Home Forums Hunting & Shooting AR and Tactical Rifles Are there any well functioning AR's in 350 Legend?

What is the formula to put together a reliable AR upper in 350 Legend? magazines? I haven't heard of anyone who wasn't having feeding problem. True or false?
Thanks for the input.-Mark & Belle

Brownells recommends using dedicated .350 mags with their Brn-180 .350, and have the CMMG mags displayed on the same page, which might be a hint. Trying to cobble up mags from .223s is just looking for trouble IMO.

Right now, Midway has a variety of uppers for sale, some discounted. The AR Stoner is clearly a re-branded Bear Creek. Bear Creek offers a good variety, including SS options, various barrel lengths, and both rear- and side-chargers, for really good prices, as usual. No experience with their .350s, but the two others I have are running very well, and are quite accurate.

Given my druthers, I’d like a BRN-180, but they’re much more expensive than other options. Even the CMMG and RR are less.

FWIW, all the DI uppers I’ve seen have carbine-length gas systems.

Just found this:

https://guntradition.com/best-barrel-length-for-350-legend/

It appears that barrel length doesn’t make a whole lot of difference in velocity with the .350, somgo with what you want to carry.

Thanks Pappy. I have two BCA uppers; a 6.5 Grendel and a 223 Wyld. Both seem fine and accurate, especially the Grendel which is 5/8-7/8" three round group at 100yd w/ my90gr Nosler Varmegedon loads. So, no problems w/ BCA in my small selection size. -Mark & Belle

I have two 350 Legend uppers and both feed perfectly. The first was a 16" Ballistic Advantage Hanson performance Carbine barrel, M16 bolt carrier, with Aero Prec XL upper and Duramags. The second was a 16" Pro 2A Tactical complete upper with Duramags. The key is wide ramps on the barrel extension and Duramags. Might have to adjust recoil spring rate and gas, but I have not. I really like the BA barrel with the "Big Bore" ramps in the barrel extension...seems to have the least resistance to the loaded cartridge moving up the ramp... So far, 7 hogs and one deer with the BA.

What's your definition of "feeding problems"? Feeding 1 cartridge? 3? 5? 20+?

If you want an AR that feeds well (i.e. an entire 30 round mag), you are barking up the wrong tree with the .350. It wasn't designed to be a great feeder, it was designed to give people in straight wall states an option and feed "good enough" for hunting.

350s are very ammo sensitive. If you can find an ammo that feeds 3 in a row you are GTG.

If you want something that feeds well enough for SHTF, look at a bottlenecked cartridge like the 5.56, something that has some body taper.

Hmmm….never even crossed my mind that sensible folks would look at it as a viable, magazine fed, defensive mainstay. A straight walled 35 is about as efficient as it gets if considering all factors in an eastern hunting cartridge.

I have an Echo 3 Ordinance rifle upper that I use on an Aero lower I built (with a matching blackout upper). I’ve used Duramags and the five-rounders that a e with my son’s RAR. No issues.

I use the same mags on a pistol variant (sorry, can’t remember which 12.5” upper I grabbed) with the same results.

George

My son bought a BCA upper last year and uses a CMMG mag and it feeds just fine. BCA recommends a couple of different mags.

From what I've read over the past few years is that people are having feeding issues when they use a hard cast bullet. Not sure if that's true or not.

Maybe a bit OCD?
I expect stuff to do what it's supposed to do.


A defensive gun to a slightly higher degree, but even the semi 22 pistols I use are
expected to run. When they don't, it's a problem needing fixed.

I built an upper using a Spikes slick side upper, Ballistic Advantage lightweight 16" barrel with a Toolcraft BCG and an Aero Atlas HG. It s been completely reliable with CMMG mags. It's my lower MI deer gun. Lightweight and accurate enough for what I'll use it for, reliably putting 3 into 1.5" before barrel heat becomes an issue.

Old70.

Not a 350 legend guy, but magazines are paramount for reliability. Use the recommended mags for that round. My Duramag 7.62x39 AR mags are the magic for my M4 builds.

The secret is the bullet, and polished feed ramps. I found that spitzer and semi-spitzer bullets feed reliably in my build.
Pistol bullets are problematic because of the short length and blunt nose. They jam into the feed ramp before they can enter
the chamber.

I have found for my use that a speer hot core 180 gr. resized to ".356 feeds all the time, and is a good bullet for game up to
deer. The magazines I use are from Wilson Combat and the Pro-mag, both supposedly designed for the 350.

I have a BCA upper, which was cheap, and is reasonably accurate. It won't function at all with 5.56 mags, but works fine with appropriate mags. I've mostly loaded the 170gr Hornady, and they shoot well, and kill pigs well.

Originally I thought the Legend might be a great all-around cartridge for the AR, but the need for special magazines is a drag.

I have a 16" 350 legend upper from Midway, on sale. with a Palmetto undercarriage, also a blue light special. Had a coveted, in my corral, Aimpoint on it. Aimpoint has gone to my new favorite,so now the second place 350 legend has a Sig Romeo and Juliet combo. The upper has been great with all Winchester white box and hunting but mostly suppressed 255s. Could not get any Hornaday rounds to function, single shot only with the horaday black box or hunting or quiet stuff. Always ran with Legend magazines from Midway a big and a small. Carbon buildup comes on quick with a can on. Most of the empties are soot covered. Havent really wrung it out for accuracy, sighted in and called it good. The orange follower in the mags gets full of soot. Knocks the plates off the Texas star with authority.

Maybe re-read my post. I’m not saying it shouldn’t run reliably. I’m saying I don’t know why it’s a primary defensive choice. I can defend with my Kimber Montana….if I have to. It’s not what I’d choose first.

Was speaking for myself, agreeing with you.



Even on a “meat gun” I wouldn’t be happy with malfunctions. No a personal issue, we can’t be trusted with semiautomatic deer rifles.

I dunno. Assuming a reliable rifle, it oughta be pretty dang effective. Might “over-penetrate” a bit for apartment use😱 Hornady has a SS load.

There are many places in the east where shots may be presented at distances where most of us would prefer something with long range potential that considerably exceeds that of a straight wall .35 popping short fat bullets out at unimpressive speeds, just as there are many places in the west where one would be well served with a .35 Remington or a .30-30.