.458 SOCOM anyone?

Sig556r

Active Member
458 socom is a fun round. I've been playing with a pointy(ish) bullet in the 458 socom doing some fun lobbing lead at steel. I want to try to take it out to 500 yards or so and see how it does.


And congrats, Ian with the future kid--I have four kids with a set of identical twins in the mix. It can can get crazy at times, but it's lots of fun too. I love it when we go as a family camping or shooting or whatever. Mine are all old enough now that I can take them shooting with me if they want to go. My oldest daughter is a great shot too.
Hi FLT, got hooked on your channel lately as I start to venture on 458 & can't help replaying a lot of them. Can't believe you only got so much followers with hi-quality informative videos.
Anyways, been casting & PC'ing .459 bullets (RCBS 45-300-FN & Lee 459-500-3R) & wondering if you have any advise on loads for RL7, 4198, 296 or 1680 (I know 5744 can be messy) since I don't have quickload at the moment. Just built a 16" carbine-gassed AR upper that cycles dummy rounds for both bullets. Planning on tinkering with Lyman (50th ed) published subsonic loads for Hornady 500g jacketed SP & supersonic loads for 300g jacketed bullets, but would be glad to hear from the experts.
TIA
 

popper

Well-Known Member
See All sight Be sure to get the pyramid reticle. You still have to figure your own hold over and the bottom of the sight obscures the target. No parallax at all. Worked with a guy few years ago that went Socom, had a fish/rice paddy near Gonzales. Said it worked great. Last itme I saw him he was shooting greased cast - Hornady was too much $.
 

Full.lead.taco

Active Member
I'm using the 500 gr NOE pointy bullet I designed, and I'm running it with 22gr of imr4198 in my 10.5" barrel. For my coworker's 16" barrel, we are using the same bullet with 22.5 gr of imr4198 to cycle better. Not sure if those loads will work with the lee bullet or not. As far as the 300gr bullet goes, I will have to go and check my load notes. I believe I was running an Accurate mold that was modified to take the lube grooves out which was a 300 gr bullet (pc'd with gc)--but I was using a hard alloy and the bullets were coming out at around 270gr. I believe I was using 37.5 gr of imr 4198, but that load you will want to double check before using.

Hi FLT, got hooked on your channel lately as I start to venture on 458 & can't help replaying a lot of them. Can't believe you only got so much followers with hi-quality informative videos.
Anyways, been casting & PC'ing .459 bullets (RCBS 45-300-FN & Lee 459-500-3R) & wondering if you have any advise on loads for RL7, 4198, 296 or 1680 (I know 5744 can be messy) since I don't have quickload at the moment. Just built a 16" carbine-gassed AR upper that cycles dummy rounds for both bullets. Planning on tinkering with Lyman (50th ed) published subsonic loads for Hornady 500g jacketed SP & supersonic loads for 300g jacketed bullets, but would be glad to hear from the experts.
TIA
 

358156 hp

At large, whereabouts unknown.
Ian, if you were going to build another SOCOM now, what might you do differently? I'm asking because I ran into a great deal on a mostly complete SOCOM bare upper, barrel, and bolt yesterday, and so my next project now lays before me. My barrel is 16 inches, and I'll be running a muzzle brake on this build to start with, the barrel came with a tank brake, but I already want something different. I also really need to break down and start buying cans for some of my guns, but I'm still trying to recover from my great sell-off a few years back, and can't seem to be able to say "no" to anything, money permitting, and thank you for the roadmap to get me started off on the right foot. Too bad we don't have piggies up here, or maybe not so bad after all. The guys I play with would turn into total hunting bums with such an opportunity. I know our farmers certainly wouldn't be happy if pigs made it to Nebraska.
 

Ian

Notorious member
Now that I have a lathe, I would probably make the barrel extension out of aluminum and turn a nice aluminum bushing to fit it to the barrel. TiG it all together, pin it, and float a puddle over the pins. That would save a little weight, even though it isn't very heavy as it is. Other than that, the only thing I can think of that I'd change is simply to add a good quality red dot sight, maybe a Holosun unit.

With the suppressor and 500-grain subsonic loads, my rifle kicks like an 870 12-gauge with high-brass 1-1/4 oz. slugs, I never shot it without the suppressor, and wouldn't want to! I'd keep whatever brake it comes with, and be aware that the threads are probably proprietary unless they're Tromix (Tromix uses 30-cal threads, 5/8x24). The tank brake is on there for a reason, these things in an AR platform will wallop you pretty hard.

I did a lot of research before buying this and found no real surprises along the way. I wouldn't buy any parts other than Tromix or Teppo Jutsu, the reamer prints are still proprietary and as far as I know the other outfits like Radical and CMMG aren't necessarily making proper chambers. Doing this will save you a lot of headaches later. If you get a Tromix upper receiver it will be ready to go, if not, I can give you dimensions and such to modify the ejection port so the cover will still latch properly yet never give you a jam. Marty posted some dimensional drawings of the port mods on arfcom, you can go off of that but it isn't necessary to cut the top of the opening out as much as he does. Other advice I have is to buy some Lancer magazines, nothing else works as well for me (Lancer sucks for everything else BUT the SOCOM, IMO, nothing but troubles with the feed lips due to a very unfortunate engineering oversight on Lancer's part, but that's another story), and buy a Tromix case gauge for setting up and checking your loads.....the SOCOM set up to shoot cast bullets will have benchrest match chamber/cartridge tolerances and it being an AR-15 with weak-assed self-loading and bolt camming action you'll want to make certain that every round will chamber after you load them. The cutaway case gauge is expensive, but priceless for seeing how things fit and for establishing bullet seating depth, crimp process, and for observing interferences. I use Lee dies but had to make a larger and longer expander plug for the PTE die in order to use cast bullets. I also honed the neck of the sizing die a few thousandths, not easy since it is a blind hole, but necessary for cast. The cartridge cannot stand to have the neck and body not concentric, so the best way to keep them that way is not to over-size the necks in the first place.

If you dive into this, start a build thread and put up some photos if you can, I think you'll love the caliber and the platform, I know I do. I'm already wanting a second one in pistol configuration now that there are some much better arm braces available.
 
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jdickey

New Member
Hello all,
You all seem to have a vast wealth of knowledge on casting and 458 socom, I would like some pointers! I'm putting together a 458 over the next year, I'm filing a few tax stamps for it so there is no hurry on buying stuff for it soon. Current plan is suppressed sbr. Major components are10.5" in 1:10 twist tromix barrel, tromix bcg, bowers v458 can.

Obviously I'm planning on using this to hurl massive chunks of subsonic lead. I've been reloading for 10 years, a mix of bought cast and jacketed on multiple pistol and rifle platforms, so am looking to start buying components. Starline fresh brass number 1. I realized how expensive that chunk of lead would be I kind of stepped back and started looking at casting as well. IMHO a man never has enough hobbies, especially if it has something to do with hurling lead.

If I cast I'll go big operation. rcbs pro melt 2, accurate or similar quality steel die, I was thinking hardball or lenotype lead would be fine for these large grain 1000 fps bullets.

I've got a lot of questions and I'll probably have more but any guidance I could get as a fng to 458/casting is much appreciated! Questions are:

Is anyone using this specific tromix barrel and can they recommend or link me loads that cycle well on this platform?

Can you recommend off the shelf bullets for this platform?

If I cast, what type of lead should i use? Was thinking lenotype or hardball. Is a softer lead ok?

If I cast I'm planning on powder coating, but what are your preferences and why? I would think PC would be less likely to lead up if done right but what's your experience?

Do you have a recommended steel die manufacturer? Make for large grain bullets? Ideally without lube grooves if I PC.

If you powder coat how much smaller do you design your mold? How much does PC add?

Already cast, large grain bullets were running just shy of $1 a bullet. How much does PC cost, roughly, per bullet? I'm guessing lead costs for lenotype to be around $.28 a round, so if PC is cheap enough I could save roughly 2/3's on rounds. And be self sufficient if the round dies....

This is the short list that comes to mind. I'm sure I'll have more questions. Will keep you all apprised of progress for your help!
Dickey
 

Full.lead.taco

Active Member
@jdickey
I'd say buy the Redding dies, you will not regret them. Also, pick up a Tromix slotted case/ammo gauge--it will help you when figuring out seating depths and troubleshooting of your ammo. As far as bullet molds, I'm a little partial to the one I drew up for the 458 socom that NOE produced. It works well for me--casts great, coats great and shoots great. It is the NOE HTC459-500-SP mold. Hardness wise, you don't need super hard bullets for the 500 gr subs--wheel weights work just fine. Powder coat powder wise, I really like and get great results with the powderbuythepound.com "glass clear" powder. Don't start with Harbor Freight powders--high quality powders don't cost that much more, but they work that much better. 1 LB of PC powder lasts forever it seems... Get a lee push through sizing die or an NOE push through sizing die for cheap and easy sizing of powder coated bullets. Don't be afraid to use a little case lube on the bullets when sizing if it feels tight or like you have to push hard on that handle. Feel free to ask if you have questions as they come up. Ian also does a bunch with 458 socom too, so he will probably add what he thinks.
 

Ian

Notorious member
I pretty well reviewed what I'm doing in the thread, give it a read.
 
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jdickey

New Member
@Full.lead.taco
Thanks for the info! I'll definitely get the Tromix gages. And your mold! Initially I'm planning on getting lead-alloy ingot. I'm sure I could find cheaper lead sources, and will look into it as I get casting experience. But initially I'm going to try and control as many factors as I can as I learn to cast. That being said, do you have any insight on how soft (rough brinell hardness) I could cast a subsonic bullet and ensure no leading? I also understand PC helps stop lead from occurring? Again, just trying to choose a lead alloy ingot to start with.

@Ian
This thread is very informative! I'm ignorant with regards to casting and was hoping to get more details. I know sizing is critical. And from what I've read lead selection, die selection, casting, PCing, sizing, etc. can significantly alter the diameter and make a bullet out of the same die usable or unusable for a given round depending on your process... Or at least that's what I've read, maybe it's not that finicky. If I can follow someone's known recipe I'll be less likely to fail I hope.

As I go down this road if I have any more specific questions or issues I may reach out on this forum, thanks again for all the helpful info!
 

Full.lead.taco

Active Member
More often than not, leading is caused by bullets which are not sized to fit your barrel (ie: undersized bullets). Going subsonic in a 458 socom, you are actually pretty low pressure--I'd bet that you could take pretty soft lead and still have no leading. Powder coating is almost a must, however, when shooting suppressed. You don't want that traditional lube to cake up on your suppressor baffles.

@Full.lead.taco
Thanks for the info! I'll definitely get the Tromix gages. And your mold! Initially I'm planning on getting lead-alloy ingot. I'm sure I could find cheaper lead sources, and will look into it as I get casting experience. But initially I'm going to try and control as many factors as I can as I learn to cast. That being said, do you have any insight on how soft (rough brinell hardness) I could cast a subsonic bullet and ensure no leading? I also understand PC helps stop lead from occurring? Again, just trying to choose a lead alloy ingot to start with.