I'm thinking about making a .458 SOCOM AR platform. Does anyone have any input on the reliability of the round, feeding or performance issues?
- Thread starter werthless_one
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And will a pmag or GI mag work for them?
I have not owned but have fired 2 at the range. One was a custom and the other a Rock River, neither had any issues feeding and both were accurate at the 100 yd range. All hogs shot from 50 to 200 yds were DRT (TX). I ended up with a 450 upper, as at the time I could find no ammo or brass, as was the case with the Beowolf 50.
Have one RR factory upper. I have only run SBR's factory ammo, and have had 0 misfeeds.
I had trouble with pmags, could only get a few rounds in, so I never dug deeper as to why. I suspect I'll need to do some dremmiling of the ribs inside the mag. I've used GI mags exclusively, and as above, no dramas.
What I like about the 458 socom cartridge, is it uses 45 cal rifle projectiles vs handgun projectiles that some of the other 45 cal cartridges use. (458 bore vs 452). This gives a nice selection of lighter weight 45-70 application projectiles, as well as the big-heavy stuff from the dangerous game side of the 45 rifle bullets. The light 45-70 side gets me 250-300gr that I can push at 2000fps+ that are nice for plinking or short-range deer/bear use. The big heavies get me 600gr for subsonic loads.
Its a nice add-on to your AR platform that really expands its usability.
I had trouble with pmags, could only get a few rounds in, so I never dug deeper as to why. I suspect I'll need to do some dremmiling of the ribs inside the mag. I've used GI mags exclusively, and as above, no dramas.
What I like about the 458 socom cartridge, is it uses 45 cal rifle projectiles vs handgun projectiles that some of the other 45 cal cartridges use. (458 bore vs 452). This gives a nice selection of lighter weight 45-70 application projectiles, as well as the big-heavy stuff from the dangerous game side of the 45 rifle bullets. The light 45-70 side gets me 250-300gr that I can push at 2000fps+ that are nice for plinking or short-range deer/bear use. The big heavies get me 600gr for subsonic loads.
Its a nice add-on to your AR platform that really expands its usability.
I love my 458 after I got the gun and my reloads working together. If you plan to reload and use pistol powder like H110, get a carbine length gas system. I have a mid-length that I battled with for a month with short stroking and over pressure. First it was on RRA end. The gas port wasn't drilled completely. I have a family friend who works at RRA so he took care of me. I ran the load of 29grs of Lil Gun behind a Hornady 325gr FTX and still had feeding issues and ejector marks. My magic solution was switching to rifle powder, IMR4198 to be exact. The pressure curve lasts longer and I haven't had a problem since.
I run GI mags that I relieved a bit at the front to ease unloading. It's a great thumper round.
I run GI mags that I relieved a bit at the front to ease unloading. It's a great thumper round.
I assembled one a couple years ago. Never purchased any factory ammo just bought a couple hundred of the Starline brass and made my own rounds. It fed reliable out of a Pmag and never had any issues with it. It was fun as hell to shoot but also really expensive to shoot (and reload). The round has crazy knockdown power but ballistically it's a turd, even worse than the 300 BLK. Like the Blackout it really shines in short range suppressed fire. If that is your goal then by all means you'll love it. I toyed with huntning with it since I belive it would make a killer short range brush rifle but I ended up trading it before deer season rolled around. Kickass rifle and round but limited in use. IMHO.
...its been said "If it bleeds you can kill it with a 458 Socom". That should be amended to include "If you're close enough to it..."
Feeds from GI's like corn through a goose and if you set everything up correctly it will go bang every time you pull the trigger.
I've built several for guys in TX for shooting hogs that havent complained. I wouldnt hesitate to take it into the dark timber for close range elk. Lehigh makes some interesting lathe turned projectiles in .458.
Feeds from GI's like corn through a goose and if you set everything up correctly it will go bang every time you pull the trigger.
I've built several for guys in TX for shooting hogs that havent complained. I wouldnt hesitate to take it into the dark timber for close range elk. Lehigh makes some interesting lathe turned projectiles in .458.
I have had a 458 socom for 7 years and it is a beast for its intended purpose . lancer magazines are the best to use no mods are needed for longer bullets .
Carbine gas is the way to go its allows more types of powder to be used . I have used the hornady 325 grain and 29 grains of lil gun with alot of success but the remington 300 grain hollow points are half the cost at 36.00 per hundred and kill every thing I shoot with them . with the 300 grain zeroed at 100 yds it drops 11 inches at 200 yds and 44 inches at 300 yds . barnes makes a 300 grain ttsx that is a horse of a different color it is designed for the socom and will expand at much lower velocity than alot of 458 diameter bullets but requires a lower powder charge than other 300 grain bullets do to its longer length . I recently saw a picture of a nice bull elk took at 197 yds with a socom .
here is a picture of 4 shots at 300 yds . 300 grain remington , 1850 fps I used a 10 shot bushmaster mag so 4 is all that would fit
Carbine gas is the way to go its allows more types of powder to be used . I have used the hornady 325 grain and 29 grains of lil gun with alot of success but the remington 300 grain hollow points are half the cost at 36.00 per hundred and kill every thing I shoot with them . with the 300 grain zeroed at 100 yds it drops 11 inches at 200 yds and 44 inches at 300 yds . barnes makes a 300 grain ttsx that is a horse of a different color it is designed for the socom and will expand at much lower velocity than alot of 458 diameter bullets but requires a lower powder charge than other 300 grain bullets do to its longer length . I recently saw a picture of a nice bull elk took at 197 yds with a socom .
here is a picture of 4 shots at 300 yds . 300 grain remington , 1850 fps I used a 10 shot bushmaster mag so 4 is all that would fit
Finding brass is one of the true downsides to the 458 Socom
Don't even consider the round if you're not a proficient hand loader. I've found that HK mags work the best for me and they'll hold 11rds reliably. Good 'ol GI mags work fine too(but I'm kind of a mag snob I guess). There is a plethora of bullets available and I personally have weights from 250grns up to 500. Think 600 is about max for that caliber. Buy your brass in bulk and a good variety of pistol powders too. This round takes a pistol primer though, so be aware of that. If you want to run Pmags, you'll have to remove the small pointed extension that stops the travel of the follower at the front of the mag. Once you do that, it won't lock the bolt back reliably, so don't fuck with your Pmags.
I picked up an RRA rifle about 6yrs ago and have about 500rds through it now. I really fucked up when I swapped on a collapsable stock and ran an AR10 buffer & spring(which allowed the bolt carrier to travel too far back into the buffer tube). That mistake caused poor ejection and ruined some of my brass. I also didn't realize I had high pressure signs and had to bump my H110 load back considerably. I torched my firing pin and it started piercing primers too. I've got all of that straightened out now and I'm very happy with it.
It's a freakin hammer though and you'll be impressed with the punch it packs. Heaviest I've shot so far is a 440grn Cast Performance. I'll have to look at my load book, but offhand I want to say I was getting 1500fps. Oh, and don't waste your time with Lee dies(which should be common knowledge around here). The only thing Lee makes that I'll own or use is their FCD(Factory Crimp Die). Yeah, I'm kind of a snob. Good luck with your choice though and be prepared to drop some dough on components
I've had good luck w/ steel and p-mags. You have to modify your mags (easy). FTX pills and reloader 7 work good for me. Been happy w/ the redding dies. It's good stuff and lots of fun. A 308 might be more appropriate across a bigger spectrum, but I have one of those too. Wilson Combat makes some nice billet receivers for it.
Love My rock river 458 socom. Shoots 1 MOA at 100 yards with factory corbon ammo. Never had any kind of issue.
Don't even consider the round if you're not a proficient hand loader.
The only thing Lee makes that I'll own or use is their FCD(Factory Crimp Die). Yeah, I'm kind of a snob.
Good luck with your choice though and be prepared to drop some dough on components
Ya I reload everything and completely agree on the Lee Dies. All I use of there's is FCD's. Really all I am needing is a barrel, bolt and my damn tax stamps to come back since it will be an SBR.
On another note, does anyone know if an AAC Ti-rant 45 can will work for a .458? Or do I need to pick up a different one?
I have two .308 bolt guns already. I am converting the scout .308 into a scout .338 whisper. I am looking to build a bruiser that compliments and shares the same mags as my 300AAC and AR's. I like commonality amongst my weapons. Not having to have 70 different kinds of magazines makes it nice, simple and efficient. That is also why I only have .45ACP 1911's(besides the fact that they are the best pistol platform I have ever used) or revolvers for pistols(love my Ruger Blackhawks).
So the consensus seems to be that pmags are not the way to go?
some guys use p-mags but with longer bullets the rib will interfere . I use lancer l5 awm mags and have no issues at all . I have infact switched to lancers exclusively for all my ar's 5.56 , 300 black and 458 socom . if all else fails just use G.I mags
Been doing 458 SOCOM since 13JAN02.
1) The original PRI 6.8 mags are my #1 choice with the new da-da-damn waffled fracked version being 2nd. BUTT!!!
Any GI aluminum is good to go w/teflon coat being a preference.
2) 458 SOCOM doesn't suppress worth a rats's hinnie. Big hole/low pressure round.
3) Many have brass on +15 reloads without annealing.
4) Redding Dies ftw
5) Imperial Sizing Wax
6) A Marty ter Weeme Case Gage is sweet or go Redding Die and no da-da-damn extra 1/8-1/4 turn after contact with the Redding shell holder OR!!!
do the Hornady Lock-N-Load Overall Length Gage thingie.
7) I only go with the various 300-325gr .458 boolits. H110 is my favorite powder for Accuracy w/Speed, but Re7 is mellower while being a very good choice.
Don't forget to head over to:
Teppo Jutsu - "Art of the Rifle" - Advanced Firearms Applications
www.458socomforums.com - Index
Best to you.
1) The original PRI 6.8 mags are my #1 choice with the new da-da-damn waffled fracked version being 2nd. BUTT!!!
Any GI aluminum is good to go w/teflon coat being a preference.
2) 458 SOCOM doesn't suppress worth a rats's hinnie. Big hole/low pressure round.
3) Many have brass on +15 reloads without annealing.
4) Redding Dies ftw
5) Imperial Sizing Wax
6) A Marty ter Weeme Case Gage is sweet or go Redding Die and no da-da-damn extra 1/8-1/4 turn after contact with the Redding shell holder OR!!!
do the Hornady Lock-N-Load Overall Length Gage thingie.
7) I only go with the various 300-325gr .458 boolits. H110 is my favorite powder for Accuracy w/Speed, but Re7 is mellower while being a very good choice.
Don't forget to head over to:
Teppo Jutsu - "Art of the Rifle" - Advanced Firearms Applications
www.458socomforums.com - Index
Best to you.
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When I was trying to decide whether to build a 458, a big issue for me was that I couldn't find barrels with the twist that I wanted. Many barrels are 1:14" twist, meaning they tend to shoot the heavier bullets better. I couldn't care less about heavier bullets for this rig. I wanted to shoot the 300gr TSXs so I was hoping to find a 1:22" barrel. That has proven to be very difficult. Until I can build the upper that I want, I didn't move forward with the project. Just something to keep in mind.
It AIN'T the mass you're trying to stabilize, Bubba.
300gr Rem HP vs 300gr Barnes TTSX:
Now, go get that there 1:14" piece of pipe and start having some fun.
BTW, there AIN'T a .458 boolit that is going to be over-stabilized by a 1:14" pipe.
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Alas, forgive my imprecise language. It's not so much the stabilization that interests me, but just the overall efficiency of the combo. Bill Wilson's written about using 1:22" over 1:14" barrels for the Hornady hunting bullets. I defer to him on this as he's done the testing, and I haven't. I'm sure the 1:14" does just fine, but I'm a bit particular when I'm dropping so much on a new upper. To each his own.
If you go Billy's route, demand a picture of the latest 458 SOCOM barrel extensions before you purchase. If it looks like the ones on his website, he's still doing it wrong.
Just finished putting together a Wilson Combat 458 Socom kit! Have not had a chance to shoot it yet, will keep you informed.
Barrel 14.7" 1/14 twist, Lancer 20 & 30rd mags.
Barrel 14.7" 1/14 twist, Lancer 20 & 30rd mags.
How about a pic looking down your upper receiver towards the barrel extension, in full focus?
BTW, The latest pic of the 6 o'clock lug, on Billy's site, seems to still be missing a locking lug.
For those in Rio Linda, that's a RFA: wRong Fucking Answer. Even at a lowly da-da-damn 35K psi.
BTW, I wish to purchase one of Billy's .458 SOCOM 16" Heavy Barrel Kits. Just AIN'T gunna do it, rat da-da-damn now... till that 6 o'clock lug comes back.
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Ya let me know how it goes. Throw up a pick of your grouping when you get a chance.
I only have a couple pounds of lil gun but have 20lbs of H110(love that stuff). I will check out the ballistics on them for that round. Im just glad to hear that the effective range is better than 150yds. That is what everyone has been telling me. That is definitely a good grouping for 300yds. What barrel do you have on it? I'm debating on whether or not to make it an SBR. If I can't use my ti-rant that I already have then I won't go SBR. AAC says it won't be warrantied if I put it on a .458 SOCOM.
I haven't looked at reload prices yet. If it is expensive to shoot then I won't build one. Im building a .338 whisper out of my scout .308 ruger because it uses .308 brass that I have quite a bit of. I like making new platforms but not if it isn't feasible to shoot it. Did you have yours suppressed?
Ill see if i can get the pics to come out and post this week, and hope to shoot this friday!
The wilson combat barrel I had from a year and a half ago had the 6 oclock lug. Supposedly my barrel was part of the first run aftrr he added the 6 oclock lug intonthe barrel extension. My barrel extension from circa december 2012.How about a pic looking down your upper receiver towards the barrel extension, in full focus?
BTW, The latest pic of the 6 o'clock lug, on Billy's site, seems to still be missing a locking lug.
For those in Rio Linda, that's a RFA: wRong Fucking Answer. Even at a lowly da-da-damn 35K psi.
BTW, I wish to purchase one of Billy's .458 SOCOM 16" Heavy Barrel Kits. Just AIN'T gunna do it, rat da-da-damn now... till that 6 o'clock lug comes back.
Now if only I could find another kit. Never shoulda sold mine. Has anyone got their wilson combat kit lately?
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it is just a standard rock river carbine barrel nothing fancy . the only reason I tried 300 yds was because I was told I could not hit the broad side of a barn at that range with a socom I done it several times just to prove the first was not a fluke . 200 yds pretty well covers my shooting reguardless of caliber simply because of where I live the terrain dont allow farther shots .
Im not sure how well it will suppress since dave already stated big hole and low pressure . I seriously doubt it would be as quiet as my 300 blackouts .
I have a Wilson upper. Using Lancer mags exclusively for this platform. Hornady 325gr projos over IMR4198. No issues in feeding, cycling, etc.
Last 2 deer seasons: 4 shots. 4 deer.
I love this caliber.
Starline Brass will usually run a production once or twice a year. If you see it grab it while you can.
The main limitation in my opinion of this platform is that you need to be a hand loader.
Last 2 deer seasons: 4 shots. 4 deer.
I love this caliber.
Starline Brass will usually run a production once or twice a year. If you see it grab it while you can.
The main limitation in my opinion of this platform is that you need to be a hand loader.
I ordered my kit Dec. '12 and received it Jan '14, about 13 months, I ordered a 458 SOCOM Whisper from them at same time, have not heard if it is shipping soon, plan to call next week.
Have had a chance to get the pics of extension,
As for ammo I ordered last year from Wilson and SBRammunition. Just received a tracking number from SBR saying it will be here next week, can't wait, I will have pictures and range report(chrono, and accuracy) if weather holds for next weekend.
Have had a chance to get the pics of extension,
As for ammo I ordered last year from Wilson and SBRammunition. Just received a tracking number from SBR saying it will be here next week, can't wait, I will have pictures and range report(chrono, and accuracy) if weather holds for next weekend.
Here it is
Thanks to all for showing pics of the 6 o'clock lug coming back in style.
