Velocity VMAC-45 jamming with hollow points

[gameragodzilla]

Finally took my VMAC-45 to the range to shoot after having my gunsmith weld on some aftermarket rails, but the gun has a failure to feed with hollow points multiple times this range session. The gunsmith also said that he encountered the same thing when he test fired it, but he didn’t know how to get hollow points running and so didn’t want to risk anything. All the stuff he did worked fine, the brace, the red dot and the light, but I need this gun to run reliably with Winchester Ranger T since I want to make this a bag gun. My 1911 carry load is that hollow point and I want to run the same ammo in my VMAC but it doesn’t seem to work. Also tried some cheap Remington hollow points (the stuff I shot today with pics) and they also jammed. My gunsmith did also fit in an aftermarket paddle magazine release when he fired my gun, but I put in the original magazine release and still had the same issue. There also didn’t seem to be any specific magazine that worked better than the other. Both him and I only had 2 magazines function flawlessly out of the 5 we fired, but the specific 2 magazines were different between us. The ones he fired flawlessly malfunctioned for me. Both of us also experienced one stovepipe too.

So can anyone tell me how best to get this gun working with hollow points? Or point me to a MAC-10 specialist who can get it running? This is the only thing left for me to be fully satisfied with this gun.

Thanks.

 

[strobro32]

HP is a known problem with M10 style guns. Some will say they get them working but 98% will have a problem.

 

[gameragodzilla]

HP is a known problem with M10 style guns. Some will say they get them working but 98% will have a problem.

Any gunsmith capable of getting them working? I'm willing to pay that extra money for that since I would like to make this a bag gun and this is the only pistol grip magazine PCC in .45ACP as far as I'm aware.

 

[gameragodzilla]

Bag gun? What's a "bag gun?"

A smaller gun that fits inside a small bag for when I'm going to a hotel or something that has greater capacity and effective range than my pistol but is still smaller and easier to carry than my AR-15 or shotgun (so I won't be bringing those with me outside my home).

That's why I want it specifically to shoot hollow points, since I do want to use it as a defensive gun and it's the only one in .45ACP. Accuracy at the range was great, the mounts all worked great for the folding brace, red dot, and flashlight. The M3 Grease Gun mags all locked in just fine. So the only thing left to make this satisfactory is making it run hollow points, or at least just my carry load.

 

[SecondAmend]

... this is the only pistol grip magazine PCC in .45ACP as far as I'm aware.

Uzi in .45 ACP

 

[gameragodzilla]

Uzi in .45 ACP

I have heard of those, but nobody makes one OEM as far as I'm aware. So MAC-10 clone it is, especially since the Velocity Arms VMAC-45 was pretty cheap as well, which left me more money for all the extra accessories. Now I just want this gun to work with Winchester Ranger T hollow points and I'll be perfectly happy.

 

[Slowmo]

What mags are you using?

Also, maybe try another good load like HST or Gold Dots.

 

[gameragodzilla]

What mags are you using?

Also, maybe try another good load like HST or Gold Dots.

I have one OEM magazine from Velocity that had a jam, and then another 10 from KeepShooting. They're all standard M3 Grease Guns. 4 I haven't taken out of the bag yet, but the other 7 have been fired at least once, with no consistency in whether they work or not. The mags that worked fine for the gunsmith malfunctioned when I tried them, while some mags that malfunctioned for the gunsmith worked fine for me. But there was no consistency.

And I have tried two types of hollow points. The Winchester Ranger T which I want to use as my carry ammo and some Remington hollow points I bought for cheap. Both had malfunctions exactly like the feeding I showed in the pictures.

 

[root]

Throat the barrel maybe.
They call the HP 45acp the flying ashtray for a reason.
Home throat job here.

I throated an UZI barrel in the most BS way possible and it works great.

It occurred to me that the chamber end of a mil-spec UZI SMG barrel is kind of crummy for feeding FP rounds. The "funnel" part is too small. I made some very careful measurements and it turns out that you can open the "funnel" at the breech end of the barrel quite a bit without cutting into...

www.uzitalk.com

And you will need to remove the barrel to do it.
There are threads here for that too.

 

[gameragodzilla]

Throat the barrel maybe.
They call the HP 45acp the flying ashtray for a reason.
Home throat job here.

I throated an UZI barrel in the most BS way possible and it works great.

It occurred to me that the chamber end of a mil-spec UZI SMG barrel is kind of crummy for feeding FP rounds. The "funnel" part is too small. I made some very careful measurements and it turns out that you can open the "funnel" at the breech end of the barrel quite a bit without cutting into...

www.uzitalk.com

And you will need to remove the barrel to do it.
There are threads here for that too.

Hmm, I'm not competent enough to do that myself, especially since it looks like the barrel is welded into the upper receiver? But has anyone else done this with enough success that they can give detailed instructions so my gunsmith can replicate it? Or maybe having another MAC specialist gunsmith do it?

It did look like the throat of the barrel was a bit tight since if I slow load a snap cap, it gets hung up as well. Though the angle is random since it seems to jump out of the feed lips when that occurs rather than the consistent upward tilt when firing, but would all of that also be fixed if the throat is widened for more room to feed?

 

[Slowmo]

I have one OEM magazine from Velocity that had a jam, and then another 10 from KeepShooting. They're all standard M3 Grease Guns. 4 I haven't taken out of the bag yet, but the other 7 have been fired at least once, with no consistency in whether they work or not. The mags that worked fine for the gunsmith malfunctioned when I tried them, while some mags that malfunctioned for the gunsmith worked fine for me. But there was no consistency.

And I have tried two types of hollow points. The Winchester Ranger T which I want to use as my carry ammo and some Remington hollow points I bought for cheap. Both had malfunctions exactly like the feeding I showed in the pictures.

KeepShooting mags are good mags, but they are not the same as GI mags. You could seek out some surplus GI mags to try.

Also, I know you mentioned that you tried two different hollowpoints and neither of them worked. That’s why I am recommending trying something different. Doing the same thing over again isn’t likely to solve the problem.

Trouble shooting sucks and is expensive. I’m dealing with it right now on another gun.

 

[gameragodzilla]

KeepShooting mags are good mags, but they are not the same as GI mags. You could seek out some surplus GI mags to try.

Also, I know you mentioned that you tried two different hollowpoints and neither of them worked. That’s why I am recommending trying something different. Doing the same thing over again isn’t likely to solve the problem.

Trouble shooting sucks and is expensive. I’m dealing with it right now on another gun.

Yeah, though I mentioned the two hollow points as why I think switching ammo is unlikely to work. Especially since the Remington and Winchester Ranger T hollow points seemed to have very different bullet profiles. So seems like having a different bullet shape isn’t working.

Guess I’ll try GI mags, though I wonder if KeepShooting makes the OEM mags for Velocity. I couldn’t see any difference between those mags. If the OEM mag is an actual GI mag as well, then that one malfunctioned too.

And yeah, it does. I’ve had to deal with it for a few guns, though I always resolved the problem and made them reliable eventually. Also why I was happy to purchase a Velocity VMAC-45 since those were around $550 OEM rather than some of the used, out of production stuff going for thousands. That left me with more money to throw around for troubleshooting but all the money in the world can’t help if I can’t find the right person to fix my gun.

 

[root]

For my M10 I prefer the keep shoooting mags. I do have some USGI mags but fit are hit and miss.
I'll buy a dozen off a member get two or 3 that fit and pass the rest along.

Never tried hollow points in the OEM 45 upper but 9mm hollow points work in my Lage 10/31 upper out of suomi drums not that that matters.

 

[gameragodzilla]

For my M10 I prefer the keep shoooting mags. I do have some USGI mags but fit are hit and miss.
I'll buy a dozen off a member get two or 3 that fit and pass the rest along.

Never tried hollow points in the OEM 45 upper but 9mm hollow points work in my Lage 10/31 upper out of suomi drums not that that matters.

Yeah, I would prefer using the KeepShooting mags given they’re new production and I can bulk buy them for relatively cheap ($30 a pop). But the hollow points not working in any of those mags reliably sucks.

I wonder if there are any other uppers compatible with a semi auto closed bolt VMAC-45 lower that would feed more reliably. I’d prefer getting this upper working, but if necessary, I can switch.

 

[Slowmo]

Yeah, I would prefer using the KeepShooting mags given they’re new production and I can bulk buy them for relatively cheap ($30 a pop). But the hollow points not working in any of those mags reliably sucks.

I wonder if there are any other uppers compatible with a semi auto closed bolt VMAC-45 lower that would feed more reliably. I’d prefer getting this upper working, but if necessary, I can switch.

Depending on where you live, you might be able to find an Uzitalk member who would let you try out a USGI mag. A vendor named leetool sells them on this and other sites. Until recently the price was $400 for 10 in wrapper, shipped. I think he just went to $450 for 10. I’ve bought two batches from him and been happy with them. You can also find USGI mags on Gunbroker for around $40 or so, but shipping usually runs up the price.

I don’t know with certainty whether USGI mags will fit a Vmac. The original Mac .45 mags were just slightly modified USGI M3 mags. Most Macs will work with unmodified mags with a dual-cut magazine catch or by slightly modifying the original mag catch with a file. I don’t know if the Vmacs will or will not work with the unmodified mags but it is a simple part/modification to test. If I’m not mistaken, the KeepShooting mags are made to run in unmodified guns, so they differ slightly from USGI mags.

 

[gameragodzilla]

Depending on where you live, you might be able to find an Uzitalk member who would let you try out a USGI mag. A vendor named leetool sells them on this and other sites. Until recently the price was $400 for 10 in wrapper, shipped. I think he just went to $450 for 10. I’ve bought two batches from him and been happy with them. You can also find USGI mags on Gunbroker for around $40 or so, but shipping usually runs up the price.

I don’t know with certainty whether USGI mags will fit a Vmac. The original Mac .45 mags were just slightly modified USGI M3 mags. Most Macs will work with unmodified mags with a dual-cut magazine catch or by slightly modifying the original mag catch with a file. I don’t know if the Vmacs will or will not work with the unmodified mags but it is a simple part/modification to test. If I’m not mistaken, the KeepShooting mags are made to run in unmodified guns, so they differ slightly from USGI mags.

The VMAC45 was designed from the get go to take standard Grease Gun mags, so it should be good to go without modification. The paddle mag release I bought from Practical Solutions was also for unmodified Grease Gun mags.

How do the KeepShooting mags and true USGI mags differ? Don’t want to spend money buying a very expensive USGI mag only for it not to work.

 

[Slowmo]

The VMAC45 was designed from the get go to take standard Grease Gun mags, so it should be good to go without modification. The paddle mag release I bought from Practical Solutions was also for unmodified Grease Gun mags.

How do the KeepShooting mags and true USGI mags differ? Don’t want to spend money buying a very expensive USGI mag only for it not to work.

Have you tried the magazine catch that came with the gun? Magazine height can affect the type of jams you are having. A magazine release cut for unmodified mags will make modified mags sit lower, possibly too low.

I’m fairly certain the rear plate of the Keep Shooting mags is cut the same as a modified mag. If that is correct, an unmodified USGI magazine will sit higher.

Do your Keep Shooting mags have much vertical play when locked in?

 

[gameragodzilla]

Have you tried the magazine catch that came with the gun? Magazine height can affect the type of jams you are having. A magazine release cut for unmodified mags will make modified mags sit lower, possibly too low.

I’m fairly certain the rear plate of the Keep Shooting mags is cut the same as a modified mag. If that is correct, an unmodified USGI magazine will sit higher.

Do your Keep Shooting mags have much vertical play when locked in?

Tried both. Gunsmith fired with the paddle release, I put in the OEM mag release and had the same problem. Though if the rear cut is the same as a modified mag, then both mag catches would be an issue. However I thought it was a standard Grease Gun mag.

Didn’t notice any vertical play though. In fact, the reason I wanted the paddle release in the first place was because the standard mag release was extremely difficult to open with a full mag on a closed bolt (since my VMAC is a closed bolt clone).

 

[Slowmo]

Tried both. Gunsmith fired with the paddle release, I put in the OEM mag release and had the same problem. Though if the rear cut is the same as a modified mag, then both mag catches would be an issue. However I thought it was a standard Grease Gun mag.

Didn’t notice any vertical play though. In fact, the reason I wanted the paddle release in the first place was because the standard mag release was extremely difficult to open with a full mag on a closed bolt (since my VMAC is a closed bolt clone).

My recommendation is to take the upper receiver off and remove the bolt assembly, then lock in the various magazines you have available to you and see if there is any vertical play. If there is no substantial vertical play, I don't think a USGI magazine or swapping magazine catches will help. If I remember correctly, the difference is about 1/8". If there is vertical play, that means that the magazine is not sitting as high as it could, and raising the magazine or using a magazine that sits higher may help reliability.

Going back to ammo, you could also try Hornady XTP ammo since it is shaped quite differently from the typical .45 HP.

Otherwise, I'm not sure I have anymore ideas for you.

 

[gameragodzilla]

My recommendation is to take the upper receiver off and remove the bolt assembly, then lock in the various magazines you have available to you and see if there is any vertical play. If there is no substantial vertical play, I don't think a USGI magazine or swapping magazine catches will help. If I remember correctly, the difference is about 1/8". If there is vertical play, that means that the magazine is not sitting as high as it could, and raising the magazine or using a magazine that sits higher may help reliability. Going back to ammo, you could also try Hornady XTP ammo since it is shaped quite differently from the typical .45 HP. Otherwise, I'm not sure I have anymore ideas for you.

Just tested that while on the phone with Practical Solutions and the mag doesn’t have much vertical play. They said maybe hang time could be an issue due to hollow points being shorter or maybe the feed ramp angle is too high for this round? Not sure. I’m totally new to the Mac platform so even the basics are beyond me.