AR15 in 45 ACP

[Afalex1]

Since I shot TLM's Just Right Carbine in 45 ACP and I have a 45 Octane on the way I have had the itch for a .45 ACP carbine. I stumbled upon Macon Armory on another forum. He is currently a small shop and is specializing in pistol caliber direct impingement uppers.

I put in a special order for an 8" .45 ACP upper threaded 5/8-24 with a HK USC magazine adapter that will allow me to use USC mags in my standard AR15 SBR lower. Rudy is currently using Promag USC mags and says he has put 450 rounds through the two he has and has not had an issue with reliability.

There is about a 30 day lead time on the upper since it is all custom built. Rudy at Macon Armory is very easy to talk to and is very willing to help/explain things. I am excited to get this upper and put it to the test on some hogs at really close range.

When it comes in I will post some pictures of it and maybe a short video of shooting it. Hopefully I will be posting some video/pictures of dead pigs with it too. I'm interested to see what a 230 grain round nose flat point does to a hog at 20-30 yards. I'm guessing it will kill them, but will not knock them down like a rifle by any means.

More to come once I get things in my hands.

Email Rudy at rudyk@maconarmory.com if you are interested. His website is currently under construction.

 

[rob072770]

Alex what ammo are you,planning to use factory or load your own?

 

[Afalex1]

I plan to load my own. I'm going to start with plan old winchester white box, just to function test and play. My hand loads will consist of unique powder and 230 grain lead round nose flat point bullets. They have a hardness of 18 bhn.

Rudy at Macon Armory emailed me today and said my upper function tested great, but he had to go with a 10.5" barrel in order for it to clear the handguard and function reliably with the USC mag adapter. However, if I were to use a dedicated AR45 lower like the one CNC Guns offers he could cut the barrel all the way to 5" and make it work without issue. I'm happy with a 10.5" barrel. It should let me get the maximum velocity from a 45 ACP.

 

[pruhdlr]

IMO ......... a lighter weight bullet at higher velocity will work better for you. Especially one with a good hollow point. The 185gr Hornady XTP comes to mind.

I have killed hogs using the Hornady 230gr XTP +P,however they seem to do more penetrating than expanding. If you want something that will expand more than penetrate,give the 165gr CorBon a try.

A "low speed" solid lead bullet,no matter the nose profile or the hardness,will not do the proper damage to the intended game animal. --- SAWMAN

 

[Afalex1]

I'll have to look at loads with 165-185 grain bullets. I don't want to be above 1000 fps, but still need decent kinetic energy.

 

[Ratdog68]

With the SPS' CC 185gr hp, I'm loading 6.5gr of Clay's Universal.

 

[TEXASLAWMAN]

Use the heaviest bullet you can find. You are shooting subsonic so the lighter faster theory does not apply here.

 

[Afalex1]

That's what I am thinking. Slow and heavy to create the Kinetic energy needed to disrupt tissue and nerves while penetrating.

Shooting subs is more related to shooting an animal with an arrow. Of course, no broadhead to make a mess of things.

 

[pruhdlr]

IMO ...the kenetic energy will me lost and be a moot point if the bullet rather quickly passes thru without having the velocity to both expand AND cause a hydrostatic shock wave.

Even the Hornady XTP line of pistol bullets will somewhat enpand at the slower vels. The hogs that I have hit with the 230gr XTP at >1000fps looks as it they expanded a little judging by the exit hole. Of course if the bullet brings some bone out with it,this could be a false "tell". I do not believe that you could get a 230gr supersonic out of a 16"bbl.

Personally ..... if I did not have a sheet load of the 230's I would switch to the 185's for the velocity --> expansion --> shock value. --- pruhdlr

 

[TEXASLAWMAN]

Your missing the point he is doing it to be quiet he does not want to break 1000 fps. Because of the sound. So once you are at subsonic speeds heavier is always better. I know my 230 gr rangers have no problem expanding on hogs subsonic!

 

[rob072770]

Your missing the point he is doing it to be quiet he does not want to break 1000 fps. Because of the sound. So once you are at subsonic speeds heavier is always better. I know my 230 gr rangers have no problem expanding on hogs subsonic!

+1 I like the 230 HTP just under super sonic and a hard hitting bullet. I like Titegroup it keeps bullet around 800 to 850 feet second.

 

[BigRedDog]

for any pistol caliber AR be very wary of what you use on it for sighting.
Buddy broke a very nice PVS-14 with a couple of shots from a 9mm AR.

Probably should stick to a laser.

should be a lot easier to find pistol bullets that expand at subsonic velocities.

depending on a few variables, your upper limit in speed is around 1050 fps.

first round fired may "pop" but the next few will be quiet

 

[Itsazonik]

The more I see people talking about a .45 rifle the more I think I need one. I was thinking along the lines of a green laser as a sight for it. My buddy has a .45 upper and it rattled a Nikon buckmaster apart in about 30 rounds. I didn't think a pistol caliber round could do that. I keep looking at the glock rifles. I already load some good .45 rounds for my 1911 with the different xtp bullets. Only shot them into wet newspaper but they expand well.

 

[rob072770]

for any pistol caliber AR be very wary of what you use on it for sighting.
Buddy broke a very nice PVS-14 with a couple of shots from a 9mm AR.

Probably should stick to a laser.

should be a lot easier to find pistol bullets that expand at subsonic velocities.

depending on a few variables, your upper limit in speed is around 1050 fps.

first round fired may "pop" but the next few will be quiet

Now that is interesting. Hum might have to,ask Eric if it would stand up. Mine is rated up to 7.72x39. One would think it would But before I shot it would like hear it is OK

 

[Afalex1]

The blowback operated pistol uppers will destroy optics. The gas impingement uppers recoil similar to a 5.56 or less.

 

[Afalex1]

I did a little more research on pvs14s and pistol caliber AR15s. Heres a link to a chart that gives the peak acceleration forces from different calibers.

http://www.ar15.com/archive/topic.html?b=6&f=18&t=368820

I don't like to link other forums here but I feel this is good info. I don't know how valid it is, but I do know it pertains more to ITT pinacle tubes then L3.

I've used my L3 tubes on 7.62x39, 6.8, and 5.56 for two years without issue. These rifles ranged from light weight m4 style ARs, 12.5" 6.8 sbrs, to heavier DMR type rifles. I had a client with a Remington R25 in .243 that used a pvs14/eotech combo without issue.

I find it hard to believe that a gas impingement 45 acp will produce enough shock to hurt a pvs14 when other larger calibers out of a similar weight rifle don't phase it.

Then again, I'm not a physics guy.

 

[TEXASLAWMAN]

Mine has no recoil whatsoever wonder if its because its a blow back instead of direct impingement?

 

[Afalex1]

Direct impingement is supposed to have less recoil then blow back.

That's why I said I don't know the validity of the arfcom Guy's physics math. I guess there is a difference between felt recoil and peak acceleration. Of you read the graphs/charts it shows that a 338 lapua has a higher peak acceleration than a 50 bmg and is why the 338 lapua is an optics killer.

I think the relationship between rifle weight, bullet mass/size, powder charge, and powder burn rate all have to be considered. I think his calculations are all based off of a rifle weight 4 kg (8.8 pounds)

I wonder what Ident Marking thinks about this?

 

[BigRedDog]

Felt recoil is a bit different then the shock that goes to the optic.
To me the 9mm was softer, but to the optic it is deadly.

Don't know why, just know that it happens.

 

[Afalex1]

I'm going to consult with Ident marking about this a little more. In the mean time I will either mount a laser or just look through my EOtech with the PVS 14 on my helmet. I'm still excited about this upper. Hopefully it will be here soon.