While shooting one of my .308 ARs about a month ago I got the completely impractical itch for a .50 BMG rifle. I had shot one a few years ago (a Barrett M82 which ended up being my baseline for comparison) and I think it took about a year for the stupid grin to come off my face when I thought about it. Watching Jerry Miculek's Youtube videos rapid-firing a Barrett and various other shenanigans certainly didn't help my self-control, so I started looking at options ranging from basic tube uppers up to a Barrett M82. I prefer a semi-auto style but was open to a bolt-action, although I don't like bullpup designs (especially for a .50 where that round is any closer to my face than necessary). I ran across some 2009-2012 timeframe forum posts about the Bushmaster BA50 and found a couple extremely short Youtube videos about it; there's not a whole lot of information out there on the rifle (Bushmaster purchased it from Cobb at some point around 2008) but what I did find seemed to hit almost every checkbox on my shopping list plus a few bonus extras that I hadn't considered:

- It's magazine-fed (10 rounds, comes with 2 mags).
- It's a bolt-action, which wasn't my first choice but the bolt is on the left side and ejects to the right so the shooter doesn't have to use their trigger hand to fiddle with the bolt.
- It comes with a removable bipod, although I ended up not liking the loose fit that allows movement for uneven surfaces because it freely flops around - I'm going to DIY some sort of front rail or other attachment point to see if an Atlas bipod might work better.
- The stock is pretty nice with adjustable length of pull and cheek rest height (Magpul PRS). There doesn't seem to be any need for a rifle-length stock, since the buffer tube is empty, but it works for now.
- It's pretty accurate with a free-floated 30" Lothar Walther match grade barrel; there's a smaller size 20ish inch "carbine" barrel version available as well which shaves off a couple pounds of weight but I stuck with the 30" model because I was worried about unburned powder and loss of velocity / accuracy. Accuracy was the biggest detractor I've seen for the Barrett rifles (mostly the M82 which was my original focus). Everything I found claims 1moa with M33 ball ammo and potentially better with something like the Hornady A-MAX).
- It comes with a very nice (although heavy) pelican-style case with wheels on one side.
- I didn't realize it at the time of purchase but Bushmaster did away with the huge blocky muzzle brake shown in most of the stock photos online, they now come with an AAC brake to mount their Cyclops suppressor, which will save some $ later on if I form1 a new can or buy a Cyclops for it.
- It's basically a massively oversized AR15, with identical controls for safety / mag release and as far as I can tell from first inspection it uses a semi-standard trigger group (the hammer is different). I thought at first to replace with a Geissele trigger / hammer but the stock trigger isn't too bad at all (about equivalent to an ALG adjusted mil-spec trigger).
- The cost was well under the MSRP (got it ordered through a local shop for $4100 plus state tax). I didn't have a firm budget in mind when starting the search, but that price point allowed me to get the rifle plus a great scope (Nightforce NXS 5.5-22x56), some ammo, and a few other extras for what I would have spent for the Barrett M82 (rifle only, no optics) which I apparently wouldn't have been able to attach a silencer to down the road.


All-in-all it's a heavy bastard (30 lbs empty), which is the same weight as my primary point of comparison (M82). I took off the fore-end rail because I don't think it'll serve any purpose for me and I could shave off a bit of weight. The videos I saw of people shoulder firing the thing must have some long damn arms; I'm not too tiny (6') but the Magpul PRS stock is too long for me to pick up and shoulder the rifle. I might replace it with something collapsible down the road and fabricate a new handguard that's a bit lighter to shave off a bit more weight. I don't have any delusions of packing this thing into the woods to go hunting whitetail deer, but I'll gladly trade a bit more felt recoil for a couple lbs less heft so it doesn't have to be shot from a bench or prone. In the end I'm very happy with the purchase, and can't wait to shoot the thing! There's only two ranges in close proximity to me that allow .50BMG rifles, and that's only one day per month each at 600 yards, but I don't get out all that often to shoot between work and family so it'll be more of a range toy to periodically refresh the idiot grin I get from shooting a large bore rifle.

Since photos of the BA50 other than stock shots from dealers / manufacturer are completely lacking, hopefully these will help people in the future who find themselves in my position researching big ass rifles online! It'll probably take a few posts in a row to get them all added due to the 5 photo limit (I don't want to link them from Photobucket or similar because the links will get broken over time as I rearrange albums).


The rifle itself (with fore-end rail removed) with a snap cap I was using to test extraction and bolt motion
Attached File


Rifle (with fore-end rail left on) sitting in the back of my kayak hauler pickup
Attached File


Interior of the case the rifle ships in, the foam has to be customized / replaced to leave a scope on the upper when stored
Attached File


Upper / lower separated
Attached File


Trigger group, seems to be standard AR15 except for the hammer is a heavier profile and the pins have circlips on the passenger side of the lower to keep them in. Might replace these with anti-walk pins if it becomes an issue.
Attached File

Driver side of the upper with the left-side bolt
Attached File


Bipod, held on by a 3/4" nut. There's about 1/4" free range of motion side to side on the bipod which allows it to shift for uneven surfaces but I don't like how it flops around. I'm going to replace this with an Atlas bipod as soon as I can fabricate an adapter of some sort.
Attached File


Acme threaded muzzle brake, which is not shown in most of the online stock photos I looked at (they show a large rectangular block of a brake). This is the brake for an AAC Cyclops suppressor which I'll probably pick up down the road depending on where the HPA goes.
Attached File


Passenger side of upper showing the bolt closed
Attached File


Same, with bolt halfway back
Attached File

Underside of the upper with bolt closed
Attached File


Same, with bolt halfway back
Attached File


Here's a size comparison to a regular AR15. I believe I used an 18" barrel with carbine stock for the photo, but after looking at it the rifle may one of my 16" barrel ARs...
Attached File


One of the included mags, photo included just because it gave me the precursor of an idiot grin when I picked up the huge magazine
Attached File


Driver side engraving, just because. The anodizing / finish on all the parts is pretty nice and is consistent. No idea how durable it is, but I haven't seen any complaints about it.
Attached File

Very nice setup.  Depending on how much elevation adjustment in your scope you may need one of these for longer distances.

Badger Ordnance Extended Picatinny-Style 22 MOA Elevated Riser Mount 5-3/8" AR-15 Flat-Top Matte
Badger Ordnance

I forgot to mention that, but I used a Nightforce Unimount to mount the scope. It's a 20moa base and the scope itself has something like 100moa vertical adjustment.

I have a Viper Vortex scope with 65 MOA internal adjustment, I needed more and got the badger.

Do you have to remove the allen head screw shown in your last picture to remove the bolt? Any special maintenance or disassembly process for the bolt?

I think you're referring to the screw behind the bolt with the roller bearing on it? I haven't done it myself yet but I don't believe that has to be removed for disassembly (there's a channel in the upper for it). There is an allen screw that's probably hidden by the receiver in the photos (above the bolt handle) that needs to be loosened to release / remove the bolt handle. Once the handle is removed then the whole thing can pull out for cleaning. Lubrication / cleaning doesn't seem any different than a normal AR bolt, but there's a few less parts than a regular BCG.

I have had a ball with mine!!!! The bolt comes out very easily for cleaning. I've stretched mine out to 500 yards with m33 ball and I am totally satisfied with my BA50!!

Thanks for the clarification!

I have shot one (it was a Cobb Manufacturing, purchased before bushmaster bought them out) and with my untrained sniper abilities, I shot three rounds into about 1" at 280 yards.  It might have been luck but it is much more accurate than I am.  He has a Nightforce NSX scope on it if I remember correctly.

Very cool.

I have a COBB that just got back from a Bushmaster Custom Shop overhaul.

Mine is the 22'' carbine version.

I love it.