Building a hunting AR 15

[Swamp Fox]

I want to build an upper for my AR in a hunting level caliber. Use will be for deer and hogs, at less than 200 yards. In all reality most of my kills have been closer to 50 yards than 200, or even 100. Looking at it I have been primarily considering 6.5 Grendel, 450 bushmaster, and 458 socom. I like big slow moving bullets with good knock down power, so I’ve been leaning towards the 458, as I think it has some advantages over the 450. But it is so much more expensive to buy factory loads for, and in the end I think one or the other caliber will win out, and it’s looking like it will be 450 BM. The 6.5 doesn’t seem like a bad choice, but it seems more suited for longer ranges and the bullets are on the light side of what I would be comfortable with. But I’ve seen some deer killed with them and no problems.

Any body have any advice or things to consider? Or want to talk me into another caliber? I know people will say 300 blackout, but it just doesn’t impress me. Once I decide on a caliber I’ll have other questions but I need to pick one first.

[Nobade]

Wilson's new 300 ham'r. We've been playing with their 7.62x40 with great results, and the new one is just more of the same. And it makes a way better cast boolit gun than a 6.5 does.

[Rcmaveric]

Cast bullets work in all those calibers. Anyone of them will do it. I have a Grendel and built it too heavy. I plan on the building a new one with an 11 twist 21 inch barrel. I also plan on building a .277 Wolverine.

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[Smoke4320]

I have both the 6.5 Grendel and a 458 Socom
the socom would be my choice for anything under 150 yds .. Its big, its bad and nothing walks away from a well placed hit
there are multitudes of bullets designed for the 45-70 and will move to the socom no issues Bullets ranging 180 gr (color button) to well over 500 grns

Mine loves the RCBS 45-300 the NOE 460-350 HP and for subsonic the Lee 500 grn pointed

[Moleman-]

450bm has a lot going for it. Works well with cast, can be run subsonic or standard, and there is factory ammo available should you be away hunting and have a need for ammo....

[Texas by God]

6.8 SPC kills way out of proportion to its size. I am an eyewitness to this phenomenon. Having said that my latest project is a 6.5 Grendel. I have a 300 Blackout and I consider it to be the equal of a 357 Magnum carbine. Although I wouldn't mind having one of each, the 450 Bushmaster and the 458 Socom wouldn't get much use where I live.

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[popper]

If you have carbine lower you have to go carbine (16") to be legal and suffer the weight penalty. My pig gun is 10" BO pistol with 185gr RD style cast, 1700 fps? Not sure what the FN boolit gr. limit in the 40WT or Hamer is. Guy I worked with got the BM or socom, don't remember which for pig hunting. He's a big guy and didn't like shooting a lot of rnds at the range, very accurate @ 50 IIRC.

[fredj338]

My hunting ar is a 6.8spc. I like the round, hits quite a bit harder, on steel anyway, than an 223. Recoil is also quite soft.

[nannyhammer]

Another vote for the 6.8 SPC. I run 100gr Accubonds at about 2850 and they work just fine. Have killed deer, pigs and coyotes and have no reason to change for my hunting needs.

[pertnear]

+1 for the 6.8mm SPC II.

It has become my favorite whitetail rifle.

[rockrat]

I would go with the 450 Bm or even the 7.62 x 39. I have the Grendel also but since hogs are in the mix, the 450bm. Quite accurate

[Swamp Fox]

Seems to be a lot of people liking the 6.8. I’ll have to do some research on them. I thought it had become less popular since the Grendel came out.
I have the most trouble between the 450BM and the 458. I like the 450 because it’s got a better selection of lighter billets, and it’s much cheaper to buy factory ammo for. But it headspaces on the cartridge mouth, so no roll crimps. On the other hand, the 458 can share bullets with my 45/70. And it can run on standard mags. Really there’s probably not a bad choice in the bunch. Everybody seems happy with whatever they have. That just doesn’t make the choice any easier.

[dkf]

The .450bushmaster is a SAAMI cartridge now, the .458socom was submitted but since Remington and the big companies sit on the SAAMI board it is unlikely it will go anywhere with them soon. The .450 bushmaster is cheaper but several of those factory loads have bullets that are soft and will even come apart really quick in a deer. The .458socom has more companies loading for it and a much broader array of ammo available for it than the .450. There are more .458socom specific bullets available for it as well as 45-70 bullets that are designed to be in the velocity window of the .458socom. The .458socom also doesn't have problems with rounds riding too high and popping out of the mags either like the .450 does.

[pmer]

I went with the 458 SOCOM and had it hunting with 405 grain Marlin boolits going just over 1600 FPS. It groups this load like no problem. If you go this way get the Tromix. I thought I'd save some money and get a lesser known brand. I had to work through light primer strikes, feed troubles and case neck turning because my chamber neck is pretty tight. The Tromix chamber utilizes a bigger chamber neck than what mine has and should be much easier to work with.

[Marine Sgt 2111]

Well I built a 6.5 Grendel and for Pure accuracy and distance it will surgically plant a bullet in any animal out to 300 yards quite comfortably. But I also recently bought a 450 BM upper, and I have to tell you right out of the gate it will have three holes touching at a hundred yards all day long. It shoots Hornady 250 grain FTX a 2140 FPS out of a 16 inch barrel with all holes touching at a hundred yards. About the only thing I don't like about it is the one in 24 twist. But whether it's my Ruger number three in 45-70 with a 1 in 20 in twist are my Shiloh sharps with a one in 20 twist also in 4570, so I guess the one in 24 twist isn't that bad a handicap. I've shot mine and I've shot another rifle in 450 BM and both of them will shoot 1 inch Center to Center at a hundred yards. In Michigan we have to use a straight walled case if you want to hunt in traditional shotgun and handgun areas. And if you look, the 450 BM usually has more energy then the 458 Socom.

[BigBore45]

7.62x39. Cheap. Available. Roughly 30-30 ballistics.

[crankycalico]

450 bushmaster... just a wonderful cartridge. It can create wounds that scare the **** out of game processors who have customers hunting with 300 win mags.

[DougGuy]

If I wanted a hunting AR, I would seriously investigate the Wilson 300 Ham'r. Bill Wilson himself kills tons of hogs on his Texas ranch, he has probably tried every caliber that you could cram into an AR magazine, and the 300 actually outperforms the vaunted and trusted 150gr 30-30 cartridge by a notable margin.

https://www.americanhunter.org/articles/2018/8/21/review-wilson-combat-300-ham-r-cartridge/

Then again, I can always drop a 150gr load in my 300 AAC and hunt with that, at 1900fps it's marginally slower than the 300 Ham'r but deer or pigs wouldn't notice if hit in the right place.

[Swamp Fox]

The 300 hamr looks interesting as it fixes my gripe with 300 blackout, aka not enough power. But will it ever catch on? I don’t want to buy something that I won’t be able to get ammo for in 10 years. Although really I guess I’d only be out the cost of a barrel

Looking at the 6.8 spc stuff now, but it seems harder to find than a few years ago. Seems like a great round though.

450 BM seems like an easy answer though. You can get lighter, flatter shooting bullets than for 458. And it seems to be catching on.

So many good calibers....

[DougGuy]

I would only handload for the 300 hamr anyway so I wouldn't be concerned with store ammo.

Ok, I think this needs airing.. Consider the hard limitations for the AR. 1st and foremost, magazine length. No matter what the load it still has to cycle through the mag.

2nd, in the last what 20yrs, there have been hundreds of "new" rounds invented for the AR that are all a compromise between case capacity, and boolit weight, in all the calibers.

So... You keep going up in power until you have maxed out the curve under xxx grain boolit, so you go larger with diameter and heavier. Once again the curve starts and it keeps getting incrementally improved until the max energy can be pushed out with xxx boolit weight in the caliber. Not too hard to follow this process..

Ideally you would want to arrive at the combo that suits your needs the best. For some nothing smaller than 45 caliber will do, for others anything 150gr ~ 175gr in 30 caliber will do, and the sweet spots are many.

You can take any boolit diameter, and you can look at the myriad choices of case sizes and wildcat names. Eventually you will see that this entire AR game is broken down into "tuning and tweaking" the individual boolit diameters until the most efficient combo is reached in that caliber.

Basically, at this point in time, you can pick your caliber and then go find the best case scenario (pun intended) and buy dies, brass, and powder and a barrel and you are up and running.

Straight walled cases with 5.56 breech face would allow the biggest boolits, 40 caliber and above, but now you basically have the BC of pistol boolits, and ultimately the laws of physics will dictate trajectory, which establishes effective hunting ranges for the round.

Bottleneck cases will let you use rifle boolits which have a better BC and a better trajectory which stretches the effective range for the round.

If I got out my old crystal ball and rubbed it a time or two and asked what the optimum 30 caliber round would be, I am sure the answer would ring very close to one or more of the better 30 calibers out there now, like the 300 Ham'r.

[centershot]

If I wanted a hunting AR, I would buy a .223 Remington in whatever configuration I was comfortable with (barrel length, stock, etc.) and feed it Federal's Fusion load. For the last 5 years I have used that load to kill my deer and all have been one shot stops. A 62 gr. bonded core softpoint, muzzle velocity 2960 from my Ruger American, it kills all out of proportion to what it is. But, kill it does! Example - Last year, shot a nice 6 point at around 60 yards. He was angling toward me, walking slightly uphill, the bullet broke the left leg, entered the chest and broke a rib going in, destroyed both lungs, broke a rib going out, THEN broke the right foreleg AND KEPT GOING! You can not ask for more from a bullet than that! It looked like I had shot him with my '06! I know a lot of people will poo-poo the thought of shooting a deer with a .223, but, this load just plain works!

[DougGuy]

I know a lot of people will poo-poo the thought of shooting a deer with a .223, but, this load just plain works!

Many states have minimum caliber restrictions, you couldn't hunt with that in Virginia, 25 caliber and up.

[Gtek]

Latest build is a 450BM, Mid gas 18" with full length Ace stocked lower, 2x7 Leupold. Have not loaded any for this yet but the factory fodder is silly accurate, very happy with it. Clicked average of 2215 over chrony with 250's, more than enough for the Florida Bambi and Piggy.

[Texas by God]

With all due respect to Bill Wilson, if I load my 30/30 Winchester to the same pressure level as his 300 Hamr I don't think the difference would be that close anymore. Case capacity, pure & simple.
The .30 Rem AR cartridge was supposed to be the end-all for AR cartridges, but it died a quick death, didn't it?
Doug Guy nailed it on Post Number 20.

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[pmer]

https://tromix.com/product/375-socom-light-weight-barrel-bolt-combo/

Here's to slinging medium sized chunks of lead over 2000 fps. Has anyone tried the 375 socom? Looks like an easy neck size from 458 socom.

[Swamp Fox]

Pmer- that looks like what I want. A good all around load with respectable power. Looks like an ar version of a 35 rem. Too bad it’s so obscure. I wonder how much brass I would need for a lifetime supply?
Does anybody have one?

[willicd76]

Step up to the ar10 and a 358 Winchester!

[dkf]

Pmer- that looks like what I want. A good all around load with respectable power. Looks like an ar version of a 35 rem. Too bad it’s so obscure. I wonder how much brass I would need for a lifetime supply?
Does anybody have one?

I can get 20 loads easy with .458socom Starline brass. The .375socom is at the same pressure as the .458 so brass life should not be that far off. The .458socom brass is going to be around a while so you have that option. Have to full length size .458 brass to make .375 brass. SBR, Black Butterfly and Strike Force makes several .375socom loads. Tromix and Wilson Combat are working on an agreement with the .375socom so they will probably have rifles and ammo available at least. It should continue to grow in popularity.

[jeffsmith13]

I have several Ar rifles and pistols, AR15 and AR10. My favorite is the 7.62x39 and it is the cheapest by far to shoot . 300 Blk I traded off , the x39 will do all it does and do it cheaper. Subsonic sucks in 300 blk. Shoot super if you hunt with it. I hog hunt and most shots are under 100 yds. 255 gr hardcast 45 acp loaded with Ramshot enforcer in an AR upper will take deer and hogs in pistol range .

[Walla2]

Wilson's new 300 ham'r. We've been playing with their 7.62x40 with great results, and the new one is just more of the same. And it makes a way better cast boolit gun than a 6.5 does.

That is what I think will meet your needs. Wilson's 300 Ham'r.

[dh2]

I have a few AR-15 uppers the 300 Blk out does not impress me ballisticly ,for but easy to reload scrape range brass with wheel weight boolits.
the 6.5 and 6.8 both do well on deer, but the area I hunt Black bear is in for most of deer season, I don't feel they are up to the job.
.458 SOCOM I built one using a Wilson kit, my best results have been using Hornady leverlountion bullets made to load the 45/70 they preform well and for brass I just order Starline , most of my guns have never fired a factory round any way.

[jeffsmith13]

300 hamm’r gains 200 FPS over x39 according to Wilson’s numbers, lots of money for minimal gain . 458 socom is my next upper build, I already reload for 45-70 so it makes sense for me. 458 will reign supreme under 200 yards, sub or super.

[Swamp Fox]

I’ve got to say thinking all this through has been an educational but lslightly frustrating process. At one point I was writing out a chart comparing bullet weights, velocity and energy. Overall I have learned that there are a lot of good choices, but no one perfect caliber.
Below I’ve included a few of my thoughts on some of the choices, to hopefully help anybody else considering the subject. All should be able to be made to work with cast bullets, but I’ve not gone into that here. Any of these calibers are going to cost roughly the same to build, if using similar quality barrels. This makes ammo and component cost the prime practical cost, along with a few calibers needing dedicated magazines. After thinking about my uses, I decided to only consider 30 caliber or larger.
300 Hamr- a good step up from 300 BO. Not much more powerful than 7.62x39, but available with heavier bullets. Factory loads will shoot 150 grain bullets at 2200 FPS. There are limited options for factory ammo, but cost is inline with more common calibers. Being 308 diameter, there is probably the largest bullet selection of any caliber.

375 SOCOM- Perhaps my favorite load of this group, but has a lot of drawbacks too. Factory loads will move a 200 grain bullet around 2200 FPS, basically a semi auto 35 Remington. Great all around cartridge. The problems here are that only a few factory loads are available, and $2.50 a round. Even bullets have a limited selection and run around $1 per bullet. No factory brass available, you have to neck down 458 socom.

450 Bushmaster- Good factory ammo availablilty for reasonable prices. Will shoot 250 grain bullets to 2200 FPS. $1.25 - 1.50 per round. Plenty of bullet selection for good prices. Gaining in popularity and availability. Only real drawbacks are that it’s probably a little much for deer, and needs it’s own magazines.

458 SOCOM- Just below 45/70 performance, and with similar drop, making it a little harder to use at 150+ yards. Decent factory loaded ammo availability, but still $2.50 a round. Brass is available and 458 bullets are easy to come by. I think it’s an overall better cartridge than the 450, with heavier bullets available and head spacing on the neck so you can roll crimp.

[mto7464]

6.8 spcII. My son has 4 one shot kills with it using federals fusion bullets. Great rifle for hogs too.

If a shorter barrel is what you want, which I did, the 6.8 performs better. Mine is a 16 inch barrel and the Grendal likes the longer 20 inch.

[joel45acp]

Hard to beat an AR chambered in 6.8SPCll for deer, yotes or hogs. I'm very impressed with my Radical Arms 6.8. It'll shoot MOA or better with the Hornday 110gr HPBT pills at just over 2650fps.

[jmort]

I am good with the ACC 300 Black Out
It works just fine out to 200 yards supersonic and shoots heavy subsonic bullets
The current Mihec group buy on the heavy subsonic 300 BO HP is exactly what I want. Just depends on what you are looking for.
The 300 Blackout is here to stay.
The 300 BO Federal Fusion 150 grain is designated for "Big Game" by Federal

[Swamp Fox]

I looked at the 6.8 and liked it. I just decided for how I hunt to consider 30 cal or bigger. What can I say, I like heavy bullets that make big holes. Now that I say that it makes me wonder why I’m trying to hunt with an AR to begin with.

[Mr_Sheesh]

I'm wondering how a 7mm T-C/U stacks up for the AR15, and 7-30 Waters for the AR10 platform maybe?

[Lloyd Smale]

wish there were 300hmr and 6.8 complete guns as cheap as you can buy 5.56 and 300 bo guns. If some place like palmetto would jump on the bandwagon and make them id be one of there first customers.

[jonp]

I'm leaning towards the 450BM for a couple of reasons most the same as the ones I lean towards 5.56 derivatives in AR's. You can use the same magazines so no need to buy all new ones. Factory brass from Starline (tons of 5.56 out there dirt cheap for conversion to whatever you want like 300BO).

It is a solid 200yrd pig and deer gun which is what I gather from reading up on it and that seems to be the extreme range most shoot pigs at. It's also the distance you specifically mentioned in the op. Any farther and a true rifle caliber would be more appropriate, I think.

Considering the distances you mentioned, specifically that you shoot mostly under 100yrds, is there some reason you don't think a 300BO would work well enough or do you just want something different.

I've never shot either the 450 or 458 SOCOM. Out of an AR platform I'd think both would be quite a handful and I'm not a recoil fan. If I can get the job done with a smaller caliber then I'll do it every time

[jmort]

"I'm leaning towards the 450BM for a couple of reasons most the same as the ones I lean towards 5.56 derivatives in AR's. You can use the same magazines so no need to buy all new ones. Factory brass from Starline (tons of 5.56 out there dirt cheap for conversion to whatever you want like 300BO)."

Please correct me if I am wrong, but it is the 458 SOCOM that uses standard mags without changing anything and the 450 BM that requires its own specialized single stack follower. Starline has them both covered. I like the SOCOM if I am going big.

[jonp]

Your right, a slight mod to the magazine for the 450 but the mag body can be used, standard for the 458.

[Swamp Fox]

jonp- The 450 bushmaster is where I’m leaning too. It’s got good power, good availability, and it looks like it’s going to be the most common of the big bore ar cartridges. If it gets more popular, hopefully barrel prices will come down, which seems to be the hold up to cheap builds.

My reason for not really liking the 300 BO are mostly just arbitrary personal preference. I think it’s a good round, and I know a couple people who hunt with one with good results. But I’m just not impressed by the ballistics. It’s a step down from a 30-30 (which I love and hunt with), and power falls off pretty quick. I normally hunt hogs with a 45/70, and love the knock down power. It’s probably my single favorite rifle, so I guess that’s what I compare stuff too when I’m looking at other guns to hog hunt with. It’s got a lot to do with why I’m not real interested in the sub 30 caliber stuff, even though I know they are good, capable rounds.
It’s kind of funny, the last 20 years we have been hearing how we need magnum everything to hunt anything bigger than squirrel. All the gun writers and keyboard experts put down the 3030 as being barely enough, but all at once the new hero cartridge comes out and it’s got plenty of power. When was the last time one of them recommended shooting a deer at 200 yards with a 30-30?

[moorvogi]

I also went down this path! Over the last year, i built a 300blk and a 458 socom. Built loads for both and got to say.. i like the 458 more. HOWEVER consider the SAMMI info posted above. Assuming you're looking only ar15 not ar10.. my money is on 458 over 300blk.. can't speak to the others.

If ar10, 308 can't go wrong.

[Petander]

Hornady 350 FN @ 1900 fps, 75 meters, Tromix upper. Sorry for the j-bullet pic but my cast loads are not this accurate,not yet.

This is normal accuracy for this bullet,no lucky group.

232731

232732

[jonp]

Hornady 350 FN @ 1900 fps, 75 meters, Tromix upper. Sorry for the j-bullet pic but my cast loads are not this accurate,not yet.

This is normal accuracy for this bullet,no lucky group.

232731

232732

Nice group. You talked me into it. What bullet is that?

[244]

By the looks of it, I'd say that is a 405 grain Remington bullet.

I have and love my .458 SOCOM. I worked up a bunch of loads for my 16" barrel (sorry, all j-word bullets) a few years ago. After the initial brass and die purchase, reloads are cheap enough. Just remember to use Large Pistol MAGNUM primers (unless Starline has changed their brass to accomodate LRP's lately).

If you are recoil sensitive, the 6.8 would be a good choice too, followed by the .300 BO, then 6.5 Grendel/.264 LBC. You can use faster powders in the 6.8 and .300 BO to get the most out of 16" or less barrels, but as mentioned before, the 6.5 needs the barrel length to work its magic.

[Charlie U.]

I went with the 20" factory upper in 450BM and paired it up with my 24" Bushmaster varminter. Makes for an excellent deer rifle in the fall and then switches back to my varmint gun when the season is over. I have a Timney Targa 2 stage trigger in that lower so this combo is excellent for precise shots in either configuration.


https://i36.photobucket.com/albums/e3/gekkocha/20180527_184458_HDR.jpg

The 450BM is great for hunting hogs and deer. The 16" might be more to your liking, but I ran with the 20" purely out of personal preference. Both uppers wear Vortex scopes and I swapped out the factory flash hider for a Ross muzzle brake on the 450BM upper. Other than that one change they are straight factory uppers.

If I were to get one today it would be the Ruger MPR in 450BM. You can hardly build a better hunting AR for the price.

[popper]

458 Ham'r.

[Bigslug]

AR-15 - - WHY???

Based on your OP, a .45-70 Marlin would be a lot more straightforward and perfect for the job, with no need to wade through all the muck of figuring out what combinations of parts you need to make an autoloader run with a cartridge not even close to what it was designed for.

Buy Marlin, hang 1.5-5x scope, kill deer. Done.

[the_ursus]

Just started shooting a tromix 16” .458 and love it so far. This will be a hunting, target, bear defense etc rifle. I’ve primarily been working on cast rcbs 300 gr .458 flat point (335gr lubed and checked). It’s shooting about an inch at 50 yds with room for improvement I think. 39 gr R7 is as far as I’ve taken it and recoil at the bench is not overwhelming. Not sure of my cost per round but it’s very affordable with cast bullets so far. These big slow moving bullets are not likely to expand on game so I’m not expecting enormous wounds and penetration shouldn’t be a problem.

[Swamp Fox]

WHY NOT? Why do people climb mountains? Why go hunting at all? Wouldn’t it be easier to just go to the grocery store? I know it would be cheaper.
It you had bothered to read you’d know I have and love a 45/70 already. If not for curiosity and wondering “can I do this”, shooting and reloading wouldn’t be much of a hobby.

the ursus- what made you pick the 458 over 450 BM? Was it bullet weight/ availability?

[KCcactus]

I hunt with an AR in 6.8. 115gr Federal Fusion is impressive on both deer and feral hogs. The last Fusion I bought was on sale for $17/box with free shipping plus a $5/box rebate.

Recently picked up a Bear Creek 450 BM upper to play with. Managed to catch it in stock on sale at $208. They currently have 458 socom uppers for $240-250. I chose the 450 because my 45 cal molds are .452, I'm not interested in more than 300 gr boolits and factory ammo is less expensive. 250 gr at 2,000-2,200 fps is overkill for anything I'll find at my hunting spot, but it should be fun.

[Swamp Fox]

Those are pretty much my same reasons for leaning towards a 450 over 458. If I want to shoot a really heavy bullet real hard I can always get the 45/70 out. I’m still not fully decided, but if I had to order a barrel today that’s what I’d get. But I really love the idea of the 375 socom.
How about a review on the bear creek upper once you get it going? I’ve seen there stuff and wasn’t sure how good it would be. But you can get a whole upper for the price of a barrel anywhere else.

[BD]

I went through this decision process 10 years ago. I wound up building a 450B and never looked back. it's the 45 acp of ARs, lots of powders work, lots of bullets/boolits work, pressures are reasonable and brass lasts forever. Using the 250 grain FTX it can shoot exactly to the BDC reticules of both the Leupold and Nikon black powder scopes. Good for anything from 300 yards and under. I put it together and took it to the local, (at the time), range in NY with load work ups using the 250 grain FTX and 250 grain XTPs, Lil Gun and WC 297. I was shooting over the crony at 85 yards, (length of the range there), recording velocities. At the end of the morning I went down range and took down the target. All 80 rounds went into 1-1/4". I was sold. I'm about 2,000 rounds into it at this point, (mostly cast) and still smiling. I have a FTX target over my loading bench with a 1-1/2" group at 300 yards shot from a clean cold barrel my first day at the local range in SC off a rest. No sighters, just top of the post of the BDC reticule on the Leupold. About an inch to the right of the bull, but I'm not complaining. The only downside is that for best performance you really need to make a "neck crimp" die as the force of the bolt slamming home can override the Hornady taper crimp with heavy bullets, and if you use a roll crimp they don't always chamber consistently. The forum below is full of information. I was pretty active there when I was getting into this, not so much anymore. I use cut down .284 brass for bullets, (large primers, thicker neck, .452 bullets), and Hornady factory brass for bolts, (small primers, thinner case necks and small rifle primers). Lil Gun works great, but really heats up the barrel. H100 works, 296 works and I'm using WC 297, (just because I had 12 lbs on hand), and it works great too.

http://450bushmaster.net

[BD]

Another note: .450 B uses standard .223 AR mags with a "special" blue plastic follower, (my followers cost $3.95 back in 2009), or the Sig plastic 20 round mags right off the shelf, no mods needed. 20 round .223 mags hold 9 reliably. Biggest hassle is that if you're hunting with it you really should buy at least one 5 round Bushmaster mag that has ".450 B five round mag" printed right on the side or the local fish and game guy may try and take your mag apart to see if it's really limited to five rounds, (at least in Maine where I currently live).

[kbstenberg]

I am just starting to look into building a bigger better mousetrap. With both the 450 & 458 being shot out of an AR15. What has to be done to the BCG to handle the larger base?

[BD]

At least for the .450B, the bolt face is different, the rest of the carrier is the same.

[jmort]

After giving this more thought, and this thread was most useful, I am going with .458 SOCOM
Completely compatable with AR15

[Gtek]

For those diving into the SOCOM, please watch and inspect all when venturing into new loads. I will call it limited into this round and it went from nothing visible to trying to push the primer through the firing pin hole with just over a grain. This was especially evident when going with the heavies, start low, go slow and inspect each case until you have established, SOP you know the drill. There is growing load info online and I have enjoyed the ride so far. Another thing on the big holes, nobody dresses the extractor out. I am a LITTLE OCD and the extractors are always knives on outboard corners and eats ones brass really bad. Spend a little time and dress and roll corners, your brass will Thank You.

[lar45]

Just to muddy The waters a little...
Have you looked at the 358 Yeti?
https://www.maddogweapons.com/358-yeti.html
180 gn @ 2600 , brass is made from cut down 308 cases.

[DDriller]

For those diving into the SOCOM, please watch and inspect all when venturing into new loads. I will call it limited into this round and it went from nothing visible to trying to push the primer through the firing pin hole with just over a grain. This was especially evident when going with the heavies, start low, go slow and inspect each case until you have established, SOP you know the drill. There is growing load info online and I have enjoyed the ride so far. Another thing on the big holes, nobody dresses the extractor out. I am a LITTLE OCD and the extractors are always knives on outboard corners and eats ones brass really bad. Spend a little time and dress and roll corners, your brass will Thank You.
Tromix makes a very fine extractor just for the 458 Socom. He knows a little about them since he built the first one ever made. Also has proper bolts, not just some with the face milled.

[Gtek]

Mr. DD, thanks for the schooling! My post was simply information and called out no one. But since you appear to be a fan boy, one of the sharpest came from Tony's house a few years ago. Maybe slipped through the cracks, who knows. The brass is not cheap and most will reload, just trying to help. Just a thought, I have owned many firearms and I cannot think of one that a little polishing here and there did not help something.

[dkf]

Those are pretty much my same reasons for leaning towards a 450 over 458. If I want to shoot a really heavy bullet real hard I can always get the 45/70 out. I’m still not fully decided, but if I had to order a barrel today that’s what I’d get. But I really love the idea of the 375 socom.
How about a review on the bear creek upper once you get it going? I’ve seen there stuff and wasn’t sure how good it would be. But you can get a whole upper for the price of a barrel anywhere else.

The BCA .458socom parts have problems. The bolt isn't right (knife edge bolt which hangs up on the case, wrong ejector and extractor), the barrel has the lower lug on the barrel extension mostly cut away. I don't know how their .450bushy stuff is but their .458socom stuff is problematic and not done properly. In the last week or so there have been two guys in the .458 group with BCA .458 uppers with the same problems.

[jmort]

This is what is needed
https://tromix.com/product/complete-bolt-carrier-group-right-handed/

[Elkins45]

My next upper build will be a 458 SOCOM, and I’m getting the parts from Tromix. The difference in price between them and the guys using guesswork reamers isn’t worth the risk of getting a dud.

[sqlbullet]

I have AR-15's in four calibers: 223/556, 6.5 Grendel, 300 AAC Blackout and 458 SOCOM. I also have AR-10's in 260 Rem, 308 Win and 358 Win. If I had to pick one AR to be my hunting gun, it would be the 358 Win. I built it to be very lightweight, and it is. 358 Win is plenty of cartridge for about anything I you might hunt in North America.

But, you are looking at an AR-15.

I would take a 300 Blackout. Yes, the Hamr hits harder with bullets between 140-160 grains. But it catches back up pretty good on the 110 and 125 grain bullets, and it supports bullets way above 160 grain. And you don't have to shoot the heavies sub-sonic. You can get 1400-1500 fps in the 200-220 grain bullets, maybe a bit more out of a 16" barrel.

And yes the blackout lags behind the 30-30 in 24" barrels. But in 16" barrels I don't think the difference is that great. My google-foo found field reports of 16" 30-30 carbines chronographing 170 grain factory loads between 1900 and 2000 fps. The Blackout should be within 50 fps of that number.

But as long as you end up with a modern sporting rifle, you won't lose!

[KCcactus]

How about a review on the bear creek upper once you get it going? I’ve seen there stuff and wasn’t sure how good it would be. But you can get a whole upper for the price of a barrel anywhere else.

The reviews I've seen were mixed. At $208, I decided to take a chance. I've only tried it once so far. I loaded 11 rds with 200 gr plated target HP meant for 45 acp and 40 gr of IMR 4227 to test function and try to get the SPARC sighted in. The aluminum 223 mag I had didn't cooperate very well. Even after I removed the follower and carved it flat, it was a pain to load. If I put in three rounds, the mag swelled enough that it didn't want to go in the lower. It was still a tight fit with two rounds, but it worked. The 5 pairs plus the extra single fed, fired and ejected with no problems. I found a couple of small fragments on my backstop, so it appears the plated HP were coming apart on impact.

With a son in college, my toy budget is extremely limited at the moment. It will be a while before I can get a couple of steel 450 mags and some FTX to give it a fair test. Until then, I'll play with the .452 stuff I have.