Thinking About A .30 Or Bigger AR Where To Start?

[DougGuy]

I don't have an AR and never have owned one, I never liked the 5.56 or the 7.62x39 but I would like to have one in .308 (or equal in energy), .35, .40 or even .45 caliber. What is practical, easily doable, reliable, halfway affordable, and where to start with one?

I figure this late in the AR game, most of the flash in the pan wildcats have come and gone, the fads and craze curve is settled down to some known good things that work and are well accepted.

Thoughts?

[dragon813gt]

Do you want an AR15 or AR10? You need to start there. W/ the AR15 you have 300 Blackout and 458 SoCom along w/ a host of other cartridges. W/ an AR10 you have 308 and other large rifle rounds. I know someone makes a 358 Winchester upper. Decide which platform you want and then decide on the cartridge.

[C. Latch]

I had a 9mm once and regret selling it. It's easy to make an AR10 in .358 winchester, if that's what you have in mind, but if you want to stick with the shorter AR15 platform your options are more limited.

I've toyed with the idea of this:

http://www.tromix.com/375-socom-parts.html

[Mica_Hiebert]

I hardly consider 308 affordable to shoot in a semi auto :-D but I dont consider $.24 a round for 5.56 at half the cost of 308 "affordable" either im still stuck in my 9 cent a round delusions i guess.

[dragon813gt]

I figure this late in the AR game, most of the flash in the pan wildcats have come and gone, the fads and craze curve is settled down to some known good things that work and are well accepted.

Thoughts?

I missed this the first time. Not even close when it comes to wildcats. There always seems to be a new cartridge available. But a lot of them are just slightly tweaked from previous ones. There are a lot of choices and you're going down a rabbit hole that is very deep.

[DougGuy]

Maybe a 300 blk would be the ticket.

[dragon813gt]

Maybe a 300 blk would be the ticket.

One of the cheaper routes but still not cheap. The barrels are more expensive than 5.56 by a good margin. And you have potential cycling issues between subs and supers. Pistol length gas system takes care of a lot of this.

If you want the most powerful for the AR15 platform then look at 458 SoCom and 50 Beowulf. I will warn you about brass prices up front. Neither is going to be a cheap option. But they offer a lot of power in a small package and are fun to shoot.

[DougGuy]

I looked at those too, and at the 450 bushmaster as well. There is also a 375 Socom that has a lot of what I think I might like too. The 458 is way more boolit and energy than I would want although stopping car engines would be fun..

What would you have if you took the 300 case and took the neck out of it to make it more or less a straight walled cartridge?

[Ford SD]

I looked at those too, and at the 450 bushmaster as well. There is also a 375 Socom that has a lot of what I think I might like too. The 458 is way more boolit and energy than I would want although stopping car engines would be fun..

What would you have if you took the 300 case and took the neck out of it to make it more or less a straight walled cartridge?

The 300 aac blackout Headspaces on the shoulder -- if you made a wildcat you will spend lots of $$ for barrel/ dies etc

300 blackout works with only 5-6 powders But can be a lot of fun
you can make brass from 223
and you can make app twice the # of rounds per lb 300aac vers 308w

So Primers sr/ lr are about the same price per round
j Bullet or Boolits are the same price per round
Powder 10-20g per ver 16-50g for the 308 (est only-- your results may vary)per round

Ar15 Parts every where
300aac blackout Barrel you will have to shop around

AR10 Some parts will only work with the Parent Company So I have heard

[Mica_Hiebert]

but if x39 doesnt impress you neither will 300 blk

[Happyguy]

I shoot AR15s in 5.56, 6.5 Grendel, 6.8 SPC, 300 Blackout and 50 Beowulf. They are all fun and each has it own different niche. I also shoot a 308 on a DMPS platform. I had one in 10mm and regret selling it. Maybe that will be my next build.

[dragon813gt]

There is also a 375 Socom that has a lot of what I think I might like too.

Two words, brass availability. If you can't make it from LC brass or Starline doesn't sell it then I don't want it. Being able to buy brass from only one source is setting yourself up for shortages. Just something to think about.

[Moonie]

We have 5 uppers in the family, 2 300BO's, 1 5.56, 1 6.8 and 1 6.5. Honestly the 2 300's get the most use because they are just fun to shoot. For hunting or long range the 6.x's get the nod. The 5.56 rarely gets uses, in fact I think my son sold it to his step-father because it hadn't been shot in a couple of years.

[Vann]

I've had an Armalite AR10 for about 10 years now and have built several AR15 rifles. The first thing that comes to mind about the AR10 is its big and heavy. The 50. Beowulf reminds me of shooting a 20ga slug gun, nothing rapid fire about it. My next build is going to be a 25/45 Sharps I think that it'll do everything I need.

[S. Galbraith]

.308s are great for sitting/laying in a position and shooting stuff from a rest. They get cumbersome when you try to use them like an assault rifle in that ever part on the rifle must be beefed up to handle the recoil. Another downside, is that most .308 ARs are hard on brass, making them less reloadable.

The 5.56 sized AR can do a lot of things, depending on what you want. The most versatile caliber would be the 6.5 Grendel which has stellar long ranged performance and will take medium sized game effectively. The 5.56 is getting better and better as technology advances though. I don't see the 5.56 leaving LE and military service any time soon with these advances. .300BLK?......basically just a weaker 7.62x39. I would only consider .300BLK for suppressed use or barrels under 10". There are other calibers like 6.8 SPC, but personally I think the caliber is probably near death. For me, the only reason to venture beyond 5.56 is for improved across the board effects.......which at this time would probably be 6.5 Grendel.

[Jupiter7]

I have 300blk, 7.62x39 & 50beowulf.

300blk- easy to do subs if necessary, easily made brass, about 200fps slower than 7.62x39 with 125grs bullets, lots of bullet options and easy to cast for, was my first rifle casting adventure, still shoot it more than any of the others, this I would recommend but be prepared, some have issues getting cycling and feeding right. Also, enabler of SBR's and supressors :)

7.62x39- I built this for one reason-cheap steel cased ammo- don't reload for it- cases aren't easily accessible or cheap(most the time). I do have dies and brass, just in case. Carries issues with bolt thrust and requires special care and parts, not recommended as 1st AR

50Beowulf- this was built as a just because, didn't have any .50 anything, easy to cast for, cases are not cheap but last a good many loadings, straightwalled so kinda like loading pistol, recoil similar to 12ga, lots of power at short range, wouldn't recommend as 1st AR

My next and second recommendation would be 6.8SPC. Yes requires special parts but really is the gateway between the AR15(5.56) and AR308(7.62x51). Backed by major manufacturers, most factory loads available other than above military calibers. Proven reliable and enough oomph to take deer out to 400yds. Not sure if cast is a necessity and not really a great selection of .277 molds out there.

Then there is the easy path- step up in platform to the ar10/ar308, easy ammo, easy cases, easily loading, cast friendly within reason. I skipped the .308 for the .260rem in mine to get further range. But still applies, make all my brass outta LC brass. 358winchester an option here too.

too many options!!!! As always, most will say, get a regular .223/5.56, I tend to agree.