couple OALs which might be of some help showing how a shorter OAL changed vel.

Note: I am not saying AA5 = WSF just some numbers for WSF which is a little faster burn speed wise
5" 1911, S+B SP, mixed range brass, charges as thrown after setting measure
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 4.5 WSF 1.08
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

( I use 4.6gr of WSF for my match load for USPSA, gives me about 128/129 PF)

String: 6
Date: 9/17/2017
Time: 11:30:58 AM
Grains: 124
Hi Vel: 1067
Low Vel: 1005
Ave Vel: 1041
Ext Spread: 62
Std Dev: 24
RMR MPR JHP 4.55 (between 4.5 and 4.6)WSF 1.065
Velocity Power Factor Ft/Lbs
1034 128.216 294.35
1005 124.62 278.071 (light charge??)
1043 129.332 299.497
1059 131.316 308.756
1067 132.308 313.438

So here the shorter OAL upped the average vel 20fps which of course means it upped the pressure

String: 7
Date: 9/17/2017
Time: 11:32:12 AM
Grains: 124
Hi Vel: 1122
Low Vel: 1092
Ave Vel: 1106
Ext Spread: 30
Std Dev: 12
RMR MPR JHP 4.8 WSF 1.065
Velocity Power Factor Ft/Lbs
1095 135.78 330.105
1114 138.136 341.66
1122 139.128 346.584
1108 137.392 337.989
1092 135.408 328.298

I would guess the one below was getting in to +P pressures but don't know that,
I called 5.0gr my MAX and quit there, .3 less than the MAX with a longer OAL list by Hodgdon. (higher vel to)

String: 8
Date: 9/17/2017
Time: 11:33:50 AM
Grains: 124
Hi Vel: 1157
Low Vel: 1121
Ave Vel: 1139
Ext Spread: 36
Std Dev: 15
RMR MPR JHP 5.0 WSF 1.065
Velocity Power Factor Ft/Lbs
1153 142.972 366.001
1132 140.368 352.79
1157 143.468 368.545
1135 140.74 354.662
1121 139.004 345.967

Hodgdon data for WSF with a different bullet and longer OAL
125 FMJ Winchester WSF 0.355 1.16 4.7 1015 27,700 PSI 5.3 1115 32,700 PSI

Hope this is some help.
BTW welcome to THR lots of great people here.

 

[CurryCornDog]

Western load data from a few years back lists data for a RMR JHP. (but does not specify MPR)I haven't used any of the Nukes yet but I believe they are the MPR with an improved HP design.
Western has +P data as well.

View attachment 1137946

9mm +P Data

View attachment 1137947

Of course they are showing a Longer OAL than you can use.
Remember what matters pressure wise is really how much of the bullet is in the case, so for example a bullet with more "nose" might have a longer OAl and be taking up the same amount of space in the case as a bullet with less "nose" at a shorter OAL.
I have loaded a lot of the MPRs, but not with AA#5

Do you have a chrono to check your loads to verify you are making PF?
Of course a chrono won't tell you pressure, but since there is no such thing as a free lunch, more vel = more pressure.s
pressures. (again just guessing pressure wise)
At the longer OAL standard pressure is #5 5.5 to 6.1gr
+P is 6.1 to 6.5,
so it appears you have some wiggle room but shorter OALs are less forgiving.
(and of course by the time you see pressure signs in 9mm you are way over)

My Lyman 50 shows the XTP 124 @ 1.06 5.4 to 6.1 AA5, Sierra 125 JHP @ 1.075 5.4 to 6.1 as well.


If it was me I would start with about 5.2 to 5.3gr (.2 or .3 less than the start charge due to your shorter OAL) chrono if you can to see where you are at and work up from there.

If you work up to get to about 1070-1080fps I would call that MAX.

I don't have any data for AA5 but I do have some for WSF at a couple OALs which might be of some help

Note: I am not saying AA5 = WSF just some numbers for WSF which is a litter faster burn speed wise but close

5" 1911, S+B SP, mixed range brass, charges as thrown after setting measure
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 4.5 WSF 1.08
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

(The I use 4.6gr of WSF for my match load for USPSA, gives me about 128/129 PF)

String: 6
Date: 9/17/2017
Time: 11:30:58 AM
Grains: 124
Hi Vel: 1067
Low Vel: 1005
Ave Vel: 1041
Ext Spread: 62
Std Dev: 24
RMR MPR JHP 4.55 (between 4.5 and 4.6)WSF 1.065
Velocity Power Factor Ft/Lbs
1034 128.216 294.35
1005 124.62 278.071
1043 129.332 299.497
1059 131.316 308.756
1067 132.308 313.438

So here the shorter OAL upped the average vel 20fps which of course means it upped the pressure

String: 7
Date: 9/17/2017
Time: 11:32:12 AM
Grains: 124
Hi Vel: 1122
Low Vel: 1092
Ave Vel: 1106
Ext Spread: 30
Std Dev: 12
RMR MPR JHP 4.8 WSF 1.065
Velocity Power Factor Ft/Lbs
1095 135.78 330.105
1114 138.136 341.66
1122 139.128 346.584
1108 137.392 337.989
1092 135.408 328.298

I would guess the one below was getting in to +P pressures but don't know that

String: 8
Date: 9/17/2017
Time: 11:33:50 AM
Grains: 124
Hi Vel: 1157
Low Vel: 1121
Ave Vel: 1139
Ext Spread: 36
Std Dev: 15
RMR MPR JHP 5.0 WSF 1.065
Velocity Power Factor Ft/Lbs
1153 142.972 366.001
1132 140.368 352.79
1157 143.468 368.545
1135 140.74 354.662
1121 139.004 345.967

Hodgdon data for WSF with a different bullet and longer OAL
125 FMJ Winchester WSF 0.355 1.16 4.7 1015 27,700 PSI 5.3 1115 32,700 PSI

Damn. That was no joke of a response, my guy. Thank you! That gives me a lot to prune over. Also, with everyone else's responses so far, gives me a good amount of confidence to start low and work up sloooowly, which was my plan anyways. I see many postulating a low charge and cautious hand will allow me to not only create a usable round, but also (happily) mean less is more. I'm cheap in many respects, so less powder used is pennies saved.

I do not yet have a chrono, but it is on the list to buy soon. Baby steps, got to make sure I can even get this idea off the ground first! Of course it would be nice to know my power factor rather than going in with hopes and crossed toes. That'll come soon enough.

 

[Dudedog]

Chronos are handy to have.
If you check with some people at your IDPA match there might be someone who will let you use theirs if you explain you want to make sure you are making PF.
I have a Competition Electronics Prochrono, they used to be about $120 but are probably $150 or more by now. Quite happy with it.
One thing about CE is if you shoot your chrono and kill it they will replace/repair it for 1/2 price.

(Rifles with scopes above the bore line can be death to chronos up close)
Old joke is there are two kinds of chrono users, those who have shot their chrono and those that will.

Seems like lead poisoning is a common cause of chrono death
(mine is still alive but various people here have killed theirs)

 

[LiveLife]

Welcome to THR.

question on Min OAL and a tight-throated barrel ... 124 Gr. RMR MPR Nuke ... Accurate No.5 ... cannot find published load data as of yet for the RMR Nuke ... MAX OAL ... calculated ... 1.0640" ... I seat to 1.0620-1.0625" ... seating dummies as low as 1.057" to properly plunk, twist, and drop out of chamber cleanly

Especially for barrels with short leade, focus should be on Max OAL from the plunk test using the barrel then determining the Working OAL by feeding dummy rounds from the magazine without riding the slide before conducting initial powder work up (And making necessary adjustment to start/max charges if Working OAL is shorter than published OAL):

1. First determine the Max OAL for the barrel using the "Plunk Test" - https://www.shootingtimes.com/editorial/reloading-tips-the-plunk-test/99389
2. Next, determine the Working OAL by feeding dummy rounds (No powder, no primer) loaded to Max OAL from the magazine without riding the slide. Often Max OAL can be used as Working OAL to reliably feed rounds from the magazine but if they don't, incrementally decrease the OAL by .005" until they do.
3. Then using the Working OAL, conduct your initial powder work up. If your Working OAL is longer than published load data for same weight/nose profile bullet, you do not need to adjust the start/max charges. If your Working OAL is shorter than published, consider reducing your start/max charges by .2 to .3 gr.
4. For greater accuracy or developing match loads, if the powder charge that produced smallest groups is not at max charge, incrementally decrease the OAL by .005". If shorter OAL produces smaller groups, use shorter OAL.

FYI from reference thread "Barrel vs Bullet Max/Working OAL/COL" - https://www.thehighroad.org/index.p...col-for-reference.848462/page-2#post-12249361

• Canik TP9SFX - RMR 124 gr JHP MPR: Max OAL 1.090" - Working OAL 1.070"

And some more Max/Working OALs with match/aftermarket barrels that have shorter leade:

• Glock 22/KKM 40-9mm barrel - RMR 124 gr JHP MPR: 1.115"
• Glock 22/Tactical Kinetics 40-9mm barrel - RMR 124 gr JHP MPR: 1.055"
• Glock 22/Lone Wolf 40-9mm barrel - RMR 124 gr JHP MPR: 1.040"

As to load data, Hodgdon has RMR JHP load data for No. 5 along with other JHPs - https://www.hodgdonreloading.com/reloading-data-center

• 9mm 124 gr Remington GS No. 5 COL 1.145" Start 5.5 gr (970 fps) - Max 6.5 gr (1,127 fps)
• 9mm 124 gr RMR JHP No. 5 COL 1.120" Start 5.5 gr (989 fps) - Max 6.1 gr (1,076 fps)
• 9mm 124 gr Speer GDHP No. 5 COL 1.105" Start 5.1 gr (924 fps) - Max 6.0 gr (1,067 fps)
• 9mm 124 gr Hornady XTP No. 5 COL 1.060" Start 4.8 gr (905 fps) - Max 5.7 gr (1,075 fps)
• 9mm 125 gr Sierra JHP No. 5 COL 1.035" Start 4.6 gr (899 fps) - Max 5.4 gr (1,027 fps)

So depending on the Working OAL determined, I would reference the listing of start/max charges and adjust accordingly.

I am using a crimp tight enough on every round to create a 0.375" case fitment around the bullet and removing the bell from expanding. The bullet is seated properly snug by press-testing

You do not need a "tight crimp" rather just return flare back flat on bullet base. Since average case wall thickness at case mouth is around .011", I usually add .022" to the bullet diameter to determine the "taper crimp" amount.

So for .355" sized RMR JHP/MPR,

.355" + .022" = .377" (This is measurement at case mouth)
​

As to testing for neck tension and bullet setback, I used to push on the bullet nose against the bench top but found using dummy rounds and feeding/chambering from magazine better duplicated the impact forces of slide slamming round against the feed ramp - https://www.thehighroad.org/index.php?threads/380-acp-fyi.914151/#post-12503874

 

[CurryCornDog]

Welcome to THR.


Especially for barrels with short leade, focus should be on Max OAL from the plunk test using the barrel then determining the Working OAL by feeding dummy rounds from the magazine without riding the slide before conducting initial powder work up (And making necessary adjustment to start/max charges if Working OAL is shorter than published OAL):

1. First determine the Max OAL for the barrel using the "Plunk Test" - https://www.shootingtimes.com/editorial/reloading-tips-the-plunk-test/99389
2. Next, determine the Working OAL by feeding dummy rounds (No powder, no primer) loaded to Max OAL from the magazine without riding the slide. Often Max OAL can be used as Working OAL to reliably feed rounds from the magazine but if they don't, incrementally decrease the OAL by .005" until they do.
3. Then using the Working OAL, conduct your initial powder work up. If your Working OAL is longer than published load data for same weight/nose profile bullet, you do not need to adjust the start/max charges. If your Working OAL is shorter than published, consider reducing your start/max charges by .2 to .3 gr.
4. For greater accuracy or developing match loads, if the powder charge that produced smallest groups is not at max charge, incrementally decrease the OAL by .005". If shorter OAL produces smaller groups, use shorter OAL.

FYI from reference thread "Barrel vs Bullet Max/Working OAL/COL" - https://www.thehighroad.org/index.p...col-for-reference.848462/page-2#post-12249361

• Canik TP9SFX - RMR 124 gr JHP MPR: Max OAL 1.090" - Working OAL 1.070"

And some more Max/Working OALs with match/aftermarket barrels that have shorter leade:

• Glock 22/KKM 40-9mm barrel - RMR 124 gr JHP MPR: 1.115"
• Glock 22/Tactical Kinetics 40-9mm barrel - RMR 124 gr JHP MPR: 1.055"
• Glock 22/Lone Wolf 40-9mm barrel - RMR 124 gr JHP MPR: 1.040"

As to load data, Hodgdon has RMR JHP load data for No. 5 along with other JHPs - https://www.hodgdonreloading.com/reloading-data-center

• 9mm 124 gr Remington GS No. 5 COL 1.145" Start 5.5 gr (970 fps) - Max 6.5 gr (1,127 fps)
• 9mm 124 gr RMR JHP No. 5 COL 1.120" Start 5.5 gr (989 fps) - Max 6.1 gr (1,076 fps)
• 9mm 124 gr Speer GDHP No. 5 COL 1.105" Start 5.1 gr (924 fps) - Max 6.0 gr (1,067 fps)
• 9mm 124 gr Hornady XTP No. 5 COL 1.060" Start 4.8 gr (905 fps) - Max 5.7 gr (1,075 fps)
• 9mm 125 gr Sierra JHP No. 5 COL 1.035" Start 4.6 gr (899 fps) - Max 5.4 gr (1,027 fps)

So depending on the Working OAL determined, I would reference the listing of start/max charges and adjust accordingly.


You do not need a "tight crimp" rather just return flare back flat on bullet base. Since average case wall thickness at case mouth is around .011", I usually add .022" to the bullet diameter to determine the "taper crimp" amount.

So for .355" sized RMR JHP/MPR,

.355" + .022" = .377" (This is measurement at case mouth)
​

As to testing for neck tension and bullet setback, I used to push on the bullet nose against the bench top but found using dummy rounds and feeding/chambering from magazine better duplicated the impact forces of slide slamming round against the feed ramp - https://www.thehighroad.org/index.php?threads/380-acp-fyi.914151/#post-12503874

Wow, some of those OALs on those barrels are insane! Seeing that definitely makes me feel better knowing I'm not committing some atrocity by just making sure it fits and then start low and slow. That is quite reassuring. I'll be reading through those articles you listed. Thank you for replying and for the warm welcome.

EDIT: as for the crimp, that is also where I found the round to chamber and plunk properly. Too loose introduced hangups, I'm guessing it wasn't agreeing with the chamber if it was too loose.

 

[Jim Watson]

RMR has their own forum. Check in at
https://www.rmrbullets.com/forums/forum/reloading-database/

 

[CurryCornDog]

RMR has their own forum. Check in at
https://www.rmrbullets.com/forums/forum/reloading-database/

Awesome! Thanks for the heads up. Checking it out now!

 

[CurryCornDog]

Welcome to THR.


Especially for barrels with short leade, focus should be on Max OAL from the plunk test using the barrel then determining the Working OAL by feeding dummy rounds from the magazine without riding the slide before conducting initial powder work up (And making necessary adjustment to start/max charges if Working OAL is shorter than published OAL):

1. First determine the Max OAL for the barrel using the "Plunk Test" - https://www.shootingtimes.com/editorial/reloading-tips-the-plunk-test/99389
2. Next, determine the Working OAL by feeding dummy rounds (No powder, no primer) loaded to Max OAL from the magazine without riding the slide. Often Max OAL can be used as Working OAL to reliably feed rounds from the magazine but if they don't, incrementally decrease the OAL by .005" until they do.
3. Then using the Working OAL, conduct your initial powder work up. If your Working OAL is longer than published load data for same weight/nose profile bullet, you do not need to adjust the start/max charges. If your Working OAL is shorter than published, consider reducing your start/max charges by .2 to .3 gr.
4. For greater accuracy or developing match loads, if the powder charge that produced smallest groups is not at max charge, incrementally decrease the OAL by .005". If shorter OAL produces smaller groups, use shorter OAL.

FYI from reference thread "Barrel vs Bullet Max/Working OAL/COL" - https://www.thehighroad.org/index.p...col-for-reference.848462/page-2#post-12249361

• Canik TP9SFX - RMR 124 gr JHP MPR: Max OAL 1.090" - Working OAL 1.070"

And some more Max/Working OALs with match/aftermarket barrels that have shorter leade:

• Glock 22/KKM 40-9mm barrel - RMR 124 gr JHP MPR: 1.115"
• Glock 22/Tactical Kinetics 40-9mm barrel - RMR 124 gr JHP MPR: 1.055"
• Glock 22/Lone Wolf 40-9mm barrel - RMR 124 gr JHP MPR: 1.040"

As to load data, Hodgdon has RMR JHP load data for No. 5 along with other JHPs - https://www.hodgdonreloading.com/reloading-data-center

• 9mm 124 gr Remington GS No. 5 COL 1.145" Start 5.5 gr (970 fps) - Max 6.5 gr (1,127 fps)
• 9mm 124 gr RMR JHP No. 5 COL 1.120" Start 5.5 gr (989 fps) - Max 6.1 gr (1,076 fps)
• 9mm 124 gr Speer GDHP No. 5 COL 1.105" Start 5.1 gr (924 fps) - Max 6.0 gr (1,067 fps)
• 9mm 124 gr Hornady XTP No. 5 COL 1.060" Start 4.8 gr (905 fps) - Max 5.7 gr (1,075 fps)
• 9mm 125 gr Sierra JHP No. 5 COL 1.035" Start 4.6 gr (899 fps) - Max 5.4 gr (1,027 fps)

So depending on the Working OAL determined, I would reference the listing of start/max charges and adjust accordingly.


You do not need a "tight crimp" rather just return flare back flat on bullet base. Since average case wall thickness at case mouth is around .011", I usually add .022" to the bullet diameter to determine the "taper crimp" amount.

So for .355" sized RMR JHP/MPR,

.355" + .022" = .377" (This is measurement at case mouth)
​

As to testing for neck tension and bullet setback, I used to push on the bullet nose against the bench top but found using dummy rounds and feeding/chambering from magazine better duplicated the impact forces of slide slamming round against the feed ramp - https://www.thehighroad.org/index.php?threads/380-acp-fyi.914151/#post-12503874

You know? It's interesting Hodgdon has them at a 1.120 OAL and an XTP at 1.060, especially considering the XTP is about thirty-thou longer than the RMR Nukes (.573-.577 compared to ~.544-.546 in my batch) with the same diameter. So that equates to about a .030 extra powder chamber difference in my favor with the RMR Nukes. I'm actually safer at the same OAL than the regarded safe XTP distance. Dunno why I didn't look that up before.


It's looking more and more like this is going to be a perfectly safe load to use and that I'm worrying about nothing much at all.

 

[LiveLife]

I am not one to take risks, and only want two piles: a pile of 130 PF for IDPA, and a hotter pile for self-defense.

It's looking more and more like this is going to be a perfectly safe load to use and that I'm worrying about nothing much at all.

For defensive rounds loaded near max/max load data and match rounds that must be more accurate, I would use headstamp and casewall thickness that didn't produce any bullet setback - https://www.thehighroad.org/index.p...neck-tension-and-bullet-setback.830072/page-4

(As to loading own defensive rounds, we had this discussion many times before on THR and while there nothing wrong with loading own defensive rounds, I prefer to use factory ammunition for SD/HD as I rather hand police/LE couple boxes of factory ammunition for evidence instead of them taking my entire reloading equipment/components for duration of trial in case they needed to duplicate the defensive load )

As to powder selection, in general slower burning powders produce optimal accuracy at near max/max load data and for 130 "minor" power factor loads, faster burning powders around Titegroup/N320/Sport Pistol burn rate may produce more efficient powder burn and chamber pressure build for accuracy than No. 5 (Compare groupings of powders by burn rate half way down the linked post) - https://www.thehighroad.org/index.p...-and-discussions.778197/page-11#post-12415502

FYI, these are most popular powders used for USPSA minor PF (130) loads - https://www.thehighroad.org/index.p...-and-discussions.778197/page-11#post-12415502

• Production (9mm) - Titegroup 35%, N320 23%, Sport Pistol 16%

For decades, I not only used WSF for USPSA major power factor loads but also for "duplicate" defensive loads using same Speer Gold Dot HP/Remington Golden Saber JHP bullets/projectiles for training drill "practice" due to higher muzzle velocities and accuracy WSF produced but when Alliant released BE-86, switched from WSF as BE-86 produced higher velocities and greater accuracy/smaller groups (Rumbling is BE-86 is OEM powder used for decades to load various factory premium rounds like Speer Gold Dot/Federal HST and other manufacturers finally released for reloading as "canister" powder) - https://reloadingdata.speer.com/downloads/speer/reloading-pdfs/handgun/9mm_Luger__124_rev1.pdf

• 9mm 124 gr Speer GDHP BE-86 COL 1.120" Start 5.4 gr (1124 fps) - Max 6.0 gr (1199 fps)
• 9mm 124 gr Speer GDHP No. 5 COL 1.120" Start 5.7 gr (963 fps) - Max 6.4 gr (1069 fps)

And Hodgdon load data (BTW, HAP is same bullet as XTP but without expansion cuts for more reliable feeding for match shooting) - https://www.hodgdonreloading.com/reloading-data-center

• 9mm 125 gr Hornady HAP WSF COL 1.069" Start 4.3 gr (991 fps) - Max 5.0 gr (1,083 fps)
• 9mm 124 gr Hornady XTP No. 5 COL 1.060" Start 4.8 gr (905 fps) - Max 5.7 gr (1,075 fps)

Additional issues for bullet setback are affect on chamber pressure and accuracy. As illustrated by OAL/COL change (bullet setback) vs pressure chart below, even small change of .005" can increase pressure by around 4,000 PSI for 9mm and 8,000 PSI for 40S&W using Ramshot Zip that has comparable burn rate of W231/HP-38.

So if you are at max charge and experience significant bullet setback, you could be over published max pressure. And if your "chambered OAL variance"/bullet setback is inconsistent, then your accuracy will likely be affected. Especially for defensive rounds that are loaded at higher muzzle velocities using near max/max charges and match rounds that must produce smallest groups, I prefer to use bullet/case wall thickness combination that does not produce any bullet setback (And preferably once-fired brass that are more malleable than work hardened brass that's been reloaded multiple times).

And keep in mind that cases can get shorter as it is repeatedly reloaded and shorter resized cases that are work hardened (think brass spring back) will apply less neck tension on bullet base than longer resized cases with less number of reloading (think malleability of brass). So for maximum neck tension and greater accuracy, use longest resized cases sorted by headstamp (that won't produce bullet setback) that are once-fired or have least amount of reloadings.

BTW, results from bullet setback testing from myth busting thread using different diameter bullets - https://www.thehighroad.org/index.p...-and-discussions.778197/page-11#post-12503881

 

[lordpaxman]

@CurryCornDog, welcome to THR. Lots of great advice here on the forums!

HOWEVER, others say seating below MIN OAL in 9mm can cause drastic increases in PSI/CUP.

It can, depending on a number of factors including how much further seating depth, the powder, and the bullet technology. I treat the faster powders as being more sensitive than the slower powders, and jacketed bullets more than lead/coated bullets. If you were saying you’re using Titegroup, then, that’s the powder that I shy away from if forced to load at less than published COLs.
As mentioned before, it’s the seating depth that’s the consideration here. If you could find someone who had 124 XTP JHPs, you could see how that bullet OAL compares to the one you’re loading, and then see if you really are seating them deeper. My 124 XTPs measure .574” +/- .001”.
If I’m forced to load at a COL less than the published data, I’ll subtract a tenth of a grain from the min for every ten thousandths less than the COL. That’s just my rule of thumb for my reloading.

For those still reading, I am not one to take risks, and only want two piles: a pile of 130 PF for IDPA, and a hotter pile for self-defense.

I used to try to use a slower powder for my minor IDPA load, but it was very smoky and very dirty. It happened to be WSF. I switched to Sport Pistol and N320, but something like 231 or 244 works well at minor PF. Hotter loads are safer with a slower powder. I’d recommend you get two different powders. You may also want to investigate chamber reamers, preferably with a gunsmith - it would solve the COL issue.

 

[Walkalong]

You know? It's interesting Hodgdon has them at a 1.120 OAL and an XTP at 1.060, especially considering the XTP is about thirty-thou longer than the RMR Nukes (.573-.577 compared to ~.544-.546 in my batch) with the same diameter. So that equates to about a .030 extra powder chamber difference in my favor with the RMR Nukes. I'm actually safer at the same OAL than the regarded safe XTP distance. Dunno why I didn't look that up before.


It's looking more and more like this is going to be a perfectly safe load to use and that I'm worrying about nothing much at all.

This is what I was going to post, do the math using the OALs and bullet lengths to figure how deep they seat in the case to compare vs simply OAL.

 

[Jim Watson]

This is what I was going to post, do the math using the OALs and bullet lengths to figure how deep they seat in the case to compare vs simply OAL.

Phil Sharpe was tabulating loads by seating depth in the 1930s. He even had some with the same bullet seated two different ways.
But that meant you would have to do the arithmetic to figure out the OAL to adjust your seating die, we can't have that any more.

 

[CurryCornDog]

Phil Sharpe was tabulating loads by seating depth in the 1930s. He even had some with the same bullet seated two different ways.
But that meant you would have to do the arithmetic to figure out the OAL to adjust your seating die, we can't have that any more.

Ha! Lots of replies to sift through, but I'm gonna start with this one. First, thanks for the response. Secondly, I did just that last night, as I am somewhat able to use more than fingers and toes to figure out what I need. Turns out at the lowest seating I used, 1.057", I am a whole .025x"-.029x" safer in every regard while also keeping every bullet off the lands and plunking properly.

I've been reading so damn much that I forgot about an article (probably here) that went over this exact thing. Hell, could've been excerpts from Phil there as well. But it popped back in my head so I got to mathing and looks like I'm g2g.

 

[CurryCornDog]

This is what I was going to post, do the math using the OALs and bullet lengths to figure how deep they seat in the case to compare vs simply OAL.

I appreciate the response. Looks like some of my reading actually paid off! Ha.

I'm going to do a write-up with my Rival and another I have access to with an even tighter chamber and throat and see what comes of it. That'll be down the road when I get me a chrono as well to be a bit more accurate with results, velocities, and at least theoretical pressures from the math thereof. Thanks again for helping compare notes!