I have a 16" Tromix upper on the way (from their recent BLEM sale). It has a carbine length gas tube/system.

I have two lowers: one built for rifle length (A1-ish retro style) and the other for a mid-length modern upper.

My other lower has a basic adjustable stock, and what I've read is the pin can't take the recoil, so it often fails.

I've read a few conflicting things so I was hoping to get a clear answer on this. The wisdom of other forums I've seen suggests I should use the A1 stock because it will take the recoil. But I still have questions.

• Should I use the rifle-length buffer and spring with the A1 stock?

• Will the buffer spring of the rifle-length lower be too strong for the carbine length .458 SOCOM upper?

Took some time this morning to try loading my new trimmed brass with bullets only, no powder no primer, to test feeding. Left to right, Hornady 300gr JHp to 2.030 (bottom of the crimp grove), 300gr RNFP (Missouri bullet co Buffalo #2) same OAL, 325gr FTX to 2.16, Speer 400gr to 2.08, and 410gr MBC Socom to the crimp groove 2.012 I think. Lee bullet seating die set up for bullet seating only and FCD set up to remove the slight case mouth bell.

I loaded them in the following magazines: ASC 10 round (holds 3 as they come, 4 with the follower modified, I also cut a bit of the top lip down to ease feeding big bullets), Magpul P mag 20rd, and standard metal 30rd mags. All rounds fed and chambered from all mags with no signs of sticking or not fully chambering except the 400gr Speers that wouldn’t feed from the unmodified 30rnd mags.

Time to load up some test rounds in each size and see how it goes.

Putting together a 458 socom on an AR platform. I’m looking to use it for deer and black bear. Most shots should be under 100 yds. I’m debating between a red dot with no magnification or a fixed 4x scope. Hunting in heavy woods. Let me know your thoughts

I have no loaded ammo for the 458 currently so it was time to bite the bullet so to speak and get my brass cleaned and prepped. I was sitting on about 100 once fired and 250 new cases and got all of the 1x and 150 of the new processed. After sizing, trimming, and deburring 250 cases over the last couple days, I came away with some notes for next time.

Left is new, middle is new after sizing, trimmed, and chamfered, and right is once fired, sized trimmed and chamfered.

It’s been said before, here and elsewhere, but I had to be stubborn and learn it the hard way: New brass MUST be trimmed to length. Of the 100 1x cases, 80 of them were reloads that I had only sized the first time, not trimmed, and case lengths ranged between 1.575 and 1.580. I had a ton of problems with failing to chamber and stuck cases on my reloads that I originally thought were because I didn’t get the bell out of case mouths and now I think it was just leaving the cases too long. I measured a smattering of cases that I had sized and all were 1.575 so I thought I was good but from more reading and learning I realize now I needed to be down around 1.570 which is what I ended up trimming everything to this time. Fingers crossed that stuck case issue is solved with this.

I also tried Winchester LP (not magnum) primers for the last set of loads and had inconsistent performance, lots of unburned powder, and a couple hangfires running AA1680 with a variety of bullets. I’m going to try Federal LPM primers next time, and a couple other powders (CFE BLK, Lil Gun, maybe win 748) with the same bullet (undecided as of yet) to see what I get.

I'd love to build a 458 on an r700 platform but I've seen info that the magazines aren't particularly common or specially built; I've seen that 6BR mags might work, that the metal mags can be bent with a feed lip tool, and saw a few post where u/AllArmsLLC was working on a 458 specific mag.

What's the status of 458 mags for bolt actions in 2025?

Other than a pso scope this is the only magnified optic eye own, please don't be mad.

Hello. I am building a lower out for my 8IN .458 upper. Previously I had success with a standard carbine length with an H4 weight which was able to tame some of the recoil.

With this new upper I have a KAK 9 position (A5 buffer) ready to install. I have the A5 7.2OZ buffer weight however I am unsure if I should also get the red spring (Allegedly rifle length) to further reduce felt recoil. If I go for the red spring EVERY website I try to order from (Primary Arms for example) claims this is a carbine length spring. Am I mistaken for thinking that is too short to be reliable out of an A5 type system?

Am I insane for this one? Or should I just get a green rifle length and be done with it?

Anyone else running a 10.5” for pigs? If so what optic system are you running and why?

hybrid 46M not attached, but will be paired when on the field

So I’m posting this one again, because now she’s all done.

So after a call with griffin and being told that their tri-lug system can't be used with .458 they suggested the Gate-lok instead. I'm looking for an alternative to direct threading and was wondering if anyone here's used these yet. I'll have to put my birdcage back on but otherwise it seems like a promising system.

Trying to figure out what barrel length and profile to run with a can.

I’m wanting something like 8.5” or 10”. There’s a few different options, between barrel finishes and materials. But my main question is about the lightweight barrels.

Anyone have recommendations or some actual experience

Well, I finally got to go to the range with my new Garmin Chrono. I must say that I do like it much better than the one that I had before. Just wanted to share some findings.

A while back I picked up some Hornady 300 grain Interlock hollow point bullets but all of the load data was subsonic. I am not shooting suppressed so I don't care if they are running supersonic or not. Others have had success with starting with 325 grain FTX loads, so I used that as a starting point while seating the 300 grain bullets to the same depth as the 325 grain ones. I did 5 loads beginning with the starting load for each powder and chrono'd the loads. All loads were within a couple of hundredths of a grain and there were no signs pressure issues.

I was happier with the H110 velocities than with XTerminator. It also uses less powder.

Bullet Hornady 300 grain Interlock
Powder H110
Charge 26.0 grains
Stats - Average 1356.96 ft/s
Stats - Highest 1381.69 ft/s
Stats - Lowest 1320.97 ft/s
Stats - Ext. Spread 60.73 ft/s
Stats - Std. Dev 19.95 ft/s

Bullet Hornady 300 grain Interlock
Powder Xterminator
Charge 40.0 grains
Stats - Average 1212.65 ft/s
Stats - Highest 1244.01 ft/s
Stats - Lowest 1174.45 ft/s
Stats - Ext. Spread 69.55 ft/s
Stats - Std. Dev 23.1 ft/s

Anyone have BC data for some of the heavier projectiles? Or any projectile for that matter.

Was just over on the Tromix site and noticed blem complete uppers for $550.

Pretty good price if you're looking for a good 458 upper this holiday season.

Hi everyone.

Im looking to start a 458 Socom build. Not trying to spend crazy money on it but it needs to work without drama. I’m aware of Tromix and what they do. Can I pair a Aero XL upper and Aero R-One handguard with a Tromix barrel/bcg combo? I like the Aero uppers/lowers especially in coyote Tan.

Faxon 458 barrels any good? Should I avoid Bear Creek Arsenal 458 complete uppers ?

I also need a recommendations on a good muzzle brake that will not blow gas in my face. I see all kinds of threads for 458. Nothings seems to be standard. 11/16x24, 5/8x32, 5/8x24.

Im right hand left eye dominant but I dont buy left hand rifles. Anyone here shooting a right hand 458 with left side? Trying to see hows the ejection/blowback with the 458.

Thanks.

I ordered a blemished 8' tromix upper some time ago and still havent shot it yet. Are Tromix's good? I know it's suppose to be but anyone runing this upper have any issues with it?

Edit: Okay smart@'s sorry for the ' and not a "

Wanted to get everyone's opinion on what the best can is for .458 surpressed. Mostly using maker 500gr subs so sound reduction is priority. Not worried about dimensions of the can and am shooting out of tromix 10 in 1-10 twist. Will likely be getting a 16" bolt gun get the 650gr makers ad well.

Let me know your guys thoughts.

G'day, all. I put in an order to Scheels the other day and on a whim to get free shipping added 100 300 grain Hornady Interlock HP bullets. Surprisingly, Hornady doesn't have any load data for the 458 SOCOM on their app.

Hodgdon does have some loads listed but they are all subsonic. I've seen some folk on here using CFE BLK and they used the 325 Hornady FTX as a starting point. I do have this data from a book and have been reloading with H110 and X-Terminator.

Just looking for insights.

https://preview.redd.it/uzwm8pj9hn2e1.png?width=564&format=png&auto=webp&s=ffe8292ab516215f76b85cdeac8bd5dec7f2ff1f

Anyone else ever work on loads with these 300 grain bullets?

Started life as a Southern Ballistic Research (SBR) AR458 which I cant seem to find much info on.

Tromix billet upper (anodizing blem) Southern Ballistic Research lower Teppo Jutsu 16" barrel 5/8x32 thread Aero enhanced 15" handguard Ergo suregrip PRI A2 Stock PRI gas buster big latch CMC 2.5lb trigger CMMG upper completion kit Reptilia AUS 1.54" Zeiss conquest V4 1-4x24 Liberty Goliath

Just for clarification I do own a 46m which I know will work.

Since buying my first suppressor(30cal) a few years ago that I had planned to run across multiple platforms Ive managed to rack up a fairly decent stamp collection…so now days with a new platform it’s not do I have a can for it, more like what can will I buy for it. I was warned before getting into this game lol.

##2024 US elections ##Tuesday, November 5, 2024

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Can anyone tell my why or what the fix is for this sort of malfunction? It happens about every 5th round, I've tried all sorts of different Projectiles from flat point to round nose. They are all hand loads, but I've tried loading them longer, to shorter, gas settings. A slight pull and release of the bolt will usually send the round into battery, but its super annoying. Besides just going to a Troomix bolt I dont know what to try next. LANCER 20 round 458 cut mags, different gas settings ect. Any help would be awesome.

G'day all. Did some searches here rather that on r/reloading although I could pop over there too. It seemed more specialized here though. Saw some load data for H110, lil gun, and a few others. I am new into the heavier loads like the SOCOM shoots so I wondered if you had your go to powders for these ranges of bullets. I may end up with some heavier loads eventually but these were mid range and seemed to provide a good starting point.

Berrys 350 grain
Hornady 325 grain FTX
Hornady 410 grain SubX
Speer 400 grain flat point

Any thoughts on ShootersWorld SOCOM (Lovex D063-01) powder?

I reload a LOT (a pair of 750s and rockchucker) and have several powders that I use regularly for .223, .308 and 300BLK as well as most handgun rounds.

Thanks for any insights.

Taking Vera out blackbear hunting in Washington soon. :)

Got my little ACOG, got my 5 rd mags, got my 500gn rounds, got my suppressor, got my 10.5" barrel, got my paperwork.

Am v v excited.

That is all. <3

Hopefully I'll update with some pics soon.