Looking for 9mm recipe for .355 dia 115 gr bi-metal RN concave base

Fairly new to reloading and purchased a quantity of bi-metal RN with concave base bullets. I have manuals from Lyman, Hornady and Speer as well as reloading info from Allianz, but can’t find any recipe specific to the concave base design. The bullets measure .602 - .604” in length, and tend to run a few (3-5) grains light in weight.

Other comparable FMJ projectiles I have measure .550 to .560” length.

Have tested using
W231 4.1 gr, 4.2 gr, 4.3 gr, 4.4 gr and 4.5 gr
WSP, FED 100, CCI 500 primers
COL 1.148, 1.140, 1.137

At present I only have CCI 500 primers available.

All variations passed plunk test, cycled and fired successfully in Springfield hellcat. XDM compact, XDM OSP and KelTec Sub2000. The lower charges ejected ok, but for the most part at my feet. The longer 1.148 COL resulted in many cases with heavy soot.

Was most pleased with the accuracy with the W231 4.4 gr, WSP, 1.137 COL loads which was my latest test.

Any suggestions will be much appreciated..

 

I too am fairly new, but I also have the Hellcat and a couple H&K 9mm's. Anyway, I've used the Hornady (#35557) 115gr RN FMJ with great success, however my H&K's seem to need a hotter load (at the upper end of the spectrum), than my Hellcat due to ejection inconsistencies. While these bullets do not have a concave base, I don't think that has much to do with it. 115 gr is 115 gr. I may be ignorant here...someone can chime in.

I am using Titegroup 4.1 grain and 1.107 OAL or thereabouts. HTH...

 

Thanks ManFromMontana. I recently picked up some of those Hornady RN FMJs. Haven’t been able to put my hands on any Tiegroup locally but will keep trying.

 

BTW - I am originally from Dallas...now in Montana. "Don't Mess with Texas" !!

 

Bi-metal? First time I've heard that term describing a pistol bullet. Are the bullets copper plated lead? Where are you getting your data? The powder charges sound OK, but your OALs seem to be a bit long for a 115 RN/FMJ. But I don't know exactly what bullet or data you're using. Normally soot indicates lower pressure not sealing the case/chamber and gas/soot leaking and depositing on the case. Not dangerous, and normally doesn't hurt the gun. Sometimes case capacity from deep/shallow seating and concave/hollow based bullets can affect pressures in a high pressure round (9mm), and long seated, concave based bullets may be lower pressure, sooting the cases.

The handloads are functioning, sound accurate, but I'd recheck the data for OAL...

 

Welcome to THR.

9mm FMJ/RN profile bullets have shorter bullet base and can suffer from neck tension issue (especially when using longer 1.150-1.160" OAL) and some manufacturers use varying levels of concave base to lengthen the bullet base to improve neck tension (Us reloaders and match ammunition manufacturer like Atlanta Arms use shorter OAL like 1.130"-1.135" down to 1.100" to improve neck tension) - https://www.thehighroad.org/index.p...hollow-base-bullets-now.872493/#post-11587269

Looking at the comparison picture of various 115 gr FMJ, you should notice concave base bullets on the right are longer.

Heavy soot on case could indicate poor powder burn efficiency from insufficient chamber pressure build which can be improved by increasing powder charge and/or using shorter OAL that increases neck tension.

But you are also using pistol caliber carbine (PCC) and blowback action tends to leak a lot of gas as bolt/buffer moves back from chamber (compared to locked breech action of pistols) and using higher powder charge/shorter OAL will improve chamber pressure build.


As to load data for concave FMJ bullets, I reference load data for regular FMJ/RN profile bullets with flat base.

Here are Hodgdon load data for Lead RN and FMJ bullets (Since we can reference load data for slightly heavier bullet) - http://www.hodgdonreloading.com/data/pistol

• 9mm 115 gr Lead RN W231/HP-38 COL 1.100" Start 4.3 gr (1,079 fps) - Max 4.8 gr (1,135 fps)
• 9mm 125 gr Sierra FMJ W231/HP-38 COL 1.090" Start 4.4 gr (1,009 fps) - Max 4.8 gr (1,088 fps)

And here is Speer load data for RN profile bullets (Total Metal Jacket is thick plated bullet that can be driven to jacketed load data) - https://www.speer.com/reloading/handgun-data.html

• 9mm 115 gr Speer TMJ RN W231 OAL 1.135" Start 4.4 gr (1026 fps) - Max 4.9 gr (1133 fps)

Starting at 4.1 gr and longer 1.148" OAL, you were below published start charges and accuracy likely improved due to higher chamber pressures contributing to more efficient powder burn and pressure build.

With various 115 gr jacketed and plated RN profile bullets loaded to 1.130"-1.135" OAL, 4.5 gr of W231/HP-38 tend to start reliably cycling the slides of my pistols (Especially compact/subcompact with stiffer recoil springs) and 4.6-4.7 gr will trend greater accuracy. My 9mm reference load uses 4.8 gr W231/HP-38 loaded to 1.130"-1.135" OAL.

So try shorter OAL at 1.130"-1.135" (Typical OAL variance many member get from progressive presses) and test 4.5, 4.6, 4.7 and 4.8 gr and see which powder charge produces smallest groups. And exercise care to not tilt the bullet - https://www.thehighroad.org/index.php?threads/beginner-reloading-problems.877215/#post-11687625

And likely, powder charge that produces smallest groups for pistols will also produce better accuracy for your carbine.

And if you want to reload more consistent rounds by reducing reloading variables, check out this step-by-step guide - https://www.thehighroad.org/index.p...-and-discussions.778197/page-10#post-11419509

 

Bi-metal FMJ is likely Tulammo (Russian) FMJ with jacketing that attracts magnet - https://www.midwayusa.com/product/3083365861

While I prefer copper jacketed bullets, even brass jacketed bullets (Montana Gold, Remington, Armscor), I guess during component shortage, you gotta use whatever you can get, right?

Likely the steel used for bullet jacketing (gilding metal) will be softer than barrel metal ... But if you are using surface hardened Glock/M&P Tennifer/Melonite barrels, shouldn't be an issue. Not sure about non-surface hardened barrels.

 

What specific brand of bullets are you using?

 

That weight variance I expect for heavier 45ACP lead bullets, not 9mm jacketed bullets.

Most jacketed 9mm 115 gr FMJ bullets will vary around 1.0 gr with match grade bullets varying less than 1.0 gr.

I would suggest you consider trying RMR 115 gr FMJ that varies by less than .5 gr and used by ELEY for their centerfire match ammunition. Guns America Digest tested RMR jacketed bullets and found .3 gr weight variance - https://www.thehighroad.org/index.p...ine-of-match-ammunition.854750/#post-11201936

Although RMR is out of stock on 115 gr FMJ, since they manufacture their own bullets, back order and you will receive your bullets when they are made - https://www.rmrbullets.com/shop/bul...rmr-full-metal-jacket-round-nose-bullets-new/

And RMR offers 5% THR discount - https://www.thehighroad.org/index.php?threads/rmr-discount-code.865251/page-8#post-11672833

 

Without having a sample for the Watson Test Kitchen, I can't provide a "recipe."
But my loads with 115 gr gilding metal jacketed are about like your heaviest powder charge and your shortest OAL.
I adjust loads to chronograph either at factory velocity for defense gun practice or minor power factor for competition.
Thing is, there is not much difference with 115 gr bullets.

 

As I understand it’s a very thin copper plate.

Montana is awesomely beautiful! The warmer Texas climate is more compatible with my old age.

 

Wish I knew the brand! They are factory seconds from Midway. I started with data from Hornady 115 gr FMJ RN but was initially concerned their 1.100 COL might result in excess pressure if the longer projectile was seated to the same length as the FMJ. THANKS FOR YOUR INSIGHT.

 

Thank you! I actually have both 125 and 124 gr on order (since August) from RMR. They just advised me it will be a couple more weeks before shipment.

 

indeed at time of shortage you use what you can get..these bullets are factory seconds from Midway. I contacted them but they declined to disclose manufacturer. They do in fact attract magnet and my research seemed to establish that are steel coated with a super thin layer of copper.

 

LiveLife, your post is awesome and so helpful for a newer reloader like me and I will study your references in more detail. I don’t have a chronograph but your reply gives me confidence to work my way up higher loads. Thank you!

 

Thank you!

 

I didn’t see where the OP had the bullet weight? I would advise you establish max and working COL for the various guns and decide what COL then. IF the OP was 115 gr RN then 1.137” is right in line with what I shoot for with 115. Keep in mind, shortening COL for a given charge will increase pressure, so always work up your loads safely. 231 is forgiving in this regard, Titegroup, OTOH, is not. I do use a lot of Titegroup, just be extra careful with it, especially new reloaders.
First time I’ve heard of BiMetal bullets and if they do have a steel jacket what bullet types do you use for a comparison load data?

 

Thanks for the help and encouragement. Y’all are so danged helpful here and I’m totally open to learning from you who have “been there, done that.”

the bi-metals have a steel jacket with Avery thin copper coating. Easy to pick up with a magnet if you spill the box. The only other 9mm 115 he I’ve used so far are Montana Gold RN. Just picked up some Hornady RN but haven’t tried yet.

 

I know it’s been some time since my original post, but I finally was able to get to the range and test rounds using your suggestions.

Here is an update:

Test 1:

9mm 115gr RN CB projectiles
Blazer Cases
W231 charge 4.4, 4.5, 4.6, 4.7, 4.8 grains
CCI 550 primer. (Yes magnum primer, as that was all I had!)
COL/OAL 1.135

Fired 5 rounds each in Springfield XDm OSP, XDm, and Hellcat

The shorter COL/OAL remedied the excess sooting issue on the fired cases. Extraction was still noticeably weak for the 4.4 and 4.5 charge weights.
Noticed smoother action beginning with charge of 4.6 grains and improved grouping as well. Ejection with 4.7 and 4.8 grains was more comparable to that of factory rounds. Recoil, smooth action and ejection felt best at 4.8 grains and produced the best groupings (admittedly at close range) with the XDm OSP and XDm. I did not shoot 4.8 grain charge in the Hellcat, but was quite satisfied with the results of the 4.7 grain charge in that firearm. None of the firings revealed indications of excess pressure.

Test 2:

9mm 115gr RN CB projectiles
W231 charge 4.4, 4.5, 4.6, grains
CCI 550 primer. (Yes magnum primer, as that was all I had!)
WIN Cases
COL/OAL 1.130

Fired 5 rounds each in Springfield XDm OSP, XDm, and Hellcat

The 4.4 and 4.5 grain charges again resulted in weak ejection, although groupings were quite consistent and satisfactory to me considering my relatively low skill level. Recoil remained low even with the 4.6 grain charge and the case ejection was much improved. Again, no signs of excessive pressure were observed.

one other observation is that sometimes observed a smokier gas discharge from the barrel and wonder if that is just a characteristic of the powder. I wouldn’t characterize it as excessive, but definitely noticeable as compared to when firing factory rounds.

To follow up I plan to produce this recipe with charges of 4.7 and 4.8 grains.

Of note, I cannot distinguish any difference when using magnum vs standard primers. Since I have been able to secure a small supply of standard primers I will be using them as long as supplies remain available.

Feeling much more comfortable with my loading processes now and look forward to working up loads with other projectiles and powders.

I welcome any comments and suggestions. Thanks.

 

Nice. Thanks for the range report.

 

Good deal! A successful reloading and subsequent shooting session are all we ask for...
It sounds like your 4.7-4.8 gr is working well, quite honestly my powder throws in this regard are usually +-.1gr anyway, so I wouldn’t be too concerned if 4.7 or 4.8 was what you ended up with.
It’s difficult to get a measure of “smokiness”, but lower charges of powder may not burn as well as higher charges. You also may have some residual lube in the case that’s not consistent, and the bullets may also have some. As long as that doesn’t affect what you’re shooting for, no worries.
You may not be able to observe pressure signs until it’s too late, but, it’s always good to check and insure there are none. Good luck with the future reloads.