Which ar upper build next? Not 5.56

[pretzelxx]

I'm looking for a good, FUN, round to cast and load. I'm not TOO concerned about brass availability such as the 458. I'll go slow with it. I just want an adventure. I'll be taking my time to acquire higher quality stuff. I'm looking for opinions on the most fun round to load for an AR. Thanks to all who provide input!

[nhrifle]

Take a look at the 300 AAC. Brass is easy to make, shoots cast very well, quite accurate, low powder consumption and addictively fun.

[freebullet]

I vote 45-70

[pretzelxx]

If I could, I probably would with a 45-70. I'm looking at the brass for 300, interesting stuff. Didn't know you could trim it down!

[Jailer]

My 300 blk has been getting all my attention for while now. It's easy to cast for and fun to shoot.

[garym1a2]

9mm or 45acp with a lower that takes glock mags.

[frankenfab]

I vote 300 BLK

50 Beowulf--you aren't going to be able to build it because of parts availability, but you can buy an upper at Midway right now.

458 SOCOM---same as above, but you cant buy an upper right now either

450 Bushmaster---I have yet to see a report of success with cast in this caliber for some reason, so I have crossed it off my list for now.

[pretzelxx]

I am not a fan of glock, but I DID think about pistol caliber. I think the 300 will be a very very fun round to work with, and I may go for a suppressor! It'll be a while tho before I get a can.

[frankenfab]

BTW, if anybody HAS had success with a 450 BM, please do tell. AR's are like ice cream to me. I like several different flavors.

[rodok]

The 300 Blackout is fun to shoot, and 556 brass is so plentiful and mine shoots cast just fine, with a 16 or 17 grain load of powder you save money that way too.

[pretzelxx]

Im currently looking at barrels for a 300 blackout. Thanks everyone! That was easy convincing!!

[Houndog]

I guess I've got to be different! I'm currently working on a 6x45. I'm useing a Douglas double button rifled 1/12 twist barrel I'm recontouring for a 20" upper with a gas piston system and floating forend.

[garym1a2]

300 blackout can be a bit of work. Buy a good case trimmer to start with.
Im currently looking at barrels for a 300 blackout. Thanks everyone! That was easy convincing!!

[xacex]

This crowd like the 300 blackout if you can't tell already. I agree, and own 3 of them myself. The other fun ones are 50 Beowulf, and 6.5 Grendel. The grendel only has one boolit that has been reported to to do well and it is the seico 140 grain.Converting and fireforming 7.62x39 brass is not hard to do if you cannot find 6.5 brass for some reason. I do not have the mold myself, and do not have any load data to share on that one. Those are the three calibers I will keep around besides the 5.56...

[supersniper]

+1 for 300 Blackout

shooting cast subs for 6 cents each and supers for 9 - 12 cents each depending in gas check or not.

[wlc]

I'm not a huge AR fan at all. I do have a couple....well...just because.. That said, My upper in 300blk is getting the most trigger time right now. Fun to play with, easyish to load for, cheap to load for and quiet. I only load subs for mine so casting is a no brainer. Heavy jacketed rounds are +-.35 each just for the bullets. With cast I'm looking at less than .10 per round. Nice thing is if you don't want to put a whole nuther upper together you can just change the barrel on an existing upper.

[pretzelxx]

I did think about just a different barrel, but I figure an extra $100 or so isn't bad for a flat top upper. Problem is finding a pistol gas ported barrel with an adjustable block.

[freebullet]

You would get major props if you pulled off the 45-70 build. I wonder what kind of angle the rounds would sit at to even get them in an ar mag. You would need something from the bolt to trip and release/eject upward one round prior to the bolt coming forward.

Joking aside a 9mm or 45acp would really be a hoot to shoot. Otherwise the 450 or 458 would be quite impressive dependant on which had better ballistics options.

I don't have anything against the blackout but if you have 223 & 7.62x39 already I wouldn't see the need. New builds aren't always about need though. I don't think any caliber would be a real bad choice

[Artful]

If I could, I probably would with a 45-70.

Start with this firearm AT 14 .410 shotgun
http://www.thefirearmblog.com/blog/2009/01/26/at-14-the-410-ar-15-shotgun/
then convert to 45-70 - should be a cake walk.

[Artful]

BTW, if anybody HAS had success with a 450 BM, please do tell. AR's are like ice cream to me. I like several different flavors.
some links for ya
http://castboolits.gunloads.com/showthread.php?38506-Anyone-else-loading-for-a-450-Bushmaster
http://castboolits.gunloads.com/showthread.php?216288-450-bushmaster
http://castboolits.gunloads.com/showthread.php?165209-450-Bushmaster
http://castboolits.gunloads.com/showthread.php?138448-PP-450-Bushmaster
http://castboolits.gunloads.com/showthread.php?40037-450-Bushmaster-tell-me-about-it
http://450bushmaster.net/viewtopic.php?f=5&t=5252&start=10

[jackmanuk]

How about 45 acp and make a super silent AR

[pretzelxx]

Interesting 410 link, thank you. I might keep my options open, I'll ask the wife her opinion! And the 450bm links as well thanks.

[Jupiter7]

Another 300blk vote(I have 3, 10" AR pistol, 16" carbine & rem 700) for ease of use and availability of components. It's very efficient and will run the gambit of 30 cal weights. Personally though for FUN, ease of loading en masse has it's own merits. Rifle brass prep still irks me. Loading straight wall pistol cartridges is just easier and cheaper, my second suggestion is a pistol caliber 9mm, 40, 45, 10... There are a couple guys making DI 45auto upper( most are blowback) that's run on modified grease gun mags. The action is strong enough that you could load 45+p or 45 super. 9mm is most common for blowback and most likely easier to build from home.

[prsman23]

I'll chime in with another blackout vote. It's been a good time. Making the brass is tedious. But if you do a little at a time not too bad.
I'd suggest putting some new brass in the build budget if you don't have a bunch of spare time.
The round itself rocks, no need to explain more.
I'd suggest doing an sbr for an extra bit of uniqueness at the range. Plus it's nice that the round doesn't lose much in a short barrel.

[M-Tecs]

The ones I will be doing in the near future are a 204 Ruger for prairie dogs and yotes and a 458 SOCOM just because I want one. I would also like a 30 Rem AR for deer but Remington sc###d the pooch so badly on this one I'm not sure it's a viable option.

[pretzelxx]

I only have one lower, not too interested in making two whole ARs. Could I still use the sbr engraved lower with my 18in 5.56 upper? I'm not sure how that works.. if the answer is yes, I might actually go ahead and fill a form 1. Just a little more time to save for the tax stamp.

[prsman23]

If you change uppers you can use the same lower even if it's engraved for sbr.
The sbr rules don't apply if the upper barrel isn't under 16"

[pretzelxx]

Sweet!! I just found a quick search with a lot more details, great suggestion! I didn't know ideas that easy. Now to set up a trust.....

[Artful]

If you file under a trust use the E-file system - currently it running much quicker than the paper copy processing.

[pretzelxx]

I plan on lurking at that ar 15 forum... I'm scared to register there, they seem like such fan boys. Not that's bad or anything, but they might lure me in. I believe I saw a post in how to fill out the form and how to have your own "trust" with an e-file system. And besides, I have pretty bad handwriting I would probably get denied haha.

[pretzelxx]

So I looked for the 2 inch cut off saws I see everyone on YouTube using, and harbor freight seems to have discontinued the little things. Seems now I'll have a lot more work to chop down my 5.56 brass.

[wb2754]

I'm doing a 6.8 SPC build.
It seems to be a quite capable cartridge from what I have read. Supposed to have good accuracy out to 500 yds or so with much better terminal performance than .223, but still using the AR15 platform.
Not much available for molds in this size though. I started a thread in the group buy forum seeking interest(or not) in this caliber.

[freebullet]

How about a 380acp? Never seen one of them, lol. Would actually be quite fun, silent, and conversational in a pistol configuration.

[Moonie]

I'm doing a 6.8 SPC build.
It seems to be a quite capable cartridge from what I have read. Supposed to have good accuracy out to 500 yds or so with much better terminal performance than .223, but still using the AR15 platform.
Not much available for molds in this size though. I started a thread in the group buy forum seeking interest(or not) in this caliber.

I have an upper in this caliber, I also have an old Ideal mold for it that works well. There have been a couple of discussions about a mold for this caliber and at least one group buy that actually went to completion. A Mihec mold if I remember correctly.

My 6.8 SPC rarely gets used since I built a 300AAC BO however.

[DeanWinchester]

For the ultimate thumper, there's a guy out there somewhere [can't recall right now] building AR-10's in .450 Marlin.

[nitrohuck]

The 300Blackout cartridge is a cast shooter's dream cartridge.

I went with it for my first and currently only AR build in my collection. I was upset to learn that 5.56 is relatively finicky as far as cast boolits are concerned in the AR platform, and when I began learning about the 300BLK I am pretty sure I heard angels singing in the background.

I shoot the NOE 314-129 boolit supersonic out of my 16" carbine gas AR and just using Xlox lube and WW alloy I can push it to 2,200fps with zero leading.

So in short: 300BLK 300BLK 300BLK 300BLK 300BLK 300BLK 300BLK

[wch]

I vote for the 6.5 Grendel.

[kawasakifreak77]

Blackout!

Mine is a semi custom bolt gun (ARs just don't excite me) but regardless this caliber is like crack!

[pretzelxx]

I do want a bolt gun, eventually. I was thinking a tad bit bigger and longer range.

[Artful]

So I looked for the 2 inch cut off saws I see everyone on YouTube using, and harbor freight seems to have discontinued the little things. Seems now I'll have a lot more work to chop down my 5.56 brass.

Think bigger :bigsmyl2:
http://www.harborfreight.com/6-in-cut-off-saw-61204.html#.Uy40AKhdVuI
http://www.harborfreight.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/i/m/image_22778.jpg

or you can use a bandsaw
http://www.youtube.com/watch?v=jXQjPy7Uvdk
or drill or drill press
http://www.youtube.com/watch?v=2x93hAJiD3o

http://www.youtube.com/watch?v=KcYNARehSeE

Giraud Case Trimmer
http://www.youtube.com/watch?v=UoFH6Ho4FA8

or if you have the bucks
- Dillon 1200b - even better in 1050 press as it removed primer crimp at same time
I actually quit making my own and just pay my friend to do it for me.

http://www.youtube.com/watch?v=c1FIs0FDmFQ
Dillon case trimmer

[pretzelxx]

All good ideas, thank you!

[BD]

I've been playing with a .450B for a few years now. How do you define success? My rifle will shoot any of 10 designs, over three or four different powders into 2 1/2" @ 100 yards all day, every day. My problem is that many of those five shot groups have three in less than an inch. If I could just eliminate the flyers, I'd find happiness. My rifle will easily keep 250 FTXs under 1 moa out to 300 yards. And i have sat down at the bench and put 50 rounds of condoms into an inch @ 100 more than once. I just know I could do the same with cast if I could just cure those pesky flyers. I rarely see .458 Socom, or 50 Beowulf groups posted, so I can't say how the .450B stacks up against them with cast. However, I do like the 24 twist, availability of brass, brass life, many suitable boolit designs the variety of usable powders, and the availability of BDC scopes matched to the jacketed ballistics.

The .450B in an AR is the .45acp 1911 of the rifle world.

BD

[pretzelxx]

Now that is some strong reasoning why I should do that. Thank you.

[Artful]

I rarely see .458 Socom, or 50 Beowulf groups posted, so I can't say how the .450B stacks up against them with cast.
BD

http://i695.photobucket.com/albums/vv314/1911canebrake/ammo/DSCF1512-1.jpg
http://teppojutsu.com/458FAQ.htm#_What_type_of_accuracy_can_I_expect_

As with velocity, accuracy will vary from rifle to rifle. The cartridge, however, is capable of quite respectable accuracy. With hand loads, low power optics and the shooter doing his job, groups as low as 0.5" (yes, true 0.5") have been recorded. We typically tell folks that 1.0" groups at 100 yards are the norm for the 300-grain JHP load. The 500-grain subsonic load does not appear to be as accurate but it was never meant for ranges beyond maybe 50 yards.

http://www.policemag.com/channel/weapons/articles/2008/10/rock-river-arms-lar-458-carbine.aspx


I was impressed with the accuracy that I obtained with the LAR-458. I am certain if I had more time and more rounds to experiment with that I would have shot some even tighter groups. Still, how can you complain when the carbine is producing groups under an inch at 50 yards? Several of my groups were big ragged holes rather than five individual holes.

http://www.ar15.com/archive/topic.html?b=3&f=121&t=502821


My .458s will hold MOA at 100 yards, but at 200 things start to open up to about 1.5 to 2.0 MOA. I have not tried farther since the drop of the bullet at that range makes range estimation critical if you are going to hit where you want, and wind really starts to blow that sucker around when the velocity starts dropping so low. And as you start to cross the subsonic barrier which happens at around 1125 fps, bullet stability is affected and that can blow a good group also, and if your bullet starts at 1800 fps, it goes subsonic right before it reaches 300 yards.
I have found H110 to be just about the ideal powder for the .458 SOCOM in barrels from 12.5 to 16 inch and with CAR or Middy gas ports and bullets to 405 gr.
Frankly, to be honest, trying 300 yard plus shooting with the .458S IMO is equivalent to jousting windmills. It may be done, and it can be fun, but it serves no real purpose. For long range shooting there are better rounds and for God's sake, don't use them on game animals. They will not expand and at that slow a velocity they do not pack much energy either, only 876 ft-lbs is left of the initial 2338 it started with.
...


I am pretty sure it was Marty that fitted up an AR with a folding long range Creedmore type peep sight. It can be done for kicks and giggles, but it is not going to be easy and small groups are not going to be common. My point was not to get your hopes up of great success shooting the .458 SOCOM at long range and getting 'small' groups. Shooting 18 to 36 inch gongs is one thing, shooting groups that most would consider 'small' is quite another (remember, a 36 inch gong at 700 yards is over 5 MOA, and even an 18 inch gong is 3 MOA at 600 yards and that is not exactly what the OP was looking for since he was disappointed in the groups he was getting at 300 which were nowhere near 5 MOA.
The good news is the .458 SOCOM is perfectly capable of taking those 500 gr. bullets of similar weight as used in the old buffalo rifles and launching them at near the same velocity black powder gives in the .45-70 out of a stronger than Trapdoor rifle, such as the Sharps. Expect about 1200-1300 fps and you can ring that gong all day long, but small groups, by my definition of small which is MOA or less, not going to happen.
...
http://img.photobucket.com/albums/v617/martytw/458SOCOM720yardsightpicture.jpg
http://img.photobucket.com/albums/v617/martytw/458SOCOMELRPeepSightview.jpg


While the .458 was indeed intended for "up close and personal" engagements, several folks have surprised us with longer range results. Those longer range results have been divided into two categories: volley type "pocket artillery" on larger targets (e.g. 2'x2' gong at 700+ yards, mimicking a hit on a parked vehicle to render it inoperable) or up to 400 yards with higher pressure loads in bolt action rifles. Originally we had anecdotal results from the bolt action guns (Win M70 integrally suppressed delivering head shots at 400 yards), but recently we received some newer results showing 3.75" (C-t-C) at 300 yards with the Barnes TTSX.

So while it can be done, it will not be small groups as seen with more dedicated long range rounds like the various 6.5mm, 7mm, .308 cal and .338 cal out there.

[Artful]

50 Beowulf
http://castboolits.gunloads.com/imagehosting/thum_89094eed574690075.jpg
photo credit to 101airborne
Alexander Arms claims it'll do 1 MOA.
http://www.alexanderarms.com/products/50-beowulf


http://i27.photobucket.com/albums/c166/dakang3/kiddos/2012-09-05_09-44-14_784.jpg
http://www.texashuntingforum.com/forum/ubbthreads.php/topics/3578613/50_Beowulf_accuracy_question


yea I wouldn't call a fist sized group that great, pretty blunt I know. When I used to use factory ammo I could still get pretty decent groups within about 2" or so in a 5 shot group. They got a lot closer with reloads/me shooting the beowulf a lot more and not flinching so much. I had maybe 1 flyer out of the group of 5 with the factory ammo, very well could've been me flinching/pulling the trigger and gun trying to brace for the kick. Now with my reloads I still get a flyer due to me either being over confident, rushing my shot, or still pulling the trigger/flinching.

this next picture is from a few months ago at 100 meters. I let a few people shoot it to see what it was like at the range. very top two are one person's two shots, bottom 5 shots towards the bottom and right are another guy's 5 shots. the one shot a half mile below the 9 on the left and the 3 next to it are me just shooting it real quick. last 5 in the center are my last 5 shots actually paying attention to what I'm doing.
http://i27.photobucket.com/albums/c166/dakang3/kiddos/2012-06-16_12-02-47_259.jpg


http://www.gunblast.com/50Beowulf.htm
http://www.gunblast.com/images/50Beowulf/Mvc-004f-sm.jpg

A good deal of the enthusiastic response to the .50 Beowulf resulted from the excellent inherent accuracy of the gun / cartridge combination. This 3/4" 100-yard group is a testament to both the design of the cartridge and the quality of the rifle.

http://www.thetruthaboutguns.com/2013/12/ralph/gun-review-beowulf/
http://truthaboutguns-zippykid.netdna-ssl.com/wp-content/uploads/2013/12/DSC00364.jpg

All our shooting was from 100 yards. We didn’t fling a ton of lead downrange, so I can’t represent our testing as a full 500 round shoulder crushing shoot ‘em up. As far as optics are concerned, we used a 1x Eotech red dot sight as opposed to a good 3x or 4x scope. Magnification would have aided our shooting; well, it certainly would have aided mine. However, even without a long period of familiarity and appropriate magnification, I’m reasonably certain that the Beowulf carbine would manage 2 MOA all day long.

For its intended uses, that’s plenty accurate enough. The .50 Beowulf was not intended to be a precision target round any more than was the .45 Gov’t. It’s more of a blunt instrument, and should kill anything it hits.

http://www.beyond556.com/bboard/forum/ammunition/handloading-reloading/big-bore-loading-data-only

[Artful]

Something else to keep in mind is component availability.
450 Bushmaster .451/.452 molds required
458 SOCOM .458 molds required
50 Beowulf .499-.502 molds required

[pretzelxx]

I think that's why I haven't done the 458 or 50. However, I want the 458 someday, regardless of availability.

[BD]

Thanks Artful, those groups are another advertisement for the .450B. Seems it will run with the two bigger boys using cast, while they're running condoms.
BD

[dkf]

Going to build a .458 socom next when I get the extra cash.

[rockrat]

Group size with all three have been similar. 1.5" or so @100yds. If I could get a bit longer barrel for the 450b I would like it alot better. It still shoots very well with just about anything I have shot thru it.



Artful---where did you get that sight?

[Artful]

Artful---where did you get that sight?

The pictured sight was from Marty at Teppo Jutsu the developer of 458 SOCOM cartridge - follow the link I put up by the picture...

That was an ARMS #19 mount with a custom block and then a Wesson & Harrington Long Range sight by Smith (Brownells listing for sight).
http://www.brownells.com/rifle-parts/sights/rear-sights/wesson-harrington-long-range-sight-prod18735.aspx

[johnly]

My 458 SOCOM shoots exceptionally well, but if I were to suggest an AR upper for cast bullet shooting it would be a 7.62x39mm.
Easy to find ammo, brass and components; more case capacity than a 300 BLK should you need some extra performance. My Colt 7.62x39 will easily place 5 rounds using a 311410 pushed by 13 gr. of 2400 into 1.5 inches using a cheap red dot holographic sight.

John

[DanWalker]

I have a 45 ACP upper from RMW extreme that is a lot of fun to shoot. I am waiting on a magwell block to allow me to use H&k Usc mags in it. I'm currently using standard Pmags and only loading one in the chamber and 2 in the mag. I also have a 300 BO upper and it is a blast as well. I feed mine 150 grain boolits cast from a Mihec GB mold. Had to modify my feed ramps to get it to feed those flat nosed boolits, but it shoots them great. Still breaking in both uppers. Been busy with domestic chores and work, so they will get a more thorough wringing out later this spring.

[MrWolf]

Just saw this thread. I have two lonely lowers and two kids in college so for now just dreaming but my next two builds would be the RRA 458 SOCOM Beast (NJ need muzzle brake) and the 6.5 Grendel. I have a Marlin 45-70 and like the idea of something like it in an AR platform.

[pull the trigger]

I just was going thru this same dilema. The answer I came up with is the 7.62x39.

[pretzelxx]

I also thought about the x39, but I'm not a huge fan of the extreme tilt the mags have. I am a major fan of the boolit choice availability in 300 and x39, so it's a tough decision.

[Artful]

If I had to have a 7.62x39 AR - I'd shop for a AR47 lower so it could run AK mag's.
But keep in mind a lot of bolt failures in the AR's in 7.62x39 so buy only the best parts

[xacex]

Ah, I got the itch for another build this week. Ordered parts for a dedicated 9mm pistol build with a Green mountain 10.5" barrel. Fun stuff! Played with the blackouts this week with my son. Both of us had a blast, and by the end of the day he was done with 5.56. Said I could sell em off and he wouldn't care. The Beo stayed home for this outing. Some days I just don't feel like shooting a hundred rounds till I'm sore in the shoulder.

[Jupiter7]

I have a 45 ACP upper from RMW extreme that is a lot of fun to shoot. I am waiting on a magwell block to allow me to use H&k Usc mags in it. I'm currently using standard Pmags and only loading one in the chamber and 2 in the mag. I also have a 300 BO upper and it is a blast as well. I feed mine 150 grain boolits cast from a Mihec GB mold. Had to modify my feed ramps to get it to feed those flat nosed boolits, but it shoots them great. Still
breaking in both uppers. Been busy with domestic chores and work, so they will get a more thorough wringing out later this spring.

How is the quality of DI upper? I've been considering one. Have you looked at the Olympic arms mags? They don't require a magazine block, not sure if they work with the rmw upper.

[DanWalker]

Upper is GREAT. Quality stuff. I think Olympic requires their lower to be used. I am running my upper on a bushmaster lower. RMW sells a magwell block and modified grease gun mags for his. I'm just cheap and in no hurry. I will wait for the block to use USC mags. I can get them from promag for a LOT less than the modded GG mags. I had a 7.62x39 upper and sold it. I worked and worked with it, doing all sorts of mods to mags and feed ramps. Never could get 100 percent reliable feeding from it with anything other than FMJ's. My blackout just required some feedramp opening and it now feeds anything I want to load, slick as snot.