Super Fast, super light .50 cal bullet?

[Nando Aqui]

A co-worker was taking about his adventures with his Barrett .50 cal rifle. I arrived when the conversation already was underway, but gathered these bits: he uses 186-gr bullets, and has chronographed them at over 5,000 fps. Since I did not know what had been said before I arrived, I did not question what I heard.

Two days later, I made the point of asking that individual about what I thought I had heard him say, and he asserted that I had heard correctly. He then reiterated that for his Barrett .50 cal, he uses 186-gr bullets, and that the fastest speed he has been able to attain was chronographed at 5,071 fps. Obviously, a lot of smart remarks came to mind, such as 'are you using wooden bullets with afterburner inserts?", but I kept my mouth shut, and just said, "Wow!"

The lightest bullets I can find listed for a .50 BMG are all well over 600 grains, and the fastest speed I can recall for any rifle cartridge, if memory serves my right, was the .220 Swift at just over 4,000 fps.

But, I have learned never to say that anything is impossible, so I ask you:

Is this man’s “.50 cal, 186-gr bullet, 5000 fps” recipe even possible, or is he delusional?

Thank you for you opinions.

 

[TexasRifleman]

Short of a sabot round I cant imagine getting a .50 cal bullet to weigh that little. Maybe it's made of aluminum?

Gotta call BS on that one.

I suppose you could fire a sabot round in a Barrett so there's a slight chance that's what he is talking about I guess.

 

[Sunray]

He might be getting that speed, but I'd bet it doesn't feed. It'd be like shooting a WC. Voids his warrantee too. I suspect he's, um, stretching the truth.

 

[taliv]

like texas said, sabot rounds are popular* in 50bmg. they let you fire any 30 cal projectile from your 50bmg. you can order them from eabco.com. claims of 4500 fps are not uncommon with the 30cal sabots that let you shoot 224 caliber projectiles from a 308win or '06, etc.




*on paper. i don't know anyone who has placed a 2nd order

 

[kir_kenix]

i talked to an armorer the other day who told me that there was once a military program that was testing saboted .50 bmg rounds. i have no idea if it was true or not, but he said they were using 220 grain .30 or .33 cal projectiles at 4800. i thought it was total bs until i read taliv's message. maybe your friend came across this on the net or knows somebody who is familiar with the program and just parroted their findings. or else, maybe u should go to the range with him and shoot his barrett for yourself .

 

[S&WKING]

actually the fastes rifle is the 204 at 4225 fps but im sure someone could load them faster than that

 

[taliv]

btw, i could never get a decent chrono reading because the sabot would separate from the bullet but both would go through the chrono at almost the same time. so i have no idea how fast my .224 55g fmgs were going out of my 308win. but the load data they print on the package is impressive. i haven't actually ordered any of the 50 cal sabots.

i also don't know anyone foolish or cool enough to put a .224 projectile in a 30 cal sabot, then put that assembly into a 50 cal sabot and load it in a 50bmg, but 230g of powder behind a 55g projectile would be interesting.

 

[gpdave]

Well, the military tested SLAP (Saboted Light Armor Penetrating) rounds. . . something like a 300-ish grain bullet at around 4000-ish fps.

If you reduced the bullet weight to 186. . . maybe you could get up around 5000. . . I dunno.

 

[Jim Watson]

The military .50 SLAP was doing about 4000 fps but that was with a heavy tungsten AP. No doubt you could go faster with a conventional bullet in .50 sabot. So the guy's story is not totally bogus. I know of no standard 186 grain bullet you could put in a sabot, though.

Maybe he has some sort of light metal .50 bullet. The CETME design with an aluminum core in a copper jacket might do.

Note that he says nothing about HITTING anything. I know the Remington Accelerator .22 in a .30-06 sabot round was fast but not very accurate; not in my guns.


Ask him to SHOW you a round or bullet.

 

[taliv]

jim, that was my experience too. if you search the reloading threads a few years back, you'll probably find some posts where i was whining about accuracy (lack thereof) with the sabots.

btw, the 204r might be one of the fastest large production rifles, but there are certainly faster cartridges

 

[eliphalet]

Usta have a article in an American Rifleman about the military using 30 caliber armor piercing sabot's in 50's. I do remember the penetration at the distances and angles stated were quite impressive, but it has been to long ago to recall the exact numbers.

 

[jpwilly]

Well as far as I know most 50 cal muzzle loaders use sabboted bullets maybe hes shooting some of those?

 

[50 Shooter]

The M903 SLAP round will do 4000 FPS out of a 45" M2 barrel, the M82 has a 29" barrel. While it might be possible to push the round to 5000 FPS I highly doubt it's accurate. The aftermarket sabot petals that are out there for use with .30 cal bullets aren't that great. The best accuracy that I've heard of is minute of barn.

The biggest problem with the aftermarket sabots is trying to perfectly center the .30 cal bullet in the sabot. Plus you need to remove the muzzle brake on the rifle to keep the sabot from contacting it when it leaves the barrel. Failure to due this could lead to your brake being blown off and causing injury to the shooter or bystanders.

Here's a good link to .50 BMG ammo. http://www.inetres.com/gp/military/infantry/mg/50_ammo.html

 

[benEzra]

What are the lightest available bullets for the .50AE pistol caliber? Could you load one of those in a .50BMG case? The ballistic coefficient would absolutely suck, but the muzzle velocity might be impressive.

I suspect he's probably using sabots.

(But, how much would a short, turned aluminum bullet in .50 caliber weigh?)

 

[taliv]

can you shoot a .500 projectile in a barrel intended for .510 ? seems kind of a big difference. 50ae is .500 right?

 

[dakotasin]

i'm not 100% positive, but i believe it is about impossible to get over 5000 f/s w/ standard cartridge designs (like the 50 bmg) because the rate of gas expansion (burning powder) is about 5000 f/s... could be wrong - i never cared enough to research it fully.

 

[elmerfudd]

Since a .50 BMG typically has a 1-15 twist rate and the ideal twist rate for a .30 186 grain bullet is closer to 1-11, I'm kind of skeptical about the accuracy that such a combination would deliver. Maybe a larger diameter 186 grain bullet would be better stabilized, but then again the BC would suffer and it seems to me that the only reason for such a rifle would be long range shooting.

Still it's an interesting idea. I'm surprised that there don't seem to be many people wildcatting with the .50 BMG case. I'd think that a .375 bullet being fired from a necked down .50 would have some awesome ballistics.

 

[Wes Janson]

I think it can be safely assumed that even if it is possible, you're not going to have anything vaguely describable as accuracy. I've never heard anything about accurate shooting with .50 sabots, period. That said, while I've never heard of anyone shooting sub-200gr projectiles at 5k, that's not to say that it's not possible. But it would definitely be pushing the experimental envelope.

Perhaps your friend was simply messing around with some of the .50-to-.30 sabots, and got an erroneously high reading once or twice from the chrono. That seems most likely to be the case, IMO.

 

[wayne in boca]

The SLAP rounds can't be fired through a barrel with a muzzle brake without catastrophic consequences.Sabots tend to open while in the brake and the situation deteriorates quickly.

 

[IndianaBoy]

actually the fastes rifle is the 204 at 4225 fps but im sure someone could load them faster than that

Do you mean with factory ammo?

I haven't heard anything from handloaders able to squeeze much more than 4k from their 204s. Hard to duplicate the powder blends that Hornady is using to get that kind of speed anyway. Anyway, there are factory loads for the 220 Swift and 223 WSSM that outspeed the 204, albeit with higher powder charges.

If you are talking about handloads, you are way off the mark. MV well in excess of 4500 fps are available with load data from accuratereloading.com for the 220 Swift and the 22-243 Middlestead. I have a Swift, but I have no intention of ever 'hotrodding' it. There just isn't much point. Even so, 4k is easily obtainable with 50 grain bullets in the Swift.


As for the fella shooting the BMG, he might be shooting saboted rounds, but he is likely FOS.

 

[jmorris]

http://www.maadigriffin.com/ sells the sabots and used to have load data posted as well, I do remember velocities in excess of the 5000fps mark.

 

[Jim Watson]

We are speculating in the absence of evidence.
Maybe Nando can get a ridealong for his next outing, eh?
Or not, which will tell a lot about his claims.

 

[taliv]

We are speculating in the absence of evidence.

yeah, but it's a lot more entertaining than the work i'm supposed to be doing

 

[Geno]

One major problem is burn-rate. That's pretty high velocity for powder. I know that technically it is possible. There have been similar posts within the past year. But, that's really pushing in terms of burn-rate.

 

[SaMx]

Ask him if he's using a sabot or an actual .50 round. If he says he's using a .50 round, then he's full of it. Even the .50 pistol bullets weight at least a couple hundred grains.