RMR 9mm 124gr JHP in-house bullet - evaluation

[vaalpens]

I have just received my first order of the "New RMR 9mm 124 grain Jacketed Hollow Point (made in-house by RMR)" bullets.

My plan is to test these bullets in 357sig, and maybe later in 9mm. This thread will be used to document the process I will put these bullets through:

• Taking some measurements
• Making sure they will work in 357sig
• Working up some loads using some of my known loads so that I can compare them with other bullets
• Test the loads and documenting velocity and accuracy
• Since they are supposed to be expanding JHP's, my selected load will be tested for expansion using 1gal water jugs

I have not started any measurement or validation yet, but following are a couple of pictures showcasing the new bullets:

 

[Walkalong]

I'm interested in how the in house 124 JHPs do. I really liked the ones he had previously. Should have bought more than I did.

 

[Walkalong]

Making sure they will work in 357sig

Sure look look they should.

 

[JimKirk]

Those look good! I do want a copy of that card drawing

 

[Ghost In The Fog]

and maybe later in 9mm. This thread will be used to document the process I will put these bullets through:.[/QUOTE]


I bought 500 of the old ones in December and I am on the same sort of journey with 9MM.
I will be anxiously awaiting your test results. My preliminary test in one gallon jugs are FANTASTIC. They expand as good as and more consistently the my SD Winchester Kennitics. I am very happy with them and I am waiting for RMR to get the polish thing finalized and I am definitely buying more.
As soon as I get a chance later today, I have 100 more loaded and ready to chrono and test using Ramshot Silhouette
The video is a slow motion of the RMR 124 JHP. I have another of 1 gallon jugs.

Video 20170127123500698 RMR 124JHP[1] on Vimeo

• Ghost In The Fog
• Mar 3, 2017

This is "Video 20170127123500698 RMR 124JHP[1]"

 

[vaalpens]

I took some measurements of 10 random bullets. Please note that I have just used a cheap Frankfort Arsenal scale to weight the bullets and a Mitutoyo Absolute Digimatic digital caliper to measure length and diameter:

The bullet weight range was from 123.5gr to 124.1gr, with 5 coming in at 123.5gr. Bullet weight is not a big issue for me when it comes to 357sig:

5@ 123.5gr
1@ 123.8gr
1@ 123.9gr
2@ 124.0gr
1@ 124.1gr​

The bullet diameter is much more important for 357sig due possible setback. The diameters I saw were:

3@ .3545"
2@ .3550"
4@ .3555"
1@ .3560"​

Bullet length is also not that important, where bullet shape is much more important in 357sig. The shape will be validated in a later test. The bullet lengths I saw were:

2@ .5490"
2@ .5505"
3@ .5510"
1@ .5520"
1@ .5525"
1@ .5530"​

 

[vaalpens]

I'm interested in how the in house 124 JHPs do. I really liked the ones he had previously. Should have bought more than I did.

I liked the previous JHP's in 9mm, but had to load them to a COL of 1.150" in 357sig. They worked well but I prefer a lower COL on my 357sig.

 

[vaalpens]

Sure look look they should.

When I first saw a picture of the bullets and saw the stubby nose, it surely looked like something that will work well in 357sig. But it is a combination of shape and diameter that makes it work.

 

[vaalpens]

Those look good! I do want a copy of that card drawing

I think this is the batch before they could clean them properly. Shape looks good.

PM on the way with image.

 

[vaalpens]

and maybe later in 9mm. This thread will be used to document the process I will put these bullets through:.


I bought 500 of the old ones in December and I am on the same sort of journey with 9MM.
I will be anxiously awaiting your test results. My preliminary test in one gallon jugs are FANTASTIC. They expand as good as and more consistently the my SD Winchester Kennitics. I am very happy with them and I am waiting for RMR to get the polish thing finalized and I am definitely buying more.
As soon as I get a chance later today, I have 100 more loaded and ready to chrono and test using Ramshot Silhouette

Thanks for the comments and sharing the video. I also liked shooting the old JHP's, especially into water jugs. They do expand very well, but at 357sig speed not much was left of the original bullet when testing them in water jugs. I would not use the old one for SD in 357sig, but they are great for non paper type target shooting.

 

[vaalpens]

The next measurement/calculation I did was to figure out what my starting COL could be. When I do my plunk and cycle test then it is possible that I will adjust the COL, but this calculation basically gives me a starting point that will work for the bullet shape and length.

There is a picture below of how I measure it, but basically I take the possible COL, bullet length, length of the sized case and length of the bullet placed nose down in the case, then calculate the possible gap between the mouth of the case and the start of the bullet ogive, and also the seating depth of the bullet for the COL I have picked.

This bullet measured the same length as the Nosler 124gr JHP, but with a shorter nose. Comparing these two bullets made me decide to target a possible COL of 1.125", or maybe even a 1.120" if the plunk and cycle test brings up any issues.

The calculated seating depth will determine where I start with my load development. The seating depth is .014" deeper than my MG load, .020" deeper than my V-Crown loads, but .002" shallower than my old RMR JHP loads. If I go with a COL of 1.135", then these numbers will obviously change.

These are my measured and calculated numbers:
Bullet Length: .5510"
Case length: .8640"
Case+Bullet length with bullet upside down in case: 1.218"
COL: 1.125"
Bullet seat: .2900"
Gap between case mouth and start ogive: .0640"

These calculation are just guidelines for me to determine what a good starting point will be for the COL and loads.

And this is how I measure the Case+Bullet length with bullet upside down in case:

 

[Walkalong]

3@ .3545"
2@ .3550"
4@ .3555"
1@ .3560"

For this you should use a micrometer to get the in betweens.

I would like to see them all between .355 and .356 (Or even a hair more), before seeing any below .355. The micrometer would tell us if those @ .3545 were under that or over that. Do they have a pressure bump or is the diameter the same all the way down?

 

[vaalpens]

For this you should use a micrometer to get the in betweens.

I would like to see them all between .355 and .356 (Or even a hair more), before seeing any below .355. The micrometer would tell us if those @ .3545 were under that or over that. Do they have a pressure bump or is the diameter the same all the way down?

Walkalong, fr 357sig I prefer .3555" which means it is on over side of .3550". The .3545" concerns me a bit, but it could just be the way I measure it. Nothing is perfect, and that includes me. The diameter seems the same all the way down, which is what I am looking for.

My next validation step will be the setback test, so I will definitely include at least one of the .3545" diameter bullets.

 

[vaalpens]

I have now completed the last tests to make sure I can safely load these RMR 124gr JHP's in 357sig:

Two dummy rounds were created. One with a .3545" diameter and another with a .3555" diameter. Both these bullets were loaded to a COL of 1.1255". I was targeting 1.125", but 1.1255" was close enough. This is a picture of the two dummy rounds:


Both these bullets were passed the plunk test using my P229 357sig barrel.

The bullets were also tested to make sure the case mouth was below the start of the ogive. This value was calculated before I create the dummy rounds, but I still did the test just to make sure. This is a picture of the test:


The next test was the cycle/setback test. Each bullet was loaded one at a time, slide was locked back, and the slide was released. The bullet was then ejected and the COL measured. Following are the results:

.3545" diameter:
COL after cycle #1: 1.1255"
COL after cycle #2: 1.1255"
COL after cycle #3: 1.1255"
COL after cycle #4: 1.1250"

This bullet passed my cycle/setback test.

.3555" diameter:
COL after cycle #1: 1.1260"
COL after cycle #2: 1.1260"
COL after cycle #3: 1.1260"
COL after cycle #4: 1.1250"

I have seen the slight increase in COL before, but it could just be how good the caliper measurement is. This bullet also passed the cycle/setback test.

The next test was to use the same bullets that just went through the cycle/setback test and perform a bathroom scale/setback test. For this test I use a digital scale, which mean I need to hold the bullet at the same pressure for about 5 seconds before the weight will register. For me this shows a lot.

The first bullet was held at the constant pressure for 5 seconds and registered 23lbs. After the test the COL was measured again and I measured a 1.1245". This bullet passed the bathroom scale/setback test.

The second bullet was held at the constant pressure for 5 seconds and registered 29lbs. After the test the COL was measured again and I measured a 1.1250". This bullet passed the bathroom scale/setback test.

Both these bullets passed all the tests and I now feel comfortable loading the new RMR 124gr JHP bullets in 357sig with my load process.

 

[longdayjake]

For this you should use a micrometer to get the in betweens.

I would like to see them all between .355 and .356 (Or even a hair more), before seeing any below .355. The micrometer would tell us if those @ .3545 were under that or over that. Do they have a pressure bump or is the diameter the same all the way down?

We make this bullet a little different than others do. There is some variance in the diameter from the top of the body to the bottom. Typically, starting about halfway up the body is where our final nose finish station hits. Typically the upper half of the bullet comes out to .3555 and the base of the bullet was coming out at .3554. We were using digital Mitutoyo micrometers to test the diameters. I'm kind of curious why the .3545 was there. Do you know where on the bullet you measured it from?

 

[longdayjake]

Also, be aware that testing for expansion in water will likely strip the jacket off of the core. I'm not sure why, but without some sort of bonding, water tends to be hard on jackets. We tested them in FBI calibrated ballistics gel to get consistent expansion.

 

[vaalpens]

We make this bullet a little different than others do. There is some variance in the diameter from the top of the body to the bottom. Typically, starting about halfway up the body is where our final nose finish station hits. Typically the upper half of the bullet comes out to .3555 and the base of the bullet was coming out at .3554. We were using digital Mitutoyo micrometers to test the diameters. I'm kind of curious why the .3545 was there. Do you know where on the bullet you measured it from?

Jake, thank for taking the time to respond to my thread. I went back and measured a few more bullets, and what I found was that a measurement towards the base of the bullet is where I see the.3545", if I see them. I don't have a micrometer and I know the way I measure is probably not as accurate as it should be. The method I used was to just put the jaws on the bullet, and use that reading. Normally the measurement will change if you change your grip or do something.

It seems that I should probably change the way I measure bullets, and maybe use the thicker part of the jaw to get a more consistent measurement. I have included two pictures of the same bullet. The first shows the method where I just applied the jaw and took the measurement, and the second one is where I used the thicker part of the jaw, which makes more sense when it comes to how the bullet will fit in the case neck.




For me there are more than just measurements when it comes to loading bullets in 357sig:

• How easy it is to find a working COL and how wide the range is. These bullets are excellent in that respect since I can increase or decrease the COL without worrying about the case mouth intruding on the bullet ogive.
• What is the tension feel when I seat the bullet using a single stage. These bullets again were very good and I had a solid tension feel, even for the .3545" diameter bullet.
• When I do my cycle/setback test, what sort of deviation do I see. These bullets were excellent again. Both bullets showed no deviation in the COL until the end, but that could be due to the bullet being pushed down on the nose using around 25lbs

Thanks again for giving the 357sig reloader community another good bullet option. Now if RMR can just start producing the 124gr FP FMJ as promised.

 

[vaalpens]

Also, be aware that testing for expansion in water will likely strip the jacket off of the core. I'm not sure why, but without some sort of bonding, water tends to be hard on jackets. We tested them in FBI calibrated ballistics gel to get consistent expansion.

Jake, yes I understand that water is harder on these bullets, but is is the only medium I have. It still gives me an apples to apples comparison with other bullets. I know I will never see those beautiful expanded bullet results, even with premium bullets, but they do give some indication on if it is just a jacket separation (due to water) or does it actually break up.

Thanks again for taking the time to comment on this thread.

 

[longdayjake]

Those are some legit calipers. These were from our first run on the machine so I'm sure we have a little to learn and our consistency will increase as we go. I really appreciate seeing pictures and your feedback on them as it will help us to know what we can do to make them even better. When I approved this bullet the bases were all coming out at .355 minimum and .3556 maximum. I specifically told them I wouldn't accept the machine if it came under .355.

And thanks for trying them out in .357 sig. Believe it or not, I specifically had you in mind when I requested/approved this ogive design from our engineer.

 

[vaalpens]

Those are some legit calipers. These were from our first run on the machine so I'm sure we have a little to learn and our consistency will increase as we go. I really appreciate seeing pictures and your feedback on them as it will help us to know what we can do to make them even better. When I approved this bullet the bases were all coming out at .355 minimum and .3556 maximum. I specifically told them I wouldn't accept the machine if it came under .355.

And thanks for trying them out in .357 sig. Believe it or not, I specifically had you in mind when I requested/approved this ogive design from our engineer.

Jake, these bullets will be great, and just from loading the dummy rounds, I could feel that they were very uniform and I really liked how easy it was to use the COL I was planning on using. Your older JHP's was a tight fit in 357sig and had to load them to 1.150". A narrow range and not much to play with.

Based on your comments on where you would expect the .3545" diameter, I decided to measure 10 bullets again and at least take my hands/fingers out as variables. I basically placed the calipers on a table and then measured the bullet in the front part of the jaw, and then again just behind it where the thick part of the jaw start. The front measures about .115" from the bottom, and the thick part up to about .22" from the bottom. These measurements came out very consistent:
Front part of jaw: 4@ .3550" and 6@ .3545"
Thick part of jaw: 10@ .3555" (excellent!)

Here are some pictures to show how I measured them with hands/fingers removed as a variable:



Thanks for the kind word regarding having my previous comments in mind when deciding on the ogive design. It really means a lot that our comments at least carry some weight.

 

[vaalpens]

Based on the seating depth of these RMR bullets, I have decided on my first loads. I will be using BE-86 starting from 7.5gr and ending at 7.8gr. This is a little lower than where I wanted to start, but since the bullet will be seated a little bit deeper than some of my previous load, I decided to start at 7.5gr. Following is a picture of the completed load I will be testing. Normally I would load/test 5 rounds per load, but this time I have done 6 rounds, 5 rounds for chrono/grouping and 1 round for expansion in 1gal water jugs.:

 

[vaalpens]

I loaded these bullets up on Saturday and tested them on Sunday. It was a nice overcast afternoon which normally creates excellent conditions for the chrono.

Following are the test results for the RMR 9mm 124gr JHP bullets in 357sig. Test was performed with a SIG P229 @ 15yards from a rest:

357sig, SIG P229, 3.9"
COL: 1.135"
RMR, 124gr, JHP, BE86, 7.5gr, SBPRSP
Average: 1257
ES: 16
SD: 7.2
Force: 435
PF: 155
Velocities: 1251, 1267, 1251, 1262, 1254
Grouping @15yards: 2.17"

357sig, SIG P229, 3.9"
COL: 1.135"
RMR, 124gr, JHP, BE86, 7.6gr, SBPRSP
Average: 1271
ES: 16
SD: 6.1
Force: 445
PF: 157
Velocities: 1278, 1274, 1269, 1274, 1262
Grouping @15yards: .95"
**Please note that the two top bullet holes are from the previous load with a not so good grouping.


357sig, SIG P229, 3.9"
COL: 1.135"
RMR, 124gr, JHP, BE86, 7.7gr, SBPRSP
Average: 1285
ES: 19
SD: 6.9
Force: 455
PF: 159
Velocities: 1288, 1284, 1275, 1284, 1294
Grouping @15yards: 1.31"

357sig, SIG P229, 3.9"
COL: 1.135"
RMR, 124gr, JHP, BE86, 7.8gr, SBPRSP
Average: 1306
ES: 23
SD: 8.8
Force: 470
PF: 161
Velocities: 1303, 1297, 1320, 1309, 1302
Grouping @15yards: 1.59"

My previous experience with BE-86 and JHP type bullets definitely helped me to dial this bullet/powder combination in to get a very good grouping.

It seems that these bullets are very accurate, and also created very consistent loads. The SD numbers were 7.2, 6.1, 6.9 and 8.8. All very good numbers.

I also tested the 7.6gr load in 1gal water jugs. At 357sig speed the first jug exploded but did not leave much of the bullet intact. I will post a picture later to show what I recovered from the bullet, but it seems at 357sig speed, water is probably not a very good medium to test these bullets for expansion.

 

[murf]

great results, vaalpens. can you put some denim in front of the jug and see if the hollow point plugs up?

murf

 

[vaalpens]

great results, vaalpens. can you put some denim in front of the jug and see if the hollow point plugs up?

murf

murf, thanks for the comments. I'm not sure if denim will change anything, but I will definitely include it in my test next time. I am also planning on loading these bullets in 9mm and see how they perform. I expect better weight retention at the lower 9mm velocity.

 

[vaalpens]

I also tested the 7.6gr load in 1gal water jugs. At 357sig speed the first jug exploded but did not leave much of the bullet intact. I will post a picture later to show what I recovered from the bullet, but it seems at 357sig speed, water is probably not a very good medium to test these bullets for expansion.

Following are a few pictures from what was left of the bullets after being shot into 1gal water jugs at about 1271fps. These pieces were extracted from the 4th jug, but I could not find any additional pieces.