Mag fed .50 upper


50 Shooter
May 29, 2003, 10:33 PM
To cool to pass up.

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May 30, 2003, 12:36 PM
VERY cool.

/me want

50 Shooter
June 25, 2003, 10:09 AM
They have named it, it's now called the UltraMag 50. They are also taking orders for it now, $1,750.

June 25, 2003, 10:16 AM
The upper weighs ten pounds. :scrutiny:

That had better be one effective muzzle brake. :uhoh:

Black Dragon
June 25, 2003, 12:35 PM
The lower looks like a modified AR lower. Any more information on groups and what not??

Dave R
June 25, 2003, 02:28 PM
How much velocity would a .50 lose in a barrel that short?

June 25, 2003, 03:29 PM
Tamara: Rather, it comes with a super slip 'n slide on which you fire it from. The recoil is transferred into rearward acceleration.

The rifle comes with 50ft of slip 'n slide.

June 25, 2003, 03:37 PM
How much velocity would a .50 lose in a barrel that short? According to Elmer Keith, the WWII era 48" bbl .50 MG would completely burn the powder. The 36" version would leave literally pounds of unburned powder in front of the gun after a firing session. That doesn't answer your question directly but does indicate that the longer bbl is necessary for complete combustion.

June 26, 2003, 06:59 AM
Are there 'pounds' of powder in a 50BMG?

June 26, 2003, 07:00 AM
There are in three or four ammo cans worth of ammunition.

June 27, 2003, 12:16 AM
Hello all - the recoil on the UltraMag 50 is not bad at all. The muzzle brake works great to lower recoil. The prototype has a 16.5 inch barrel but the production gun will have a 22". Than when things settle down we will offer even longer barrels. The lower on the prototype is a DPMS California lower. The UltraMag 50 will work with all AR/M16 lowers. Thanks for the kind words.
Walter Keller
Safety Harbor Firearms Inc.

June 27, 2003, 09:58 AM
man, i had an idea like that years ago, cept it was for 308 or 7.62x39. same mag idea (in the side of the receiver)

gave it up because i figured an M14 (and especially an AK47) mag sticking out of the side of an AR15 would through the entire thing off balance and make it hard to hold level :)

50 Shooter
June 27, 2003, 06:46 PM
The barrel on my .50 is 31" long and using 215grs of powder in the stuff that I reload, there's never pounds of ammo left. In fact I would be suprised if you could find enough unburnt powder after I'm done to load half a .50 BMG case.

Using 215grs of powder I get about 240 rounds loaded from an 8lb jug.

June 27, 2003, 06:49 PM
I think he meant after firing many hundreds of rounds through the MG. Easy to do when uncle sam is footing the ammo :D

July 12, 2003, 04:41 PM
Just added some video of the UltraMag 50 firing.

July 12, 2003, 08:09 PM
The recoil seems to be suprisingly managable.

July 12, 2003, 09:48 PM
The UltraMag 50 prototype has a 16.5 inch barrel and the whole rifle weighs in at around 15 lbs. Being so light you would think it would really knock you around but it does not. Since the barrel is shorter the burning powder does not have time to finish burning in the barrel thus it doesnt create as much recoil . It also helps having a very good muzzle brake too. Even with the shorter barrel at 200 yards we have shot 1 1/2" groups.

July 22, 2003, 08:38 AM
Just added a newer video clip - 3 shot

July 23, 2003, 02:42 PM
Wow, that looks surprisingly controllable. Cool product.

4v50 Gary
July 23, 2003, 02:56 PM
Make it a 36" Walther BBL & I might just get one. Dunno when I may have to stop a calvary charge. ;)

July 23, 2003, 03:30 PM
Just curious, how do the barrel and receiver meet? Through a threaded interface or held together by a weld? Say a barrel is burned out one day, is it a relatively easy task to turn a new barrel and install it or is it a bit more involved? Not just in the event that a barrel should be worn out but in the event that a change in barrel length is desired, such as the introductory barrel one day being replaced by a longer length barrel.

I ask because that's one of the main concerns of mine when debating whether I should go for one of these AR15 uppers or spend another 800-1k dollars and just go right for an AR50 which may prove to be more easy to work with at some point down the road if a rebuild or maintenence is needed.

Is it a freefloated design? And I'm curious how the bolt and receiver lugs interface, steel on steel similar to that of a Reminton 700 or other push feed two lug bolt? Any close up pictures of the action or showing detail of various parts of the action?

That thing has got me pretty darned interested, nicest looking of all the AR15 uppers I have seen for 50BMG.

July 23, 2003, 08:23 PM
The UltraMag's barrel is screwed in making barrel replacement relatively easy.
The barrel is not free floating though - the handguard is held in place by threads midway down the barrel. This feature makes it easier to increase the barrel length and at the same time lengthen the handguard. We will be offering a longer barrel later as thing settle in.
The bolt is a two lug design - like to post some pics but my wife is out of town with the digital camera :-(

July 23, 2003, 08:47 PM
Look what I found - Pics of the UltraMag 50 when it first made its debut. ENJOY

July 24, 2003, 12:03 PM
Those 2-1/2" groups @ 200 yards... Is there a large ammount of match components for the 50BMG? HPBT match grade bullets?

How much do those go for anyway? I'm looking at reloading, and my buddy gets a boxes of (i think) 50 7.62 HPBT for like ~$20. How much do 50BMG bullets go for?

July 25, 2003, 12:25 AM
I'm leaning towards the Serbu BFG 50 altough that slot cut on the right side for the bolt to slide back might just make hash out of this southpaw's cheek.

Or the AMAC

Both can be found and priced at

July 25, 2003, 12:39 AM
Having test fired 300 plus BFG's and being left handed - I have never had any problems with that bolt handle slot cutting my face. I have to admit that same thought has crossed my mind though.

July 25, 2003, 01:11 AM
Looks real nice.

My only thought is that maybe the bolt and the magazine should be switched around. Since most .50BMG shooting is done from the bench, I'm thinking a left handed bolt would be easier to operate while sitting at the bench. Plus the right feeding magazine wouldn't be in the way of your forward arm.

50 Shooter
July 26, 2003, 03:25 AM

Match bullets for .50's cost anywhere from $1- $3 each, I'm talking just the projo's not loaded ammo. The best bullets are solids and are of the borerider configuration. If your looking to buy loaded match grade stuff, expect to pay anywhere from $3- $6 a round.

The fact that theres surplus .50 BMG out there makes the .50 somewhat affordable to shoot. Most surplus stuff runs about $1.20 each for ball and the fun stuff like APIT costs about $1.50. Now if you want an exotic round like the Mk211 Mod 0 Raufous, expect to pay about $35 each if you can find them. Then theres also the SLAP ammo but if your .50 won't chamber it, all you'll have is an expensive paper weight.

July 27, 2003, 04:28 PM

Question for you/ The bolt on the Mag 50 looks a little long. Is it nessesary for correct operation or could the bolt handle be shortened up or changed ?

Any possibilty of selling a set of plans for personal use in the future ?

Looks like a great setup.

July 28, 2003, 08:33 PM
You need a decent length bolt handle to open and close the action. Not as much for handloads but it really helps when firing Mil Surplus ammo. Some Chamber hard and extract even harder. The UltraMag 50 design has some patents pending so selling plans would be like shooting ourselves in the foot. Not that someone wont proably try to copy it soon after its out there.
Well heres the pic of the bipod mounting rails before heading to be anodized
There will be others to follow. :-)

August 25, 2003, 12:31 PM
More UltraMag 50 parts pics - 240' of Scope Rail Extrusion arrived this morning :-)

Badger Arms
August 25, 2003, 12:42 PM
Thanks to California's hysterical ban rush, I am seriously thinking about adding a 50 to my collection. This one looks just right. I'd like to see a 28" or so barrel on there. Is it just me, or shouldn't the gun ballance a little further forward than the carry handle suggests?

August 25, 2003, 02:33 PM
Depends, my heavy as all get out accurized AR15 weighs in at 15 pounds unloaded and one would think it would balance further forward than it does, but I used a stainless steel lower plus have a 3 way adjustable butt plate. The weight out on the end of the buttstock helps because it's out so far.

With the 50, I bet it could be a close call depending on that skeleton stock's weight, some how I don't think the aluminum bar is saving too terribly much weight over that of a plastic stock. Then there's the bipod, if it folds rearward it probably comes real close to balancing properly when folded.

I too am seriously thinking about a 50BMG, though I really want something like an Armalite AR50 as a complete rifle so incase they one day go on the NFA list I'll have a complete rifle with a paper trail rather than just an upper assembly that needs some other registration headaches likely akin to a registered DIAS or Lightning Link. I'm just pissed cause I am missing out on an AR50 group buy that has the price shipped to my dealer as 2400 dollars compared to around the 2800 dollars a local shop wants. Stupid college course tuition..... Can't get the 50BMG monkey off my back.

September 13, 2003, 09:58 AM
being made - visited two shops working on parts today. Heres the Magwell and Handguard.

Walter Keller
Safety Harbor Firearms Inc

September 18, 2003, 11:17 AM
Some more UltraMag 50 parts - the plans coming together :-)

Walter Keller
Safety Harbor Firearms Inc

50 Shooter
September 18, 2003, 11:19 AM
Looking good Walter, I know a couple people that have one on order. Can't wait to give it a try.:cool:

September 18, 2003, 02:56 PM
This is a .50 BMG upper that fits on an AR15 lower? Any idea how an aluminum lower engineered for 5.56/.223 will stand up to .50 BMG recoil? I mean, when you touch off a .50, the lower's going to get whacked pretty hard before the bullet even leaves the muzzle so the brake can do its work . . . it probably won't suffer catastrophic failure, but I wonder how many rounds it will take before something is measurably stretched or distorted?

AJ Dual
September 18, 2003, 04:12 PM
I'm no engineer but I bet it woult take a lot of .50 BMG to adversely affect any quality AR lower.

All of the firing stress/pressure is in the barrel and on the bolt in the upper, and recoil thrust ought to be straight back into the buttstock. The AR lower is only really just a convenient attachment point for the trigger, grip, and the hammer, and isn't really getting any more abuse than your shoulder is.

I would guess as long as the upper mates tightly to the lower it will do fine, since there would be no gap for the upper to pick up velocity and "slap" the lower.

September 18, 2003, 07:33 PM
The UltraMag 50 prototype has 400 plus rounds through it with no real ill effects. Like stated before you want to have a tight fit between lower and upper. Use of a Accuwedge to tighten things up if loose would be a good idea.
Walter Keller
Safety Harbor Firearms Inc.

September 18, 2003, 09:02 PM
If I wind up going the route of a 50BMG upper, I have every intent of getting one of those super ugly DPMS single shot lower receivers.

I'm not about to risk it on a Ca. registered AR15, just WAY too precious and irreplaceable.

Could build up a decent single shot lower for less than 250 I bet, I do have some parts left over from other builds a few years back though.

September 19, 2003, 08:49 AM
The UltraMag 50 prototype has 400 plus rounds through it with no real ill effects. Is "no real ill effects" something like being a little bit pregnant?

50 Shooter
September 20, 2003, 11:13 AM
One of the guys over on Biggerhammer has over 1000 rounds through his .50 BMG upper/AR lower and hasn't seen any type of wear to his lower.

September 28, 2003, 09:32 AM
Well its getting close - More parts arriving every day.
There more pics in the gunsnet site.
Those of you attending the Knob Creek MG shoot stop by table B-19 in the pole barn we should have the first production uppers there on display.
Walter Keller
Safety Harbor Firearms Inc

October 27, 2003, 11:24 PM
We are close to start shipping the first uppers - waiting on the
magazine springs.
Walter Keller
Safety Harbor Firearms Inc.

October 28, 2003, 02:01 PM
One with a 29 inch barrel, that's more like it :)

Hmmmm, now you're really starting to ignite my passion for things that go boom.

How much for one with a 29 inch barrel?

October 28, 2003, 07:44 PM
When is someone going to come out with a semi auto .50 bmg handgun with like a 5 inch barrel. If I ever bought a .50 bmg It would have to come with a 16 inch barrel because of weight and I'd just want to blow stuff away with it.

Black Snowman
October 28, 2003, 08:07 PM
I don't think it's possible to make a semi-auto .50 BMG action short enough to qualify as a pistol. I've seen a bolt action 50 BMG pistol which they were barely able to make short enough to qualify as a pistol.

Look at the action length of a Barret Mod 82. Very difficult to get that down to pistol size. Plus with a 5" barrel you're looking at a flamethrower, not a gun. You'd have next to no velocity with a 50 BMG. You'd get a lot more muzzle energy from something like a .500 S&W revolver or single shot pistol using a rifle cartridge. Not to mention some accuracy.

The demand is nil and physics are against you my friend ;)

October 28, 2003, 10:13 PM
$2000.00 for the 29" upper. Speaking of 16" barrels the prototype UltraMag 50 has a 16.5 barrel. With that barrel its a fun gun to shoot - the ultimate plinker :-) We will proably do some 16.5 barrels once things settle down.

October 29, 2003, 01:45 AM
Oh Please don't talk a bunch about making one. What people have seen that look like one are really registered Short Barrelled Rifles. AOW's. If someone SHOULD actually build a commercial 50 BMG pistol, we would automatically have ALL Military Surplus ammo banned because it all has steel core and would be classified as Armor Piercing.

As Black Snowman said, the short barrel would be absolutely useless in a BMG. Even the 18 inchers suffer several hundred fps loss vs. the longer tubes. Most folks use around 31 as the best compromise between velocity and weight. Rob

October 29, 2003, 03:25 AM
How will it be banned? Because .50bmg would be handgun ammo? They make a m-16 pistol and You can get steel core ammo I think.

October 29, 2003, 03:42 PM
You cannot get true "steel core" ammo for the 5.56x45mm.

M855 and loads using the SS109 "steel penetrator" bullet are a special case that the BATF has ruled to not be an AP round. The AP laws/regulations are setup specifically to deal with rounds for which handguns are readily available, for these cartridges which handguns are made the considerations are: special bullet design such as truncated cones coming to a sharp point, hardened metal cores comprising a certain percentage or making up that of the entire bullet, special coatings, or any one of a combination of those things.

Yes, there are 5.56x45mm handguns out there such as AR15 pistols, but the SS109 bullet is largely comprised of a lead core, the steel in the SS109 round doesn't really do diddly. True AP like the M995 round which has a tungsten core, now that would be a no-no.

December 13, 2003, 07:12 PM
Been awhile since I've posted but we are shipping uppers - 14 so far. Hoping to get more out before the holidays.

Walter Keller
Safety Harbor Firearms Inc.

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