RCBS 9mm 124gr

[alfadan]

I have some questions about this combo. There seems to be little data on this bullet in 9mm. Using a lyman 120gr of similar shape out of the lyman 49th book, the min load is 3.3, but that fills the case up right up to base. 4 grains Unique is another load I found, but again that fills the case up, maybe a little compression even. My COAL is 1.165 as limited by my chamber. Are loadings going to be this full? Does anyone have a COAL for this bullet? Thanks

[gpidaho]

alfadan: According to the Lyman Cast Bullet Handbook 4th Edition The Rcbs 9mm 124 CN is seated to a COL of 1.050 in there test loads and I have fired them safely at this length with the powder charges listed. That said I seat my 9mm bullets out to around 1.125 if they plunk test in my pistol barrel and if lubed, the lube groove is in the case. I don't lube my pistol bullets., they're powder coated. Gp

[alfadan]

Thanks gp. I may have to break down and buy that book.

[gwpercle]

The RCBS Cast Bullet Manual number 1 is available on Amazon .
It has data for two 124 grain boolits listed . RCBS #09-124-CN (truncated cone - plain base) and RCBS # 9mm-124-RN (round nose - gas check) . Not a bad manual to own if you have RCBS moulds .
For the round nose design 9mm-124-RN , the data for Unique is :

Minimum : 5.1 grains Unique @ 1102 fps

Maximum : 5.5 grs. Unique @ 1122 fps

No seating depth ( OAL ) is listed

I use 4.7 to 5.0 grains of Unique w/ a 125 grain TC-GC design made by NOE ... very similar design to 09-124-CN.
I didn't think there was room in the 9mm case for that much Unique but it fools you ...there is !

The powder charges for the plain based 124 gr. TC bullet are:
min. - 4.7 grs. Unique @ 1083
Max. - 5.2 grs. Unique @ 1167
Gary

[alfadan]

Thanks for that. I will get that book too as Im very fond of RCBS molds.

[gwpercle]

Thanks for that. I will get that book too as Im very fond of RCBS molds.

Surprisingly ... I use this book a lot ... for data and as a cross reference . It's out of print but worth having . I wish a company would do a reprint of it .
Gary

[alfadan]

I'll probably get it off ebay, since I stopped buying from amazon.

[alfadan]

looks like Ive got a problem with the expander in my Lee dies is too short, causing swaging. Been reading some threads about it here and will update. I had no feeding issues though and 3gr 700x was nice and mild and probably try 3.3 or so next.

[fcvan]

I use the Lee 356-125 2R, the first mold I bought for myself, for the first I bought. It drops as cast at .358 and I shoot them as cast or sized to .358 when PCd.. Loaded over 5 gr Unique has been my go-to load for 9mm. When I bought a .357, I loaded 5 gr Unique under the same boolit in 38 Spl. loads. When I started shooting 40 S&W I cast the Lee 401-175 TC (mine weighs 180 gr) over 5 grains of Unique. See a pattern? It just works, providing the volume of gas to propel without attaining dangerous pressures. Each load has more room at the top, I just like the 5 gr charge.

[P Flados]

When I go to Alliant's web based reloading data, I frequently get frustrated by the lack of powder choices listed. Unique is probably a good powder for near max velocities in the 9mm, but they have no current data for it.

I still have a pdf of a 2000 Alliant load data pamphlet that has data for most all of their powders, but it does not list actual brand of bullets used so I worry that using the AOL listed will get a different bullet seating depth (and different load density) if I use a different bullet.

As a Quickload user, I have found that you really need to try to keep the load density the same as the published load when you substitute a bullet of the same weight but a different length.

As best I can tell, the 2000 Alliant load data had 9mm loads for Unique right at 100% load density (full but not compressed).

Now for 700x, a reference Hodgdon load is a Sierra 125 FMJ at 1.090 over 3.6 gr of 700x. This bullet is 0.581" long so with a 0.754 case, the seating depth would be 0.245". You can measure your bullet length and adjust as needed to get the same seating depth.

Of the two powders, I would go with the 700x for general purpose shooting loads where you do not really need max velocity. I would also go with a charge that is a little higher than the minimum charge that reliably cycles the action on your gun. Your proposed 3.3 gr sounds pretty good as long as you are not seating the bullet deeper than 0.245" into the case.

[Bashby]

looks like Ive got a problem with the expander in my Lee dies is too short, causing swaging. Been reading some threads about it here and will update. I had no feeding issues though and 3gr 700x was nice and mild and probably try 3.3 or so next.

Lyman m die solved my swaging problem in 9mm.

[mdi]

I just checked Amazon and the RCDS manual is $76.00, used from $45.00 and up (a bit pricy for me, and I no longer buy used books unless I see them first.). I have been casting for quite a while and for me, a cast 124 gr bullet is a 124 gr boolit. Just about any data is interchangeable and OAL is easily determined. As with any new caliber or component, start low and work up...

[alfadan]

Many thanks for the info gentlemen. I'm turning a longer reach expander for my lee die now and will keep working on these loads. Its been fun trying out a new-to-me cartridge again.

[Pirate69]

Not trying to light a flame thrower here but the velocities for the 5.1grs and 5.5 grs loads look strange. An 8% increase in powder charge only gives a 20 fps increase in velocity. Thought I would run a quick check with QuickLoad. First of all, could not find RCBS cast boolit data for 9mm 124-RN. So I thought I would use Lyman 121 grs 356242 data as an approximation. Assuming a 4" barrel. This are the results:

5.1 grs Unique
100.4% load density
29,025 psi
1,145 fps

5.5 grs Unique
108.4% load density
34,805 psi
1,220 fps

Think there may be a typo in the manual?



The RCBS Cast Bullet Manual number 1 is available on Amazon .
It has data for two 124 grain boolits listed . RCBS #09-124-CN (truncated cone - plain base) and RCBS # 9mm-124-RN (round nose - gas check) . Not a bad manual to own if you have RCBS moulds .
For the round nose design 9mm-124-RN , the data for Unique is :

Minimum : 5.1 grains Unique @ 1102 fps

Maximum : 5.5 grs. Unique @ 1122 fps

No seating depth ( OAL ) is listed

I use 4.7 to 5.0 grains of Unique w/ a 125 grain TC-GC design made by NOE ... very similar design to 09-124-CN.
I didn't think there was room in the 9mm case for that much Unique but it fools you ...there is !

The powder charges for the plain based 124 gr. TC bullet are:
min. - 4.7 grs. Unique @ 1083
Max. - 5.2 grs. Unique @ 1167
Gary

[fredj338]

Too many worry about OAL & compression. Many powders can be compressed, Unique is one in 9mm that works just fine compressed. OAL is also so misunderstood. Any book data really means little. The OAL has to fit your bullet in your gun. So I load as long as allowed to fit my chamber & magazine. Adjust powder as required. I have shot a lot of Unique under 124gr LTC. 5gr is pretty universal for me with any 124gr lead bullet. OAL varies with bullet shape. The only vel numbers you can trust are those from your gun over a chrono. Nothing else posted matters much.

[P Flados]

...
Think there may be a typo in the manual?

Probably not. Manuals usually show test results. Test results are what they are. Some variance in getting "expected results" can happen even if they were run on the same day with the same components and equipment.

Secondly, I have read that compression can slow down ignition. As such I never expect compressed loads to behave in a linear fashion as charges are increased.

[winelover]

Fred, nails it. Reloading data is just a guide. Nothing set in stone. Forget COAL and measure O-give length, for your barrel, and record it. Use it for making dummy rounds. Cycle those manually, though the action, checking that the length doesn't change, afterwards. I've been loading 9 mm for over forty years. I started with the RCBS 125 RN GC bullet. Five grains of Unique was my most used load. I purchase Unique by the 8 pound jug, because it's so versatile. Wouldn't be without it.

Winelover

[Sailormilan2]

Using the very old Lyman 45th Reloading Manual, the Unique powder listings for the Lyman 356402 bullet, which is similar to the RCBS are as follows:

Starting 4.4 gr/999 fps, and a max of 6.0 gr/1243 fps.

That old Lyman manual tends to be fearless at times. The newer 49th Edition doesn't show Unique.

[canyon-ghost]

Word of warning, Speer 13 says the 9mm can develop major pressure if the bullet is seated too deeply. I wouldn't compress the load. Have been using 3.2 grains of Bullseye out to 100 meters. I get good accuracy from the old starting load. I fired some with more powder but, backed down to save my pistols. 9mm doesn't need any recoil in lead that approximates jacketed. Until you fire them you may not know how mean they are.

[Sam Sackett]

looks like Ive got a problem with the expander in my Lee dies is too short, causing swaging. Been reading some threads about it here and will update. I had no feeding issues though and 3gr 700x was nice and mild and probably try 3.3 or so next.

Alfadan, If you are having problems with the case sizing your bullet down using Lee dies, get the expander for a 38 S&W from Lee. Swap it out in the 9mm Lee Powder through die. The 38 S&W will expand the case about 2 thou more. This made a lot of difference for me.

Sam Sackett

[alfadan]

Just an update, I made a powder-through-expander plug and have solved about 90% of my problems. loaded to 1.15" with 3.5gr 700x. Too muddy to set up the chrony, but they shot very well, clean cases, just a little leading with my crummy aloy, and just felt right compared to some factory 9mm I've shot.

[mfraser264]

Have shot a few thousand of this bullet design by RCBS. Using 4.0 of Bullseye, cast of Linotype, gas checked, sized to .356 and seated to 1.130" with a taper crimp only, these work very very well. Very accurate and have feed flawlessly through a Browning Hi Power and Ruger SR9. Glad that another mold was obtained recently to improve casting output. Need to cast a large quantity as the stock of jacketed 9mm is dwindling and this will become the mainstay for me even when jacketed become available.

[Bashby]

The 38 S&W expander didn’t work out for me, it has too much taper to it and I was still swaging bullets. I modified an NOE expander which worked ok. Now I have an M-die and it works well. I’ll need to look for a powder through option if I ever move up from single stage.

[alfadan]

Great day here today so broke out the Chrony. 3.5 grains 700x with temps in mid 50s, 970 fps. Might bump it up to 3.8 or so, but these shot clean and reliably.

[243winxb]

Speer load data

[alfadan]

Thanks for the data. I don't know, I may try unique again, just wouldnt think my 700x load to be that hot at 970 fps, but if I can better performance with less bang, why not?

[P Flados]

alfadan,

Quickload (QL) does not have 700x. I fudged a Lee 124 TC load with 3.6 gr Red Dot (a very similar powder) to give the same performance (1007 fps from a 4" barrel at 31 ksi) as shown in the Hodgdon data for a 3.6 gr 700x load under a Sierra 125 FMJ. To make it match I adjusted the AOL to 1.116". I then found I had to shorten the barrel to 3" to get down to 980 fps. If you are shooting a gun over 3" your pressure is less than the Hodgdon 31 ksi.

I did not see your barrel length and did not seen any reference to whether it was +p rated.

Ignoring the barrel length issue, to go from 31 ksi to the rating for 9mm (35 ksi), QL predicts it will take 3.81 grs and a 3" gun velocity would go up to 1018 fps.

If your gun is +P (38.5 ksi), QL says you would hit the limit right at 3.99 grs and velocity for a 3" gun would go to 1050 fps.

QL said my fudged load went to 100% fill at 3.61 gr. As such you are likely to be heading toward compressed powder if you continue working upward with the charges.

I have found some headstamps of range pickup brass to be heavier than typical. This translates to less internal space. If you are going to push things, I would run some of you brass over the scales and use only the lighter brass (your call as to where to make the cut). I personally use range pick up brass, but only reload FC, Blazer and CCI headstamps. It seemed to help me with more consistent results.

[alfadan]

Thanks P, it is a 3" kimber micro9, so those numbers seem to add up. I think the slower Unique will probably be the way to go if I want to bump velocities up without pressure getting crazy. Id like to get it up about 1050 or 1100 to better approximate the feel of commercial SD I would carry, if there were any to buy that is.

[P Flados]

I plugged in 5.2 Unique with no other changes to get 1107 fps at 35 ksi.

Note that case fill is an ugly looking 111.2% with this load.

Since the Micro 9 does appear to be +P, I would try working up to around 3.8 or so with the 700x before going to the Unique.

With the short barrel, the muzzle blast with Unique is going to be a lot worse than with 700x. Although is it nice to practice close to real SD, I am betting that a little warmer with the 700x will start getting snappy enough for your training needs.